Natural selection

Buddhist Biology from Barash

chap3

Illustration by Andy Gammon

Review of David P Barash, Buddhist Biology: Ancient Eastern Wisdom Meets Modern Western Science (Oxford University Press, New York, 2014). By Ratnaprabha.

Through the nineteenth century, Western science gradually disengaged itself from Christian religion, and scientists set themselves up as rivals to churchmen in interpreting the world. Nevertheless, religion remains a force in our culture, and some scientists detect a spiritual vacuum in their own hearts, turning back in hope towards religious traditions, at least for their own personal solace. Yet to answer one set of needs through a religious allegiance, and a separate set of needs through the discipline of science leaves a frustrating split, despite Stephen Jay Gould’s recommendation that the two should be confined to “non-overlapping magisteria”.[1] David Barash joins the club of those scientists wanting science and religion to be at least on speaking terms with each other, better still to marry.  His arranged bride for science is Buddhism.

Thus he proposes a “Science Sutra… [in which] not-self, impermanence, and interconnectedness are built into the very structure of the world, and all living things — including human beings — are no exception.… It can help animate — more precisely, humanise — this otherwise cold and dreadful skeleton of rattling bones”. (Pages 27-8. The image of science as a rattling skeleton is from Bertrand Russell.)

Barash is a psychology professor at the University of Washington who has been active in the field of peace studies, but by training he is an evolutionary biologist, and it is biology in particular that he wishes to give a Buddhist flavour. He is an avuncular and jaunty writer, and this being his 33rd book, you can see that his publishers give him some leeway. He admits that they wanted him to discard altogether a chapter that tries to add existentialism to the mix, and they’ve left him to his own devices to the extent that the Buddhist sections are riddled with, mainly minor, errors of fact and spelling. As for science, he discusses genetics, ecology and neuroscience as well as evolution, and he is on pretty firm ground here, though some mistakes do creep in – including the howler that Newton discovered the second law of thermodynamics (page 58).

An enthusiastic Buddhist for most of his life, Barash’s chief inspiration is the Vietnamese Zen teacher Thich Nhat Hanh. Thus, along with impermanence and non-self, the main Buddhist concept he wishes to apply to his biology is interconnectedness, all things linked in a dance of mutual dependence, a teaching that Thich Nhat Hanh adapts for modern audiences from Chinese Hua Yen Buddhism. Ecology, too, demonstrates that organisms and their environments constitute a net of mutual dependence.

Buddhist teachings argue that anything which depends for its state on external factors must change when those conditioning factors change (anitya), and if no part of that thing is immune from dependencies, then to identify any essential protected nucleus of self must be mistaken (anatman). In biology, impermanence is the rule, and evolution superimposes long-term inter-generational changes on the short-term developments undergone by every organism, so that only the genes themselves are (according to Barash) comparatively stable. My impression here is that Barash’s popular writing has not yet caught up with advances in genetics that he must surely be aware of. The gene as an almost fixed sequence of bases in DNA that codes for some detectable feature of an organism is only one component of inheritance. Genes interact in complex ways determined partly by environmental influences, events can switch genes on and off according to circumstances, and survival-enhancing features innovated by a parent can pass to its descendants without changes to the genetic sequence. As I was reading the book, there was news of research showing that mice taught to become frightened when they smelt cherry blossom could pass that fear to offspring they had no contact with: the genetic basis of the offsprings’ smell receptors had changed as a result of their parents’ experience.[2] A process like this is termed epigenetic, and epigenetics increasingly seems to be a significant factor in evolution.

In highlighting anitya and anatman (just two of the traditional three marks), and then adding interdependence, Barash is already reframing Buddhism according to his own preferences. As well as downgrading the third mark (duhkha, suffering), he adds pratitya samutpada, which is indeed basic to a Buddhist understanding of human experience, though it is incorrect either to translate it or to sum it up as only interdependence. It refers to an understanding of how the apparent entities that we single out from our experience come into being and pass away, as well as how they relate with other entities in the present moment. (The Present Moment, incidentally, is the name of Barash’s campervan, named so that he can sometimes claim to be “in” it.)

