There had been heavy storms during the train journey up to Gladstone and we were somewhat concerned about the likely rough crossing next day to Heron Island on the Great Barrier Reef. Once on the boat many of the younger passengers were doing what young people do when setting sail for a holiday island: drinking and having fun. But they soon settled down, when the little boat began to toss in the waves beyond the shelter of the coastal islands. The happy chatter died, giving way to the roar of the battling engine and churning waves, and slowly the smell of vomit began to pervade the sea air. Having experienced some rough water before, we stood most of the way with eyes fixed on the horizon, and arrived little worse for wear, after the five-hour crossing. I learned in the bar that night that there had been bets laid on how long the journey would take: one of the longer guesses won.

 

The inhabitants of the bar were mainly people who worked on the island, but under the bench was one of nature's most experienced salts - it had just arrived from a journey around the Pacific Ocean. It was a mutton bird or shearwater; a bird beautifully designed for flying the oceans, but very clumsy on the land. All night we heard others coming in, many colliding with the side of the chalet, or landing on the roof, others giving eerie calls from their burrows underneath. Next day at breakfast we found Heron Island silvereyes cheekily hopping on the table and stealing sugar, while outside we were advised to wear hats to catch droppings from the thousands of noddy terns nesting in the pisonia trees on the tiny island. All signs of the storm had gone and the coral island was all there, waiting to be discovered - a paradise for escapees from the cold, grey, November of England.

CLAM. Symbiotic relationships abound on coral reefs. The clams have cyanobacteria in their colourful mantles which are photosynthetic and provide food for the clam, while the clam provides a safe environment where the bacteria can obtain carbon dioxide and nitrogen and phosphate.

One of the first fascinations was with clams. We all know about giant clams, but I had never really discovered much about them, rather assuming that they were filter feeders like most other bivalves. Walking through the shallows of the reef one of the first things I found was a clam: not giant, but beautiful. There it was, just wedged firmly in a cleft of the reef. The shell was partly open with its brilliantly coloured mantle flaps spread out in the sun. This one was iridescent blue on a black background. As I walked over the reef, there were others, all had different hues - green, black, orange, yellow, chocolate, each arranged in a unique pattern. I had never really appreciated that these animals were photosynthetic - that they derived most of their food from sunlight. The same applied to the variety of corals, because all these animals contain photosynthetic symbiotic bacteria.

 

Later on we went snorkelling. The boat dropped us into water close to a neighbouring reef. The experience was quite unnerving, because the water was over ten metres deep and so clear that it felt as if we were suspended in air, and could almost fall to the coral garden below. The fish were amazing, busy activity everywhere with all shapes and sizes, patterned in the colours of the rainbow. Someone saw a shark, and I became uneasy when a pilot fish began swimming in front of my mask: where was its shark? Shark attacks are almost unknown there, but knowing that did not make me feel secure when, on another occasion, I came over a deep hollow in the reef, and was too late to stop myself swimming over a pair of two metre long sharks lying on the bottom. They look huge and uncomfortably close under water. The sharks were totally uninterested in me, although their sensory system had already told them everything about me: monitoring my heartbeat, level of fear - panic! Pilot fish are thought to help guide sharks to food, but they probably just make use of bits dropped by sharks when feeding.

 

Other fish really do perform a service, like the cleaner fish, which advertise their presence with a characteristic swimming motion and bright colours. They nip parasites off larger fish and clean their teeth and gills. They sometimes bite too hard and become partly parasitic, like oxpeckers in Africa, which will feed on blood. Coral shrimps have also developed the cleaner habit, ensuring their safety with a fish-chokingly spiny body. In the shallows we saw a large anemone: a clown fish was dashing in and out of its deadly tentacles, unstung because it coats itself with anemone mucus. These fish may return favours by luring prey into the deadly tentacles. Other anemones had damsel fish in them or colourful shrimps. The reef was alive with symbiotic associations.

DAMSELFISH. Many mutual associations develop on the reef, like this damselfish with a stinging anemone. The fish coats itself with mucus off the anemone, so that the stinging cells react to the fish as if it was part of itself. The fish attracts potential prey into the stinging arms and receives protection from predators in return.

Evolution of Altruistic associations

How can these apparently altruistic associations arise in such a self-seeking world? We understand that the main mechanism leading to evolutionary change is the process of natural selection, which acts on variations within a set of entities: anything from physical particles to living things. Within any set, those combinations which last longest or produce most surviving offspring, are more successful than their competitors and so are likely to become more common. This inevitably means that blind self-interest is the primary driving force of nature. Self-interest is not, however, expressed only as rampant selfish behaviour. This is because all bodies, whether physical or living, are made up of constituent parts whose own survival depends upon the others associated with it, and so cooperation between the parts is necessary to improve the chances of the whole surviving longer. In general, it seems that larger associations possess a potential advantage which can place them in a better position to out-compete neighbours and last longer. In this way factors leading to cooperative association are one of the main forces in evolution. Some of the greatest advances have been achieved by the appearance of such cooperative relationships.

 

In living things there appear to be three levels of cooperation, which have led or are leading to new levels of complexity. The first is Symbiosis, which is the topic of this chapter. This is where two or more unrelated forms come together for their own mutual benefit, and can lead to a new level of complexity or way of living. Lichens are perhaps the best-known example: they are formed from an association between an alga and a fungus and can grow in places where virtually no other living thing can survive: such as deep in the Antarctic and on desert rocks. (Beatrix Potter, the Lake District author better known for her children's books, such as Peter Rabbit, was the first to recognise that lichens were built from a symbiotic relationship between algae and fungi.) There is now convincing evidence to show that cells arose by symbiotic associations between bacteria, sexual reproduction arose through symbiosis, and even the origins of animals and plants can be attributed to symbiosis.

 

In Chapter 8 another form of association, that of Social Organization, is considered which gave rise to multicellular organisms - this was one of the greatest advances in the evolution of life. It is also giving rise to a new level of complexity seen in termite and human society. The final level of cooperation discussed in Chapter 9 is that of Ecological Associations, where a gross but fundamental interdependence arises in an open system, even though it is founded on the unfettered selfish interests of all its constituent parts. It is a form of interdependence, which develops despite the driving forces of raw predation, parasitism and merciless competition for limited resources. It is interesting that such ecological associations have much in common with the way human society develops.

 

Knowledge of these associations suggests that a new level of cooperation can eventually emerge within an isolated, planetary society of intelligent, technologically literate beings. This new level is on a par with the evolution of the first complex organisms from single cells. But the cooperation is more complex than that, because it obviously extends beyond the living components, to include the artefacts we are creating. These are playing a vital role that can be likened to the amino acids in the suggested origin of life: they are the means by which the new order of complexity can come into being.

 

Our artefacts and us

Our artefacts may also be the end of us: it may happen that we are no longer needed for the new level of complexity to develop further. This end has been foreshadowed in the fate of the first form of life, in another hypothesis on an earlier stage in the origin of life. This proposes that life first appeared in clays based on silicon - these grew in complexity and eventually incorporated carbon compounds. The primitive silicon-based RNA-like structure was progressively transferred to carbon and eventually became the first true DNA. The carbon-based components then evolved more quickly than the silicon, which became superfluous and disappeared, playing no further part in the evolution of life. We are now in the process of passing control of the new level of complexity back to silicon: our silicon-based computers are already much more efficient than DNA-based brains at most tasks, and their rate of evolution is much greater than ours, so the force of natural selection could easily lead to DNA itself becoming superfluous. Our survival may depend upon us retaining our place in a fundamental symbiotic relationship within the developing world of our artefacts.

Symbiosis

There are many definitions for Symbiosis, with some even including parasitic relationships. Here it is taken that there is some mutual survival benefit involved in the relationship, like in the clams and bacteria. Symbioses are not easily evolved in the short-term, because the central power in survival is selfishness, so to enter into a mutual arrangement with another organism inevitably implies the existence of some altruistic component that confers the required mutual benefit.

 

The problems involved can be seen in orchids, which can only grow when seedlings develop a symbiotic relationship with fungi. When orchid seeds germinate they are so small little development can take place unless in the presence of the fungus, but even then many seedlings die. It has been found that many of the deaths are the result of something going wrong with the symbiosis between the fungus and orchid. In some the fungus grows vigorously within the seedling and acts like a pathogen, eventually killing it, together with the contained fungus. Here either the fungus cannot control itself sufficiently, or the orchid lacks the means to stop fungal growth, and both lose the chance for further growth. In other seedlings the fungus enters but dies: these seedling cannot gain the minerals normally provided by the fungus so also die. Here it would seem that the seedling exerts too strong a control over the fungus, or the fungus is too weak to withstand the environment within the orchid.

 

The surviving seedlings have a carefully controlled balance between the orchid and fungus, which favours both in the long run: the orchid grows and flowers with its roots supporting and nurturing the necessary amount of fungus. It would seem that only those seedlings, which have the right genetic make-up to manage the fungus population, have a chance of growing and producing orchid flowers: this may also apply to the fungus, which has to be able to grow in the root environment without becoming pathogenic.

 

When mutual arrangements like this can be worked out, they have great advantages, often allowing both participants to live in places where neither would be able to survive on their own. With orchids this symbiotic relationship is so successful that the orchid family has more species than any other plant, and they grow in places where few other plants succeed such as in the tops of rainforest trees and in desert regions of the world. (Part of the success may also be attributable to their unusual spore-like seeds, which are produced in enormous numbers and can be blown great distances. They also use specialist ways of achieving pollination which encourage speciation, such as attracting male wasps or midges by simulating the scent and/or features of their females.) The pisonia trees on Heron Island are in a close symbiosis with a basidiomycete mycorrhizal fungus in the soil, which helps the trees get minerals from the soil of the island.

 

Corals and clams

Corals, like the clams, have a close association with the bacteria which inhabit the cellular structure of the coral. These cyanobacteria use sunlight and carbon dioxide (some coming from the coral) to make sugars. Sugars are passed to the coral, while in return the coral provides the bacteria with the minerals they need: notably phosphorus and nitrogen. These minerals are in short supply in clean tropical waters, so are a very valuable resource for the bacteria. The system can break down when fertilizers wash into the sea, and large areas of coral have died in places where the bacteria no longer need the coral. Soft corals may use bacteria in another way - some use bacteria to produce a virulent poison. The poison protects the corals from predators and they can grow, safe from the coral-grazing parrot fish. But in nature, where there is a challenge, there is always something that succeeds - there is a snail which can eat gorgonian corals, a bird which can eat the poisonous monarch butterflies, and kangaroos which can eat poison plants containing the deadly fluoroacetic acid.

CORAL POOL. Coral reefs grow in clear tropical waters where nutrients are scarce. Bacteria grow in the coral providing food from sunlight while the coral provides carbon dioxide, nitrogen and phosphorus. When coastal waters become polluted from agricultural fertilisers or effluent, the bacteria leave the coral, and it dies.

Organelles and symbiosis

Lyn Margulis put forward the now widely accepted view that most of the complex organelles in cells were originally symbionts. She suggests that the origin of organelles goes right back in the origin of what is known as the Eukaryotic cell, about 2000 million years ago (these are cells with a distinct nucleus). Before that various bacteria had perfected many different biochemical processes, including some which had developed the mechanism of photosynthesis (probably cyanobacteria) and others that specialised in using the oxygen produced by photosynthesis. As well as biochemical processes, some bacteria also perfected physical tools such as the flagellum used in motion, which was achieved by building a special array of microtubules. (Some even produced the nearest thing to a wheel in nature: rotating projections - but the accidents of natural selection did not favour developing this technology until mankind came along and reinvented it).

 

Nobody knows how many of these ancient bacteria came to live together in symbiotic relationships, but similar associations can readily be seen today in some protozoa, especially kinds of paramecium, which have very complex symbiotic relationships with bacteria (they can be seen in the putrid waters of most splash pools). It is suggested that the bacteria initially came together in loose associations and as time passed they became more reliant on the relationship, with the survival of each dependent upon the biochemical or physical technologies of the other. The result was a growing complexity within the combined structure.

 

One of the early combinations must have involved cyanobacteria, which were probably used in a similar way to corals using symbiotic algae. The cyanobacteria started living within the associated bacterium, and over a long period of time lost all unnecessary features until today we see them merely as organelles - the chloroplasts in plants. Other bacteria became specialists in detoxifying and using the oxygen produced by photosynthesis as their energy source. These became associated with other bacteria, which could not use oxygen: the result was that the detoxifying bacteria became incorporated, and were eventually reduced to the organelles known as mitochondria. (The cells building human bodies are packed with mitochondria.) Those bacteria which became associated with mobile spirochaete-like bacteria became mobile themselves, and incorporated the technology of this mobility in the form of microtubules wherever needed. This association was probably one of the oldest, because the microtubules provide one of the most fundamental structural and intra-cellular communication elements found in all cells today. Better-known results of this association are the driving force of muscle fibres, sperm motility and the cilia projecting from the linings of our lungs.

 

These early symbiotic associations were successful because they gave bacteria abilities, which they would not have acquired by natural selection on their own. It was a means of combining technologies and producing a new level of complexity well beyond the capabilities of competitors. In some cases the DNA of the associated bacteria were combined, in others they remain separate. This is the case with the mitochondrial DNA, which is still retained outside the nucleus (it is interesting that it is only transmitted via the egg cytoplasm in humans, so men do not normally contribute to this part of human inheritance). Symbiotic relationships such as these provided a short cut to complex technology, because the technology could normally only come from very long periods of natural selection. Today such changes can be achieved more rapidly than ever before - we are learning how to do it by using genetic engineering, and are artificially introducing the technology of one species into that of another. These developments have enormous potential, and there is little doubt that they will alter the face of the planet. Human genetic engineering riding on the back of IVF has already added male mitochondria to implanted eggs.

 

The motile bacteria had many uses when combined with the evolving Eukaryotic cell - it allowed movement to take place within the cell as well as providing cell motility. Some of these motile units became associated with the concentrated DNA in the developing nucleus, and became the centriole. This is the organelle that divides and draws chromosomes apart during cell division. Centrioles must also have been a pre-requisite for the evolution of meiosis, the mechanism used to reduce the number of chromosomes in ova and sperm. They were essential for the evolution of sexual reproduction. How meiosis arose is purely guesswork, but it no doubt appeared in a stepwise process. Perhaps the first step was when cells joined together to pool their DNA. These diploid cells may have possessed the advantages over others by having DNA from both parent cells. However this doubling of chromosomes could not continue without the appearance of a mechanism for reducing them again, otherwise the number of chromosomes would soon become impossible, if they went on doubling.

 

Origins of sex

The advantages of sexual reproduction, raised in Chapter 5, are thought primarily to have been as a means of combating viral disease. It accelerates the acquisition of immunity and has the side effect of combating other mortality factors presented by a changing environment. Whatever the reason, the evolution of sexual reproduction has lead to an enormous advance in the rate of evolution, and a burgeoning of the complexity of living things. Gametes from different species cannot usually combine to form viable offspring, because the genetic differences between the two sets of genes lead to a lethal combination or a sterile cross. Biotechnology can override these problems and specific genes which code desirable technology can now be taken from one species and inserted into another without affecting its ability to reproduce, or imparting any of the disadvantages of inbreeding. Starkly put, we can now implant a beneficial chimpanzee gene into a human egg without the risk of producing a sterile monster offspring. Before biotechnology this could only have been theoretically possible, by cross-mating or in vitro fertilisation, both of which are culturally unacceptable. Such ethical considerations do not apply to our manipulation of domestic animals and plants, and any means of improving their value are usually quickly applied. Inter-specific crosses were widespread before genetic manipulation, such as in mules and many garden plants, but there is still some justifiable vacillation over gene transfer.