Barash is happy to modify traditional Buddhist teachings, if the results serve the needs of his audience: modern Westerners who have confidence in the findings of science. Thus he would ditch many of the practices of Eastern Buddhists (he rather condescendingly views them as naive and superstitious), and many of the teachings of what he calls “originalist” Buddhism. Someone has drawn his attention to David McMahan’s The Making of Buddhist Modernism, and since it is effectiveness and accuracy that motivate him, he is more than happy to confess that his grasp of Buddhism has come largely from the interpretations and revisions of westernised Buddhists. In fact he goes further, seeking to delineate what almost amounts to his own new religion, which he calls Existential Bio-Buddhism.

I think that this is fine, and it is very gratifying to see a popular scientist sharing an enthusiasm for Buddhism with his readers. Those whose interest is piqued can track down teachers and writers with a stronger basis in Buddhist traditions, and a deeper experience of practising them. But it is disappointing that he lacks the curiosity to further explore the aspects of Buddhism he is tempted to dismiss. (The “arrant nonsense” (page 11) of rebirth, for example, he explains as a “silliness about [transmigration of] souls” (page 138), and concludes that Buddhism must be “muddled” to teach both rebirth and anatman.)  One day, through a more daring dialogue than Barash risks, the interpenetration of Buddhism and biology is going to yield exciting fruit.

How is his biology informed by Buddhism? He uses it to speed up the defeat of essentialist and Platonic ideas in biology, and to support engagement with environmental issues, with its visions of interconnectedness and non-violence. Evolution confirms a kinship between humans and animals, hence a sense of solidarity with other forms of life, and a valuing of the natural world around us. Evolution and Buddhism also similarly agree that human beings are not special, indeed none of us as an individual ego is special either. In return, Barash is happy to contribute a conventional critique of Buddhism from a materialist scientific standpoint.

What other fruit could the dialogue yield?  What interests me most is the mind as an evolved phenomenon. From a human point of view, which is the only viewpoint we have access to, the degree and scope of our awareness is unparalleled in the natural world. Somehow we have come to the ability to reflect on our own experience, sometimes holding the stream of our consciousness in the illumination of mindful awareness. And we can enhance our level of consciousness through working on the mind with the mind. Perhaps as a consequence of this reflexivity, we seem largely trapped in a sense of separation from the world, a subjective me peering out at its hostile or alluring surroundings, always other. The teaching of pratitya samutpada states that this consciousness is dependently arisen, i.e. we can come to comprehend the evolutionary processes which gave rise to human consciousness, and thus understand our own minds better.

I feel that this understanding will not be well served by insisting on a materialist standpoint, as Barash and most scientists of standing do at present. Materialism seems to me to be primarily the rotting corpse of an old European debate, a debate that concluded first that mind and matter were two entirely distinct substances, and later that matter was the one real substance that made up everything in the universe, so that mind is nothing but patterns of electrical and chemical processes in the brain. The three truths that Barash imports from Buddhism – impermanence, not self, and pratitya samutpada – undermine such strict bifurcations as that between mind and matter. And I would say that honest reflection on experience doesn’t allow one to agree that awareness is illusory.  Like the objective world, the subjective or “inside” pole of experience must have arisen through law-governed causal sequences that can be understood. This is true of the whole range of minds found amongst animals, human and nonhuman, as well as this particular fleeting event of awareness that is my present moment. Buddhism wants to find evolutionary explanations (using the term ‘evolution’ in a general sense, not just as Darwinian natural selection). Buddhism has an evolutionary vision, as does biology. Biology is particularly interested in the evolutionary history of consciousness, Buddhism teaches its evolutionary potential, the further development of consciousness through contemplative methods.