 

Ethics and cross breeding

Our ethics on cross breeding partly come from the distant past, having a grounding in the chances of survival of offspring. It is not something confined to intelligent religious beings. It is based on the fact that it is no use wasting reproductive effort on young ill-equipped to survive This is a principle which applies to parents that are too closely related, as well as to inter-specific matings. The situation becomes confused in liaisons between varieties and subspecies where crosses can be very viable, but culturally frowned on. Most wild dogs will kill domestic dogs rather than mate with them, unless their society has been destroyed by human intervention. Human race or cultural crosses were similarly treated in the past. Unnatural conditions lead to unnatural alliances, especially when confined in zoos, where crosses and unlikely attempts regularly occur. Few restraints remain on human sexuality but one is still taboo even in western society. This is the physical act of sex between humans and animals. It is the subject of jokes, but is treated so seriously by legislators, that penalties are far more severe than for other sexual demeanours. Nevertheless, bestiality is probably common and widespread, at least with domestic animals. It seems reasonable to suppose that chimpanzees and other primates are also frequently targeted (there are no publicised records of offspring, but it may not be possible for embryos to develop normally).

 

Scientists have a habit of coming up with knowledge which questions long accepted ethical and religious teaching. Galileo is the best-known example. The in vitro use of genes from humans in the eggs of pigs, to produce better hearts for transplant patients, questions what we mean by bestiality - what are the limits, why do we object? Where is genetic engineering leading us? Our role in bringing about the crises of BSE and the human form of CJD are warnings that we should heed scientific whistleblowers. Knowledge that up to about one percent of the human genome is made up of specific retroviruses is a serious warning that there are dangers in transgenic work between us and other species, which no doubt have different viral inclusions. The taboo over bestiality may be based on a deep-seated fear of spawning monsters. Transgenic work is full of latent dangers, far worse than producing the odd monster or two, but natural selection has not endowed us with any innate inhibitions about tampering with eggs under the microscope.

 

Plant-animal associations

Walking around Heron Island, there was much to see apart from the marine environment. The pisonia trees were full of noddy terns and we found some young ones stuck on the ground. They were unable to fly because the seeds of the trees had glued their wings together. This is a rare adaptation in plants. Plants are past masters at using animals to transport their seeds, but there are few fruit-eating birds on oceanic islands, so these trees can only succeed if they stick their seeds to the outside of marine birds. The birds carry seeds to isolated treeless islands and later get their reward when the trees grow and they can nest on the island. The silvereyes do eat berries, and help disperse figs and other trees. They must have come to the island a long time ago because they have evolved into a distinct subspecies, and they are on the way to becoming a new species, like Darwin's finches on the Galapagos.

NODDY TERN ON NEST. Plants are very good at using animals in a number of ways. One common use is to disperse seeds - many producing berries which attract berry-eating birds. The pisonia tree grows on coral islands where there are often no berries, and berry-eating birds do not fly between isolated islands, anyway. Noddy terns nest in trees and regularly land on isolated rocky islands. The trees have evolved the rare technology of sticking their fruit to the bird's feathers. The trees return the favour by growing suitable nest sites for the birds.

Other inhabitants of the island included termites, which are adapted to eating wood, and a couple of tame young kangaroos. They used to have mock battles, wrestling with one another under the fig trees. Many termites have symbiotic bacteria, fungi or ciliates in their guts, which help them to digest otherwise useless plant material; while the symbiotic microbes in ruminant animals and kangaroos are also able to break down indigestible plant material and re-use nitrogenous waste instead of voiding it in urine. Rabbits nurture microbes in an enlarged caecum and gain nutrients and vitamins from eating their own faeces. In these symbiotic relationships the microbes are just as dependent upon the animals for their survival, as the animals are on them, with many microbes only known from the gut of ruminants. Biotechnologists are now manipulating these organisms so that domestic animals can be given bacteria with better qualities from other species, or engineered varieties, which can detoxify plant poisons, such as fluoroacetic acid. This has been done with the aim of allowing domestic animals to graze in areas containing poisonous plants, competing in Western Australia with the already immune kangaroos.

 

Domestic associations

These symbiotic relationships suggest a better understanding of our own situation, because we have, in effect, developed the most complex of all symbioses. The only difference is that we keep our symbiotic organisms outside the body instead of in the gut. Other species have done this, but not to the same extent. One family of tropical termites, common in SE Asia and Africa, instead of keeping microbes in the gut and eating wood to feed them, makes cakes out of the chewed-up wood within the climate-controlled nest. They carefully tend the cakes to grow fungi, and the symbiotic fungi return these favours by growing nutritious fruiting bodies. With this technique the termite's diet is composed of small quantities of highly nutritious fungus, instead of the volumes of wood consumed by their cousins. The fungi do better than most symbionts because they can break down wood lignin. Similarly the leafcutter ants seen in Guiana have developed the technique of building compost heaps from cut-up leaves where they grow another domesticated symbiotic fungus. These relationships make it clear that our association with domesticated species is also a classic example of symbiosis.

KANGAROOS PLAY FIGHTING. These kangaroos on Heron Island have ruminant-like digestion where they use symbiotic microbes to digest their food. These microbes are used as if they were internal domestic animals.

TERMITE FUNGUS GARDEN. Planting and cropping domestic plants has been done for millions of years by insects. These termites have a fungus garden created out of chewed wood, which they tend and weed, much like we attend to our crops. Such relationships do not need intelligence, and everything points to our use of domestic species being more one of the plants and animals making use of us, rather than us using our intelligence to make use of them.

It might be argued that our association with domestic animals and plants is not a symbiosis, because we use our intelligence to enslave other species instead of the relationship growing by the process of blind natural selection. However, a closer look at our history suggests that there is little difference - most of our domestic animals and plants did not become domesticated by conscious effort, but by a process of blind natural selection. The foods chosen by animals inevitably exert a force of natural selection on the species eaten. Many birds, like the silvereyes, eat berries, and will eat berries from many different plants. Plants respond by using the birds to carry their seeds and adjust flavour, colour and nutritional value to encourage birds to eat them. Sometimes a closer relationship develops between a single species of plant and a bird. A tree in Trinidad has a bird that feeds exclusively on its fruit. The fruit is green and unpleasant to other birds, but, to the bird domesticated by the tree, the fruit provides a complete year-round diet (the fruit could have ultraviolet colour which only birds can see). The selective force on foods by mankind has had a similar effect, since we became the dominant on the planet. We have become like the Trinidad bird, diverting the course of natural selection towards use by mankind alone instead of the combined selection of many species previously.

 

There seems to be little doubt that most domestic species, both plants and animals, arose through a long process of natural selection between resident human populations and the animals and plants in the countryside they occupied. Little conscious selection was involved, we were just acting like any other animal, continually choosing food items which were either the most easy to obtain or which had the better flavour. This brought the seeds of the favoured plants to dominate around human settlement, and the more fearless prey species to become commensal. It appears to have been a very long time before people realised that they could plant and harvest crops and there seems little to suggest that agriculture arose as a conscious, intelligent act. Ants and termites have been doing it for millions of years, and they are not regarded as intelligent. Early stages in the development of domestic relationships are seen from Australia where Aborigines returned part of tubers to the ground. Studies suggest that this was not done to plant crops for the next season, but to placate spirits. Similar acts are performed in modern western societies when part of the harvest is often presented as an offering.

 

Peoples who had a more nomadic existence were less likely to concentrate choice food items and so had less likelihood of having plants lock onto mankind and enter a domestic relationship. (These peoples, such as Australian Aborigines and African Bushmen are often said to be primitive because they have not domesticated plants. This is entirely a wrong interpretation - it could be better interpreted that by moving around they have avoided becoming slaves to plants.) Hunted animals did not become domesticated until much later, because the process of natural selection probably did not favour this until there were large areas of domestic crops open to pest species. Many became adapted to the anthropogenic environment, some remain as pests today, such as sparrows and rats, others slowly entered a domestic relationship, such as sheep, rabbits and guinea-pigs. These animals would find higher quality feed near mankind and gain protection from their natural enemies, making the selective predation by mankind a worthwhile trade-off.

 

Intelligence was undoubtedly necessary to catalyse the evolution of the domestic relationships, but only after plants and animals started to become dependent upon mankind for their own survival. Even today, with all our technological knowledge and intelligence, very little thought is given to developing new domestic species - virtually all our agricultural and animal husbandry research is centred upon species which developed a domestic association with us thousands of years before people even knew they were becoming farmers.

 

The domestic association with mankind probably evolved much more quickly than other symbioses, and it has led to some serious problems, which we are only just beginning to redress. In long-term relationships, like the tree and the Trinidad bird, both parties have all their needs fulfilled. In the human relationship, populations rapidly became dependent upon single crops and a few domestic animals, and no knowledge existed on the importance of a balanced diet. Compared to the rich and varied diet of the previous hunter-gatherers, Neolithic peoples subsisted on a very impoverished diet, and there was a dramatic decline in stature and health brought on by the cultural change. It is only now being redressed in westernised societies. The Neolithic was marked as a time of rapid natural selection for individuals who could survive on such poor diets. It also selected people for other traits, such as those who could cope with bovine casein, and the use of alcohol was probably another early selective force. Symbiotic bacteria in the gut also probably became more important, helping to redress the impoverished diet. This may have given added importance to the human appendix, which helped seed the hindgut with useful bacteria, including Escherishia coli.

 

A characteristic feature of some of the most successful symbioses is that they dominate the available resources. Coral forms an almost complete ecosystem in coral reefs, termites dominate many grasslands where they may consume most of the grass production, in the same way that other grasslands are consumed by ruminant animals via their gut symbionts. Leaf-cutter ants are dominant on the floor of new world tropical rainforests, harvesting tree leaf production. It is interesting that this is an unusual trait for ants, which are normally carnivorous. They could have transformed the globe if they had been given enough time, diverting most of the world's leaf production to their compost heaps, and out-competing most other herbivores. It is now too late for them, because we dominate the planet's ecosystems with our own managed domestic species, and this domestic association is at the root of the arrival of the new technological age. It is doubtful whether ants could have made this transition!

 

Abilities lost in symbiotic relationships

We can get an idea of how our symbiosis may proceed by looking at examples of long-term associations. It is often the case, that the species which may be regarded as the one in domestication, loses many of its original characteristics. For instance the termite fungi have lost the ability to produce fruiting bodies, making it difficult for mycologists to know to what group of fungi they belong - the bodies they do produce are merely food parcels, which contain a complete diet for the termites. In the same way, going further down the scale, the bacteria which gave rise to chloroplasts and mitochondria, are no longer recognisable as bacteria, as they are now merely internal organelles. Our domestic species are systematically being modified to over-produce whatever product we are most interested in and they have lost the ability to survive in the natural environment. Significantly, it has been found that the brain size of our domestic animals has declined relative to their wild relatives. This has all been achieved by natural selection, initially with little conscious effort, although we now use every tool available to achieve higher productivity. This process of conscious selection should, perhaps, also be regarded as natural, because the arrival of a conscious species is the inevitable result of natural selection on living things.

 

Few realise that we have now reached a fundamental turning point with our domestic species - in fact with the whole range of other living organisms on the planet. We are now learning how to do things which it took natural selection billions of years to achieve; that is to make our symbiotic species produce only the products we need and not all the other wasteful aspects of them having lives of their own. An extreme example of our current wasteful methods can be found in sheep used for wool production, or our use of cattle for beef production. Hectares of vegetation are needed to provide enough food for the sheep with much of it being unpalatable or wasted. Tonnes of this vegetation have to be eaten by the sheep to feed their symbiotic rumen microbes. The microbes grow and use up energy, while much of the remainder (mostly lignin) is passed out in the faeces. Some of the energy is kept by the sheep digesting some of the microbes or by absorbing the volatile fatty acids they produce. This is partly used to build body tissues, but most is lost in producing heat, or in the energy used to roam around grazing. Only a minute fraction is converted into wool.

SHEEP IN PADDOCK. This is the old technology - of using domestic animals to produce meat and wool. It is incredibly wasteful, with only tiny amounts of product being produced from huge amounts of vegetation. Biotechnology has the potential to replace most of this traditional technology, and produce products more directly.

Future biotechnology

The new era we are entering will increasingly see such products being made directly without all the intervening points of energy loss. In this new age of biotechnology we can gain the gene technology of all living things. It is likely that products, such as animal proteins and plant carbohydrates could soon be produced in bulk, using bacteria with genes implanted from our domestic animals. Fibres, wool and many other products could also be produced, short-cutting the wasteful plant or animal we now use. In short we will have direct access to the desired technology contained within the domestic species without the continued need for the originating animal or plant. The productivity per hectare could be vastly increased using this technology - one likely method would be by using fast growing algae as the base material, and processing this product with genetically manipulated bacteria to produce anything from cellulose fibres (already done) and starch grains, to animal proteins, silk and perhaps even wool. This is the natural pathway for an intelligent, technologically literate society, and we can now be free of our slavish dependence on keeping our symbiotic domestic animals and plants - all we need is access to the technology they possess. This technology could support many times the present human population, but this can only happen if we are able to embrace the new culture and somehow acquire a level of social responsibility beyond anything remotely available at present.

 

With the use of genetic engineering and biotechnology, the plants and animals domesticated in Neolithic times will increasingly be seen as interesting examples of a lingering pre-historic technology. The new technology will be much more adaptable, picking valuable processes from a vast library of genetic resources. This library is to be found in the Earth's remaining carbon-based life, with each species of animal and plant, microbe and fungus containing potentially valuable gene technology. This technology can be expected to be progressively incorporated into the new society, and gradually displace the wasteful symbiotic sheep, cattle, wheat etc. of the past age.

 

Our artefacts - the new symbionts

While we have been acquiring the technology of our symbionts for our own purposes, we have also been unconsciously creating new symbionts. We are translating DNA technology and transferring it into inanimate objects, our artefacts - and they are thriving. As time goes on they have been acquiring more and more of the characteristics of living things, and everywhere exist within our society, performing tasks for us, while we scurry around looking after their every need. Increasingly we are finding that they perform better if we add some controlling unit: an incipient brain. Our cars, microwaves, VCRs, and alarm systems all already have microchip controls. Computers are now usual household appliances and society is organised in every sense by mainframes. Computers are regarded as aids to human intelligence, but, as we know, it is only a matter of time before truly intelligent computers will evolve and be plugged into the developing global control network.