Once mind or awareness is taken seriously as a genuine (though not substantial) phenomenon, we could consider its importance in the lives of animals as well as humans. It has arisen through evolution by natural selection: did its presence have any effects on the process of evolution? (Recall interdependence.) One possibility is through the Baldwin Effect, whereby innovative behaviours by animals (and behaviours have a mental origin) can propel them into new environmental niches where fresh selection pressures apply. For example, the Galapagos finches which now instinctively use cactus thorns to extract larvae from tree branches could not have started with a mutation for the behaviour – it is far too complex – they must have started with the novel behaviour, then passed it on through learning, until its different components were gradually selected for in the genes.[3]

Then there is the last of the three marks, duhkha or suffering. Entrenched views don’t just inhibit scientific progress, they may also inhibit compassion, and even promote antisocial practices in science, from cruelty to animals to environmental destruction and involvement in the technology of warfare. I think that an acceptable ethical framework, to be discussed and adopted by scientific communities, has its most likely origin in Buddhist ethics, a natural ethics based in intention and the consequences of behaviour rather than in scriptural commandments. Currently, scientists tend to govern their work with one eye on the law and the other on public opinion, but with little genuinely humanitarian ethical guidance.

Barash gives the impression of being an ethical man, and perhaps in a future work he will attempt to apply Buddhist ethics to his science. It may be for others to investigate how a fresh view of mental processes and their role in evolution, stimulated by Buddhism, could open up new avenues of research, as well as more creative ways of interpreting experimental results. More generally, Buddhism suggests a very open and provisional approach to concepts such as the gene, the species, and the individual organism. Constant reminders of impermanence, not self, and pratitya samutpada could release the creativity of scientists when they are entrenched in the “normal science” stage of struggling to fit research results into outdated theories, unwilling to let go of time-honoured biological concepts.

I would recommend Buddhist Biology to readers whose main allegiance is with science. It provides a friendly and engaging tourist guide to some of the features of Buddhism. We natives may chuckle at the guide’s simplifications and inaccuracies, but he points out impermanence, not self and interconnectedness; he shows how they apply to the biological sciences; and so he gives an authentic impression of Buddhism that may lead some of his readers to investigate it more thoroughly elsewhere, and to explore its practices in their own lives.

[1] Stephen Jay Gould, “Nonoverlapping Magisteria,” Natural History 106 (March 1997): 16-22.

[2] http://www.nature.com/neuro/journal/v17/n1/full/nn.3594.html accessed 1/1/14.

[3] D Papineau, “Social learning and the Baldwin effect” In A. Zilhão (ed.), Cognition, Evolution, and Rationality. (Routledge, 2005).  Also see Erika Crispo, “The Baldwin Effect and Genetic Assimilation” in Evolution 61-11: 2469–2479 (2007).

Have animal minds directed evolution?

chap4Mind in Evolution

From The Evolving Mind, Chapters 3 and 4.

We can be very confident that our earth has supported a continuous process of the evolution of the structure of living organisms. More tentatively, we can also trace how the ‘internal’ dimensions of animals – their minds – have evolved. It is fairly clear that the capacity of animals’ minds has been limited by the size, complexity, and degree of centralization of their nervous systems, so that the evolution of physical form has constrained the evolution of mind. But has the feedback worked in the other direction too? Did mind play an active role in evolution, or was the human mind just ‘an accidental afterthought in a quirky evolutionary play’, as the biologist S.J. Gould puts it?[i]

Natural selection leads to increasing adaptation to a specific environment; it tends to promote specialization. In the mind, specialization is served by very specific inborn habits and instincts, which evolve by natural selection. But mind has an element which works in the opposite direction, particularly if individual learning and cultural traditions are possible: mind can be flexible. It can adapt an animal by coming up with behaviours that suit unexpected circumstances.

Because of its great adaptability, it turns out that mind has indeed been active in evolution. In particular, through behaviour, it can influence the process of natural selection itself. Apparently, behaviour can direct selection.