 

As appliances become more intelligent, and more linked together, so we will become less in control and less important in the symbiotic alliance. We are likely to be progressively relegated to being operatives in the new complex, and effectively become internal symbionts in the new developing organism. As such we run the risk of losing unnecessary characteristics, as the bacteria did when they became organelles. Our domestic animals already have shrinking brains and we could follow suit. It is disquieting to find that our brains have already shrunk - early man had larger brains. It has been suggested that this indicates that our brains have become more efficient, but another interpretation might be that our use of domestic species made us lose the need for some of our former intelligence. It is being further eroded as we lose the need for many of the old powers we used to have. Reference books mean we no longer have to memorise stories and important texts, pocket calculators remove the need for basic numeracy, while most of us probably lost the mental ability of living off the land, in a predator-infested natural environment, long ago.

 

Before we left Heron Island we went out at night to watch a green turtle laying its eggs. It carefully dug a deep hole with its hind flippers, and then laid a large clutch of eggs. In the morning the nesting site was well covered over, but the turtle's tracks gave it away. Getting on the ferry we saw several turtles, lazily swimming over the reef, picking seaweeds off the bottom as they went past, occasionally bobbing their heads above the waves to gasp air. How could one guess that such things could come into being, if one lived billions of years ago and the only information one had was that certain kinds of bacteria were beginning to develop a symbiotic way of life?

 

The enormous rate of evolution in machines compared to DNA suggests that intelligent machines will soon take over from our limited human brains. The chances of such a primitive organism as mankind remaining within the symbiosis are not good. How the machine world develops after that is perhaps unknowable at present. We could well become so marginalized that we no longer take part. Silicon will regain its domination and leave DNA evolution for dead, in the same way that DNA may have taken over from silicon in the early stages of life on Earth. It would be interesting to know whether intelligent machines will be endowed with inhibitions against one of the most dangerous of activities - that of making self-replicating machines. Chimeras between DNA life and mechanistic constructions could well be made that can reproduce themselves. This means they would enter a process of natural selection for survival. Our nano-technologists would dearly like to make such things. We already have computer viruses, which can reproduce and evolve - the new life could become disease organisms and pests in the machine world. They would also have the potential to eventually evolve into something as beautiful and complex as the life on the Great Barrier Reef.

 

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Part III ASSOCIATIONS (B)

Contents part 3
Main Contents

HERD OF ELEPHANTS. Elephants have complex societies based on the relationships built up over many years of experience by the matriarch of the group. A society is a form of biological association: it is basically an aggregation of individuals possessing some form of linkage or communication that produces a structure which has a greater whole than the sum of its constituent parts. Here we look at animals which have been in complex societies for a much longer time than we have. What can we learn from them about our own society? Can we extrapolate this knowledge into the future development of a world dominated by machine intelligence?

 

CHAPTER 8

SOCIETIES

Ghana

In 1958 I set sail for West Africa on a cargo boat with an enthusiastic group of young people, excited at the prospect of seeing animal and plant life in the tropics. The boat had a severe list to one side, particularly when crossing the Bay of Biscay. We were told that it had spent the war at the bottom of Takoradi harbour and had never been the same since. We wondered whether it might tip over: apart from our fears, it would have been a problem for the Nkrumah Government because the boat was carrying the new Ghanaan currency. The Canary Islands were a disappointment, because we had expected tropical weather, but it was cool and the air was a thick white haze of Sahara dust. However, further south we soon throbbed into the tropics we craved, where the sea was a brilliant turquoise - a colour we had never seen in the cool, plankton-laden, ultra-marine waters around Britain.

 

We soon found the bows a marvellous place to see ocean life. Dolphins played in the bow-wave, sometimes leaping in the air for fun, and flying fish streamed off for hundreds of metres, often dipping their extended lower tail fin into waves to power a further glide. Sometimes groups of what looked like pink fish jumped out and flew over the waves in a similar manner. It was hard to see what they were, but with binoculars we were surprised to see that they were in fact squid with wing-like flaps. Nowhere had these appeared in our zoological textbooks. Sometimes we saw hammerhead sharks and everywhere there were the large bottle-like floats of Portuguese man o'war jellyfish and lumps of floating sargassum weed.

 

After disembarking at Takoradi we were able to have a walk on the beach. The grey sand had black streaks in it and was too hot to walk on with bare feet. We came across some of the jellyfish washed up and I found that they do indeed have a severe sting. The black sand was fascinating to watch as it moved with the waves - it was sorted by the flow and collected in ripples and lines as the waves receded. I put some in a container and later had a chance to look at it under a microscope. The sand was all made up of crystals; the grey grains were mainly quartz while the black ones were probably titanium oxide.

 

Crystals as mineral societies

It is interesting that crystals can be regarded as a form of society developed in non-living matter, they are beautiful, mathematically organised structures which are well in advance of their constituent molecules. Apart from many other properties, the coordination of molecules into massive crystalline structures enables them to partake in new levels of physical and chemical organization. For instance, in cooling granite, silicon and many other elements are involved in an active chemistry. This progressively changes as crystals form and remove molecules from the environment. In this way even quite uncommon elements become concentrated into discrete crystals. Later weathering processes on the rocks yield new aggregations, which are again the result of the crystalline structure. Resistant crystals remain and are blown away by the wind, often concentrating silica in the form of sand dunes. Subsequent wave action, like that seen on the Takoradi beach, may have further effects, separating heavier crystals from silica sand, yielding deposits of minerals containing the relatively rare elements of titanium, thorium and zircon. None of these massive concentrations would occur without the initial aggregation of molecules into a crystalline form.

 

Cells to organisms

In simple living things, linkage is the inevitable result of reproduction by division - when division takes place the two daughter organisms must at least be briefly in contact with one another. This can be seen in coccal bacteria, yeasts, and simple algae. Early associations such as these must have lead to the evolution of relatively complex aggregations of cells. These aggregations then moved on to become organised societies of cells, and finally became the first organisms. Many algae today show some of the early stages, some continuing cell division until they produce long filaments, others grow into more complex plates, spheres or branching structures. The seaweeds have developed further, acquiring advanced differentiation between cells and the growth of functional organs, such as the holdfast in kelps and the floats of the sargassum weed.

 

The process leading to the coordination of individual cells into organisms was very slow - it took billions of years for simple animals and plants to evolve from unicellular beginnings. Initially there was presumably natural selection for an increasing amount of contact and communication between the individual cells. Then slowly, by a developmental process, a division of labour appeared. This produced cells which perform different functions according to where they are in the organism, such as found in seaweeds. This process inevitably leads to some cells performing functions which make them prepared to risk their lives for the good of the colony. From such simple origins it would be hard to predict that they could develop into the complex integrated societies we see today where the Earth is now covered by units made up of billions of cells. The flying squid, hammerhead sharks and dolphins are all such societies. Some become huge, like the whales and giant redwood trees, others are units capable of running, climbing trees and operating computers. Each one of us is made up of such a society.

DOLPHIN IN BOW-WAVE. There are some very complex societies which have perfected organization of billions of individuals into a superb functioning unit. One of these societies is represented by this dolphin, which is riding the bow-wave of the MV Sangara. It is made up of billions of cells, most only with short lives, during which to perform their allotted tasks helping to make the whole work as a unit. This demonstrates that the organization of billions of units into a functioning whole is possible.

Super-organisms

A similar process can also occur with organisms, leading to another level of integrated society. Many lower organisms reproduce by budding in a similar way to microbes, and if the daughter organism does not separate, there may be selection for the clone of individuals to cooperate and build a super-organism. This has happened many times in the Coelenterata whose complex societies include massive corals, and sea pens. The Portuguese man o' war jellyfish is probably the peak attained by this mechanism, where each highly adapted part - tentacle, float etc, is made from what would normally have been a whole organism. Other integrated societies of organisms existed in the past, including the graptolites, which became extinct over 400 million years ago. In higher animals other forms of association develop with the need for females to nurture and educate offspring and for males to protect their females and young from predators (and other competing males). These behaviour patterns lead to the formation of extended families and tribes, which are also on the pathway to developing into super-organisms. Human society has developed into many super-organisms - families, clans, tribes, nations, empires. Historically these super-organisms have been constrained by geographical barriers, such as mountain ranges and seas. Modern communications have overcome these barriers, despite residual tribalism and attempts to make nations continue to have real boundaries.