Behaviour-led Selection: An Example

General behaviour-led selection process

General behaviour-led selection process

Here is a plausible example of how animals’ behaviour can direct the evolutionary line their species follows.[ii] As always in biological evolution, change is very slow, or if there are fast changes, they are very rare. This means that complete examples of behaviour-led selection have not been observed occurring in nature. In addition, fossil evidence for behaviour as opposed to structure is very hard to come by. So my example is of what may have happened, not of something that definitely did happen.

The only mammals that survived the dominance of the dinosaurs were little shrew-like creatures, probably living in the undergrowth of woods and forests, and feeding by night on small animals such as insects. They had smallish brains and used their noses rather than their eyes to sense their surroundings. By 80mya, some of these insectivores had taken to the trees, giving rise to the order of primates, mammals such as monkeys, apes, and humans. Some of the earliest fossil primates were rather like bushbabies with buck-teeth, having big, forward-facing eyes, and large brains. How did the change in habitat and structure come about?

Imagine a particularly fearless early mammal running up a low branch one night. Perhaps it is being pursued by a predator; perhaps it is in pursuit of a large and juicy beetle; or perhaps it feels a vague stirring of curiosity. It finds up the branch a snug hole, and spends the dangerous daylight hours asleep there. It is safer from predators, flooding, and other dangers than its relatives, who still hide by day in burrows, under rocks, or in piles of leaves. So it teaches its own young to sleep a little above ground level. Perhaps other members of the same species imitate it, or discover the new behaviour for themselves.

Because of the extra safety, individuals with the new behaviour survive better and leave more offspring (which follow the new tradition) than conservative individuals, and scrambling into low branches every morning becomes the norm throughout the population, probably within a few dozen generations. What is more, the pioneering behaviour has opened up a new ecological niche for the species – the trees. Trees offer safer nesting holes, and also a new range of insect foods; perhaps berries and fruits, too. Our pioneering insectivore may be tempted to spend the whole time in the new habitat.

A change of environment, a new ecological niche, means new selection pressures, and this is where the conventional evolutionary mechanisms come into play. The animals are spending time in trees. However, they are not adapted for climbing but for scampering about in the leaf litter. Any mutations will be strongly selected for if they tend to develop hands that can grasp the branches, a bushy tail for balance when jumping, good binocular vision for safe climbing and finding food, and so on. So first we had a behavioural change which introduced the animal into a new environment, and then naturally selected inherited variations changed the animal’s structure. Even before the change of structure, incidentally, the new climbing behaviour could become an innate, inherited behaviour rather than one that has to be learnt afresh by each baby mammal. Natural selection sometimes ‘prefers’ instinctive to learnt behaviours, because they can be carried out more quickly and automatically, freeing the attention for other tasks.[iii], [iv]

Behaviour and Niche Change

The example of ancient insectivores discovering life in the trees showed how innovations in behaviour can open up a new environmental niche. The finding of new niches has been a vital part of animal evolution. Evolution requires not just natural selection but also a change in niche, and behaviour-led selection can be involved in niche change. If the environment alters, or if some individuals stray into a new environment, behavioural changes are very likely to play a role in helping them to survive. For example, if our primitive insectivores were plunged into a series of severe winters, behavioural innovations in making cosier nests might well prevent the extinction of the population for long enough for thicker and thicker fur to arise by the natural selection of inherited variations in fur length.

The potential for new behaviours is also, presumably, often important when an animal is faced with changes in local habitat and geography, food supply, predators, or competitors. If the insectivore lives mainly on slugs but the slugs die out, it must turn to another food or starve to death. (We must not forget here an even more direct way in which animal choice influences evolution. That is the selection of a preferred mate, whose genes will mix with the suitor’s genes to contribute to the next generation.)

New species are thought to arise usually by the splitting of an existing species, so we need some mechanism which isolates the population from any remaining members of the species still following the old life-style, so that the new and old groups do not interbreed. Some isolation mechanisms themselves involve changes in behaviour, so that behaviour-led isolation should be added to behaviour-led selection as a factor in evolution.