 

Global organism

With modern human society it would appear that there is only one possible successful outcome and we are already well down this developmental pathway. We are in the process of amalgamating into a new global organism. Instead of billions of cells this organism is made up of billions of human beings, together with our domestic animals and plants, our tools and artefacts, all living together in a symbiotic association. This is probably the only successful result, wherever in the Universe that billions of intelligent organisms develop the technology necessary to become coordinated into planetary unities. If it fails to develop, escalating rivalry between tribal units inevitably ensure mutual extinction, because technology soon perfects cheap and easy weapons of mass-destruction, and the world is full of people prepared to use them.

 

Natural selection is usually thought to be the main means of evolving new structures and the pages of history are full of the apparent natural selection between rival societies - there being an uninterrupted succession of conquerors and wars. But with human society the physical constraints of the globe have already forced us into one unit, whether we like it or not. Now the other mechanism of evolution, development, appears to be the overriding principle and turmoil between societies is only one of the mechanisms leading to this developmental change. The new structure is progressively emerging from an apparently chaotic, competitive turmoil. The new order is progressing like the gene pool of a species, but instead of genes, it is the re-assortment and accretion of our culture and artefacts. This development would take DNA billions of years to achieve, but with the catalyst of intelligence, we can develop the new order within only a few lifetimes. We have now virtually reached the point when all the mechanisms are in place for the new organism to be born.

 

Organization in DNA societies

Knowledge of how DNA societies are organised may give clues as to how the new global organism we are creating is likely to be held together. There is still a great deal of mystery about how the billions of cells in a living organism can be coordinated into a single entity, because the complexity is too much for us to grasp. Physical details are simple enough, with cells having been allotted to particular functions - muscle, bone, blood, nerves etc. and perform their duties as required. Reproduction takes place, but once cells have been given their allotted function they cannot change, and in most cases they are fixed in their locations as well - no travel is permitted. This suggests that a successful avenue towards producing an organised society is via fixed professions and an unquestioning dedication to duty. However, cells do get it wrong and the body does require complex policing systems - these involve mobile cells which can move through tissues checking the identity cards of all the cells they encounter. Any cells that are found to be suspect, or show signs of deterioration from age or genetic defects (e.g. cancer) are marked and removed by teams of operatives in the immune system. Another avenue for control comes from the suicide gene, when unwanted cells can have their self-destruct mechanism activated. Foreign bodies and bacteria are also quickly dealt with.

 

The body is maintained as a whole by transport and communication: the gross aspects of blood circulation, hormones and nerves are clear, but another more basic level is probably much more important - this is the communication between neighbouring cells. It took a very long time for organisms to develop this in the first place, and it was probably the major hurdle for them to overcome. It involved the creation of the cell wall, which has an incredible ability to control the movement of molecules across its boundary. With this it can communicate with other cells in its environment, especially by microhormones (including the antidote to the suicide gene). Cells may also use other means of communication such as electromagnetic radiation (photons), electrostatic potentials and ions. Living cells are therefore in constant conversation with their neighbours and group coordination between cells becomes possible. This presumably allows cells to become organised into complex organs and coordinate their activity to perform gross functions. Communication between cells is much more continuous than we can achieve with our pedestrian communication skills, however computers are able to do this faster and in more detail than anything else known in nature. We know relatively little about how cells are coordinated in organs. More is known about how super-organisms are organised in insect societies.

 

Insect societies

From Takoradi we travelled by train to Kumasi about 300 kilometres inland. We sat in the lounge-like last carriage watching with excitement as each scene slid past the windows and receded into the distance. There were pastures with strange cattle in them, cacao plantations, villages with smiling children, and patches of residual rainforest. All the way we went past termite mounds, studding the embankment like milestones. At Kumasi we were taken to Bobiri Forest Reserve where we were to stay. It was a residual area of forest that had been logged, but full of wildlife, particularly insects. The entomologists were excited over the butterflies - there were so many of them and so many different kinds. The charaxes were particularly challenging, because they flew so fast they were gone before one had a chance of seeing them. We soon found that they came to feed on the ground, not to flowers but to rotting fruit and animal excrement.

 

The first night we had a chilling experience - at about two in the morning we heard a noise which could only be described as if someone was being seriously assaulted or murdered. The screaming went on for many minutes, only to start again sometime later. In the morning we timidly asked what it was, and were told - with a laugh - that it was a tree-bear or tree hyrax. The dead of night is the right time for sound to carry and for night animals to proclaim their territory.

 

I found one tree with its trunk and branches swathed in silk and living underneath was a huge colony of booklice. These are one of the many families of insects which have developed a social way of life. Another night I went out looking for animals and heard a pervasive hissing sound in the trees next to the track, bush crickets were flying out and frogs hopping away. Then I saw the whole area was seething with driver ants. They form huge mobile colonies, which sweep through the vegetation en mass, killing anything they can. I watched them swarm over a land crab, making it writhe in a hopeless attempt to escape. Then I felt a bite on my leg and I was horrified to find that I was standing in the middle of a column, which was well and truly on its way up. I ran fast, until well clear of the area, and then set about knocking the biting ants off my shoes and socks.

TERMITE MOUNDS AND PANGOLIN. Termite mounds have to be very tough to resist termite-feeding mammals, such as the Aardvaak and Pangolin (pictured) in Africa, the Echidna in Australia and Giant Anteater in S. America. The mounds are complex buildings with an efficient ventilation system, enabling termites to control their climate and live in places where the climate would otherwise be unsuitable.

Termites

One of the challenges we had was to dig out a termite mound and to find the queen. When we first found a mound we thought it might be easy, "after all they are just made of earth". Kicking a narrow turret soon demonstrated that the termites had more technology than we thought. A bruised toe showed that the earth is well cemented together. The spade we brought was useless and even the pickaxe had little effect - with a full swing it just made a dead thud, only penetrating a few inches. The termites had had millions of years to perfect their protection against anteaters.

 

Eventually we did break through into the centre to where the termites were culturing their fungus gardens, but not without getting a few bites from the large soldiers. They have sharp jaws, which slice through skin like scimitars and cross over locking shut - we were told that local people used them to hold skin together over deep wounds. Right in the depths of the nest we found the queen chamber set at about ground level. It was probably where she first founded the colony. We took the chamber out and cut it in half with a hacksaw. Inside we found the huge white pulsating sack-like body of the queen with a normal looking termite head and thorax attached at one end. She has become nothing much more than an egg factory, like a parasitic tapeworm in the gut, but she controls the whole colony. Running around beside her was another termite, and it turned out to be her original male consort. He was still needed by the queen to perform his sexual duties many times a day.

 

Insect societies have been in existence much longer than any vertebrate society and can give a better view of where societal organization can lead. This is because insects have so many species and such short generation times that the chances of them evolving complex societies are much greater than in most other animals. Altruism is the main characteristic of insect societies - individuals spend their lives in the service of the colony, defending it to the death, if necessary. A similar development was required for single cells to become organisms. Cells needed to develop altruistic tendencies, including becoming soldier-like macrophages prepared to give up their lives in defence, or committing suicide to produce building blocks in the appropriate place, such as fibres in the forest tree-trunks. In insects these activities range from foregoing reproductive potential, to the soldier kamikazi-like attacks on anything which threatens the colony.

QUEEN TERMITE. The caste system in termites is fully entrenched. Here is the founding queen with her hugely distended body, forever encased in a prison-like cell where she has been transformed into an egg factory. She also delivers hormones or pheromones which control the whole colony - how many young become workers, soldiers, or alates ready to fly off to found a new colony. She is accompanied by her 'king' who continues to mate her. The soldiers have huge jaws to kill ants and bite ant-eaters. They are programmed to attack unthinkingly whatever the odds to defend the whole colony. All non-royal casts are both male and female - there is no sex discrimination.

Professions and castes

An essential part of this development is that the individuals, like cells in a body, take on discrete professions and acquire the refined tools needed to carry out their allotted tasks. These vary according to species; in bees it is age-related - they start adult life as nursery maids and end up as foragers. Other species use diet as a means of controlling the growth of body form. They know all about the equivalent of protein diets and steroids for body-building. They can use starvation diets to produce mini-workers designed to repel parasitic flies, and good, heavily laced diets to produce well-armed soldiers. Overall control comes from the queen, mostly via chemical messengers, which are exchanged between all members of the colony. These have many effects, one often being to prevent workers from developing into queens. The queen may also actively coerce workers into activity.

 

Colonies appear to have an intelligence above that of the individuals, somehow knowing when to adjust the numbers of particular castes, when and where to forage and how to adjust the nest climate. Bees have even been found to raise the nest temperature when threatened by a fungus infection, in much the same way as the human body reacts to disease. They have also recently been found to have skills well above what was thought to be possible for insects, especially those involved with navigation and learning - they have even been found to possess some basic cognitive abilities. The colonies act as if they were a single body.

 

It is thought that frequent social behaviour in ants, bees and wasps is a result of their method of sex determination. Without going into details, the sex determination method means that daughters are much more closely related than in other insects. This means that, although not clones, they are sufficiently genetically close for altruistic behaviour to evolve. This happens because if a sister has almost identical genes to yourself, and can carry on your genetic line if you die, there is a natural selection advantage to risk your life to save her. Similarly, individuals can safely give up their reproductive function for the sake of the colony, because the sisters they tend will found new colonies. This has led to female societies, where males are only produced for the function of a once-only sexual act with a virgin queen. A similar close relatedness is probably also responsible for the appearance of social structure in aphids, which produce clones of identical offspring. Some aphids have gone as far as evolving non-reproductive soldiers to protect the colony.

 

In many respects ants are more advanced than bees, sometimes building massive colonies with complex divisions of labour, as in the driver ants and the leaf-cutter ants of Central and South America. They are also advanced in another respect: many species form new nests close to the parent colony and retain ties with it. This budding process may continue to produce an extended society controlling a large area. They develop many town-like nests and a complex network of communication lines. Little is known about the longevity of these societies, but anecdotal evidence suggests that they may well last for hundreds of years.

 

The main factor that holds most ants back is that they remain hunter-gatherers. Only leaf-cutter ants have succeeded in a more direct exploitation of solar energy resources, using domestic fungi to convert green vegetation into food. Termites had already achieved this advance before they became social, because their cockroach ancestors have symbiotic fungi, bacteria and protozoa in their bodies. Termite social life probably began when some built protective mud cells around food sources, somewhat like the simple social structures seen in web-spinners (Embioptera) and some book-lice (Psochoptera), which build communal homes under silk webs. Both these groups resemble termites in that their colonies include males - termites do not practice sex discrimination and have equal numbers of males and females in each caste. Termite constructional technology has become one of their main features, building massive nests where they can control the internal climate, which enables them to live in areas well outside their preferred climatic range. This controlled climate also allows them to shed clothing (thick cuticle) and concentrate on productivity.

 

Mammalian caste

The remarkable thing about insect societies is the apparent dedication to duty, where they stick to their allotted tasks, and do them until they die. The slavery and impotence usually seems to be enforced by some form of pheromone or hormone, which is produced by the queen and passed on between the workers. This is one of the things that happen when they stop to touch antennae or beg for food. The social organizations of mammals and birds have nowhere gone so far, but many have developed a king and queen structure with the remaining members relegated to menial jobs of maintaining territorial boundaries, killing prey and helping rear the royal young. In most cases this is only a loose arrangement, with other closely related males and females also involved in reproduction to some extent. Molerats are the only mammals known to have proceeded further along the social insect path - these are a naked, termite-like, subterranean animal which produces a genuine worker caste, attending the queen and her consorts. This demonstrates that mammals can take the insect path and perhaps also shows that we should take a closer look at human beings. We are also naked, like termites!

LAKE BOSUMTWI. Scene at the meteoric crater lake in Ghana. Two hundred years ago or more we could not have come here like this. We would have been made into slaves if not killed outright. Human society is well versed in how to turn people into required castes.

Lake Bosumtwi and Archaeology

We could not leave Ghana without seeing Lake Bosumtwi. We went on a day visit, travelling north into the savannah zone, where in the past there would have been teaming wildlife, elephants, gazelles, lion. But they had mostly long since gone. The country was well populated by people and was the home of the once feared Ashanti tribe. The lake is one of the wonders of the planet, being a crater formed by a celestial impact, like the crater in Arizona. It is about seven kilometres across and filled with water. The impact vaporised most of the material in the crater, but spewed drops of liquid rock over West Africa as black, glass-like tektites.

 

We walked through cacao plantations down to the lake accompanied by a band of excited children, amazed at such strange people doing such strange things. We had more help than we wanted in wielding nets to catch dragonflies - they all wanted a turn! But we had a lot of fun, everyone was very friendly and we learnt a lot from the local teacher. Things would not have been the same a few hundred years ago, when Africa was divided into many despotic kingdoms, much like Europe during its warring past. We would have been killed, or sold into slavery. The slave trade was in full swing, long before Europeans began buying slaves to take to the Americas. Neighbouring Nigeria has the largest archaeological site in the world - longer than the Great Wall of China and with more earth and rock moved than was used to build the Pyramids. It shows the power and organization in Africa present about 900-1300AD, unthinkable to the Europeans who knew they were the only race capable of great works. It was built as a pest control measure to keep elephants out, and really puts the Australian rabbit-proof fence in perspective, the Western World's best effort!

 

Elephants are wonderful animals - huge relics of the ice age fauna, the peak of the world's mammalian megafauna. We have only a slight inkling of the complexities of elephant societies. They live so long and have such long memories that we cannot interpret their actions without knowing about their previous history and experience. It has only recently been found that they communicate over great distances using infrasonics - deep sound waves travelling through the ground, rather than in the air. They can recognise individual calls and remember them even after 12 years of separation.

 

Human Societies

Human societies have tried most of the strategies previously used by DNA to create stable, successful social organizations. But instead of using DNA programming, mankind has used intelligence to acquire the innovations in a very short period of time. History is full of Kings and Queens, dynasties of rulers, slaves, eunuchs, soldiers and trades people with particular skills. Authors have written about future totalitarian systems, where technology is used to produce insect-like societies that have controlled breeding from reproductive castes, and a zombie-like worker caste. The difficulty totalitarian regimes face is that they have to be long lasting to put such programmes into effect - much longer lived than the individual workers and despots. Lasting regimes occurred during the time of the Pharaohs, and may have ended with the Romans, although they continued in the Americas until destroyed by the Conquistadors.