For evolution to proceed, reproductive isolation and niche change must occur together. In animals that can change their behaviour, new behaviours are likely to be the commonest way for that to come about. As the biologist C.H. Waddington observed:

Animals … live in a highly heterogeneous ‘ambience’, from which they themselves select the particular habitat in which their life will be passed. Thus the animal by its behaviour contributes in a most important way to determining the nature and intensity of selection pressures which will be exerted on it.[v]

It is through behaviour-led selection that animals may affect the future course of the evolution of their own species. Individual choices and preferences ensure that evolution does more than merely grope randomly into new areas. By way of recapitulation, here is how the philosopher Karl Popper summarizes this view:

At first sight Darwinism … does not seem to attribute any evolutionary effect to the adaptive behavioural innovations of the individual organism. This impression, however, is superficial. Every behavioural innovation by the individual organism changes the relation between that organism and its environment: it amounts to the adoption of or even to the creation by the organism of a new ecological niche. But a new ecological niche means a new set of selection pressures, selecting for the chosen niche. Thus the organism, by its actions and preferences, partly selects the selection pressures which will act upon it and its descendants. Thus it may actively influence the course which evolution will adopt. The adoption of a new way of acting … is like breaking a new evolutionary path.[vi]

[i] Gould, S.J., Wonderful Life, Penguin, Harmondsworth 1991, 233.

[ii] A similar example was given by H.W. Conn in 1900, quoted in Hardy, A., The Living Stream, Collins 1965, 179.

[iii] Reid, R.G.B., Evolutionary Theory: The Unfinished Synthesis, Croom Helm 1985, 244; Bateson, P., ‘The Active Role of Behaviour in Evolution’ in M.-W. Ho and S.W. Fox, Evolutionary Processes and Metaphors, 191–207, Wiley 1988, p6 of preprint. But John Maynard Smith (‘The Birth of Sociobiology’, in New Scientist 26 September 1985, 50) doubts that the behaviours themselves would become genetically fixed.

[iv] Behaviour-led selection is a specific form of the ‘organic selection’ independently proposed by C. Lloyd Morgan in Britain and J. Mark Baldwin and H.F. Osborne in America. The history and status of the idea of organic selection is reviewed by R G B Reid, Evolutionary Theory, (Croom Helm 1985, 239–247). It is also discussed by (among others) the following biologists: Julian Huxley (Evolution, the Modern Synthesis, Allen & Unwin 1942, 523), G. Simpson (‘The Baldwin Effect’, in Evolution, vol 7 (1953), 110–117), E. Mayr (Animal Species and Evolution, Harvard University Press 1963, 95, 106–7, 604–5), A. Hardy (The Living Stream, op cit, 154–5, 162–207. Hardy gives a number of other references to writing on organic selection in The Living Stream and Darwin and the Spirit of Man (Collins 1984)), C.H. Waddington (The Evolution of an Evolutionist, University Press, Edinburgh 1975, 89, 279–281), J. Piaget (Behaviour and Evolution, Routledge & Kegan Paul 1979 (1st edn 1976), xiv–xv, 15–45, 134–145), Patrick Bateson, (‘The Active Role of Behaviour in Evolution’, in M.-W. Ho and S.W. Fox, op cit, 191–207). The philosopher of science Karl Popper is an enthusiastic proponent of behaviour-led selection as the source of direction in evolution. (Objective Knowledge, Clarendon, Oxford 1972, Chapter 7, and Unended Quest, Collins 1976, 173–80.) Interestingly, standard university textbooks on biology or evolution rarely mention organic selection or the Baldwin Effect (as it is also known), and negligible experimental work has been done on its behavioural aspect.

[v] Waddington, ‘Evolutionary Systems, Animal and Human’, in Nature, vol 183, 1634–8. Waddington included the selection of niches by behaviour in his ‘exploitive system’ (‘Evolutionary Adaptation’, S. Tax (ed), The Evolution of Life (Chicago 1960)).

[vi] Popper, Unended Quest, op cit, 180 (Popper’s emphasis).