 

Modern regimes do not seem to last that long. This does not mean that people do not still try to become Pharaohs, but modern communication and weapons usually soon lead to revolt - our DNA makes us all pursue our own selfish interests, and strive to become Pharaohs in our own area of control rather than remain a slave (thankfully most of us are not born into positions of power, and do not get much further than ordering the garden and shouting at the children). It seems that the more educated we become, and the more information we have access to, the less we are able to accept the slave role. It is clear that artificial organizations imposed on human society by accident or design must, if they are to succeed, take into account our DNA evolved social structure. This is effectively fixed in every one of us, and has arisen from millions of years of pre-historic evolution, like in the elephants. Our learning ability has meant that we can modify it, and tolerate undesirable structures, but the basic innate details need thousands of generations before they can be changed by natural selection. If we are going to have a successful transition to a global unit, intelligence will have to be used to fit the needs of our ape-like ancestry into the structure. This will have to be done in such as way that we, as individuals, hardly realise what has happened and can carry on our own little lives as if nothing had changed.

 

Sex and social structure

On the way back from Lake Bosumptwi we were lucky enough to see some vervets. These monkeys are seen over much of Africa, and can be quite a nuisance. Monkeys and apes always fascinate human beings, because we can see so much of ourselves in them. The difference between our DNA and that of a chimpanzee is miniscule. We watched the vervets gambolling around - the young playing, mothers looking after babies, teenagers squabbling over food, very like life in a normal human extended family group. Something was different, and stood out like flashing neon lights - it was the very obvious brilliant blue scrota of the dominant males. Visits to the monkey houses of zoos always arouse feelings of interest, fascination, or embarrassment about sex. Sexual activity seems to have an incredibly important role in the lives of apes and monkeys, well beyond anything seen in most other animals. Few would argue that we share this trait, even though we cover our sex organs with clothes. It is amusing to discuss how we got our rather distinctive anatomy, and how it fits into our natural social structure.

BABOON. What we see in the social structures and anatomy of monkeys and apes tells us a lot about the organization likely to have existed in our tribal ape ancestors. We may be fascinated or disgusted by the sexual goings on witnessed on a visit to the zoo, but that is what has brought us to where we are today.

Various attempts have been made to suggest the original social structure and behaviour of hominids. The most obvious signs of innate social structure can be found in our physical features, which are the visible results of long periods of natural selection and social practice. These include nakedness, the growth of a nose, hair colour change with age, baldness, size of testicles and penis, and the growth of exaggerated breasts and buttocks. Sexual relations are central to any social organization, and much can be deduced here by comparing mankind with other apes. Men who have gained despotic power usually take advantage of the situation to buy women or keep harems, but this is definitely not the primary human structure, otherwise men would have the vanishingly small testicles and penis of gorillas, and women would always know when they were ovulating. Nor did they organise into free-love societies such as chimpanzees, otherwise men would have enormous testicles and women would advertise their periods of ovulation.

 

Our testicle size tells us that we are more likely to be basically monogamous, but suffer the normal consequences intrinsic to dense co-habiting social groups. These are that when the male is out hunting or away on business, the female will take advantage of other males around to obtain more genetic diversity in her offspring. (Males do not have a monopoly on cheating on their partners.) This is a common feature in communally nesting birds, such as swallows, where females frequently mate with other males. DNA testing has also revealed that many other female birds, once held to be models of monogamy, are now known to regularly cheat on their partners. Ornithologists missed these clandestine forays, because the hen birds zip off before dawn for a quickie with another male. When females do this, sperm competition can take place, and from her point of view the chances of producing some strong offspring are improved. When it is a regular occurrence, the males are naturally selected to produce more sperm so that they are more likely to be responsible for fertilisation. That is why chimpanzees have such large testes.

 

Our testicles reflect this in being large enough to suggest that sperm competition was a significant factor in our evolution. Recent evidence shows that this has not changed in modern society, where DNA testing has found the uncomfortable statistic that somewhere between 10% and 30% of children are not by their putative fathers. The Crusaders were well aware of this and developed the chastity belt to protect their wives from being cuckolded. Wives in Java have also used such devices on their roving husbands. These inventions have been widely used in nature for millions of years. In rodents and damselflies semen forms a solid plug designed to foil mating attempts by other males. Animals with these adaptations rarely develop monogamous relationships. Some even have keys - penile extensions designed to dislodge plugs!

 

Sexual advertising is widespread in primates and its eye-catching nature is well known to our advertising industry. Exaggerated femininity is particularly well developed in chimpanzees, which advertise periods of ovulation by massive tumescence of the sexual organs. Human beings have enlarged breasts and buttocks, which are permanent features - an unusual development related to the fact that ovulation is concealed from both males and females. Concealed ovulation is usually thought to be part of the monogamous alternative to heightened sexual activity in a free-love society, because the male has to be sexually satisfied, even if copulation only occasionally coincides with ovulation, while the female needs to accept his attentions, as a trade-off for continued support in child-rearing. This is a typically human interpretation, which assumes that the human sexual drive is normal - it is not.

 

Our use of frequent and usually unproductive copulation as part of the bonding process is unusual to say the least. Other species are quite able to maintain lifelong marriages and long-term joint rearing of young without wasting time and energy on fruitless copulation. It could be that it is a way of exhausting the male partner so that he is less vigilant, particularly during the crucial time of ovulation. But more likely it is one of the first natural selection results of intelligence - selection for increasing levels of coital pleasure. This could be similar to other areas of sexual selection, such as exaggerated male plumage, but only available to intelligent beings.

 

Human penis

The size and structure of the human penis is another curiosity - it is unnecessarily large when compared to other apes and lacks a bone (baculum). The size appears to have no significance with regard to sperm competition, otherwise chimpanzees would be endowed with even larger organs. There must have been an advantage for early mankind to possess such an unnecessarily large organ - maybe it is another whim of female choice, a natural selection result of intelligence. (However, the extreme sex organs of many insects defy explanation, and the Argentine Lake Duck has a member extending more than the length of its body when erect - pretty impressive for a bird, when birds are not supposed to have a penis, according to the textbooks). Our relatively large penis could be part of the facio-genital mimicry commonly seen in apes, and part of the process of going down the pathway of developing insect-like social behaviour. The lack of hair suggests our ancestors lived in close co-habiting groups in a relatively controlled climate. Hair was no longer necessary and had the disadvantage of encouraging parasites (social animals living in fixed homes are usually plagued by external parasites). Hair-loss has also occurred in the mole-rat, which has developed a more highly evolved insect-like social caste system than our own.

 

Other primates commonly associate in large groups, especially chimpanzees and baboons where child minding is a shared occupation and division of labour is apparent. Sentinel and hunting jobs tend to go to males and food gathering and home occupations to females. It is interesting that in large groups, dominance-subordination relationships become important activities, particularly between males, where dominants need to continually exert their position. This is well known in baboons where males can be dangerously aggressive and subordinates engage in a range of ritual appeasement behaviours, which include presenting their backsides. It is a similar gesture to vanquished dogs rolling on their backs and presenting their most vulnerable parts. The dominant baboon responds in male-male situations by mounting the subordinate in a form of homosexual behaviour, it almost becomes a boring ritual, much like ants greeting one another on an ant trail. It is interesting that brightly coloured genitals are often used to advertise dominant status, like the blue vervet scrota. In the mandrill the mimicry is transferred to the buttocks, which are displayed when walking, making the animal appear to have a head at each end, instead of enhanced genitals - or is it a bum at each end?

 

Early man was almost certainly organised into extended family or tribal units like baboons or chimpanzees and our secondary sexual characteristics of beards, and the status markers of baldness and white hair, show that we have been structured in this way for a very long time. (Chimpanzees and gorillas have also inherited the use of white hair as an age or status marker, probably from our common ancestors). Male size and aggressive build in early human society can only have been a relatively minor factor in breeding success. Male gorillas and orang-utans are much larger and more aggressively adorned.