Arts, Books, History, Nature, Science

Book Review: The Origin of Language

LITERARY REVIEW

Intro: According to an evolutionary biologist, it takes a village to raise a child. And that’s why we started talking to each other

THE story of human evolution has undergone a distinct feminisation in recent decades. Or, rather, an equalisation: a much-needed rebalancing after 150 years during which, we were told, everything was driven by strutting and brawling males, with females tagging along for the ride. This reckoning has finally arrived at language.

The origins of our species’ exceptional communication skills constitute one of the more nebulous zones of the larger evolutionary narrative, because many of the bits of the human anatomy that allow us to communicate – notably the brain and the vocal tract – are soft and don’t fossilise. The linguistic societies of Paris and London even banned talk of evolution around 1870, and the subject only made a timid comeback about a century later. Plenty of theories have been thrown into the evidentiary void since then, mainly by men, but now evolutionary biologist Madeleine Beekman, of the University of Sydney, has turned her female gaze on the problem. Unlike a baby chimp that can cling to its mother, a human infant is entirely helpless for years.

Her theory, which she describes as having been hiding in plain sight, is compelling: language evolved in parallel with caring for our “underbaked” newborns, because looking after and caring for a helpless human baby on the danger-filled plains of the African savannah required more than one pair of hands (and feet). It needed a group among whom the tasks of food-gathering, childcare, and defence could be divided. A group means social life, which means communication. Social bonding meant language evolved to negotiate help, share information about infant safety, and for those bonds to be necessarily strengthened to keep “helpless” infants alive.

The evidence to support Beekman’s theory isn’t entirely lacking, but a lot of it is, as a matter of course, circumstantial. We know that the compromise that natural selection hit upon to balance the competing anatomical demands of bipedalism (walking upright and narrowing pelvises) and an ever-expanding brain was to have babies born early (before that brain and its bony casing were fully formed).

One of the discoveries of the newly feminised wave of evolutionary science has been that alloparents – individuals other than the biological parents who contribute parenting services – played a critical role in ensuring the survival of those half-developed human children. Another is that stone-age women hunted alongside men. In the past it was assumed that hunting bands were exclusively male, and one theory held that language arose to allow them to cooperate. But childcare was another chore that called for cooperation, probably also between genders, and over years, not just hours or days.

Fortuitously, the reconfiguration of the head and neck required to accommodate the ballooning brain had a side-effect of remoulding the throat, giving our ancestors more control and precision over their utterances. With the capacity to generate a large range of sounds came the ability to convey a large range of meanings. To begin with, this was useful for coordinating childcare, but as speech became more complex and sophisticated, alloparents – particularly grandmothers – used it to transmit their accumulated knowledge. This nurtured infants who were even better equipped to survive. The result of this positive feedback loop was Homo sapiens, the sole survivor of a once diverse lineage.

Regrettably, critics are likely to highlight that Beekman takes a very long time to get to this exciting idea. She does spend about half the book laying the groundwork, padding it out with superfluous vignettes as if she is worried the centre won’t hold. Once she gets there, she makes some thought-provoking observations. Full-blown language probably emerged about 100,000 years ago, she says, but only in our line – not in those of our closest relatives. “We may have made babies with Neanderthals and Denisovans,” she writes, “but I don’t think we had much to talk about.”

And whereas others have argued that language must have predated Homo sapiens, because without it the older species Homo erectus couldn’t have crossed the forbidding Wallace Line – the deep-water channel that separates Asia and Australasia – she draws on her deep knowledge of social insects to show that communication as relatively unsophisticated as that of bees or ants could have done the job. Having made a persuasive case for the role of alloparents in the evolution of language, Beekman concludes that we did ourselves a disservice when we shrank our basic unit of organisation down from the extended to the nuclear family. Perhaps, but historians including Peter Laslett have dated this important shift to the middle ages, long before the Industrial Revolution where she places it, and the damage isn’t obvious yet. Language is still being soaked up by young children, and is still a vehicle for intergenerational learning. It may take a village to raise a child, but as Beekman herself hints, a village can be constituted in different ways.

Beekman presents a radical shift in how we understand the birth of human speech. While traditional theories often credit hunting, toolmaking, or warfare as the primary drivers of complex communication, the author argues that the true catalyst was the inescapable need for cooperative childcare.

The Origin of Language: How We Learned to Speak and Why by Madeleine Beekman is published by Simon & Schuster, 320pp

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Nature, Research, Science

Arthritis gene linked to colonisation and spread of mankind

SCIENTIFIC RESEARCH

Arthritis Gene

The arthritis gene responsible for the painful condition which manifests itself in worn down joints is being linked to the process of natural selection and evolution of mankind.

A single gene that made it easier for early humans to colonise Europe and Asia also causes arthritis, researchers claim.

The gene, which is known to cause people to be more compact, became more common when early humans moved out of Africa.

Being smaller helped humans cope with colder temperatures because it meant less body area to keep warm.

However, the down side is that someone with the gene is twice as likely to develop arthritis as someone without it.

The findings highlight the role that genetics plays in the painful condition – which is often thought of as a disease caused by ‘wear and tear’ on joints.

Around a half of all European and Asian people carry the gene, which is ‘relatively rare’ in most Africans.

Researchers at Stanford University School of Medicine and Harvard University said the gene ‘has been repeatedly favoured [by natural selection] as early humans migrated out of Africa and into colder northern climates.’

Dr David Kingsley, professor of developmental biology at Stanford, said: ‘Even though it only increases each person’s risk by less than twofold, it’s likely responsible for millions of cases of arthritis around the globe.

‘This study highlights the intersection between evolution and medicine in really interesting ways, and could help researchers learn more about the molecular causes of arthritis.’

A more compact body structure due to shorter bones could have helped our ancestors better withstand frostbite and reduce the risk of fracturing bones in falls while slipping on ice, the researchers speculate.

These advantages in dealing with chilly temperatures and icy surfaces may have outweighed the threat of osteoarthritis, which usually starts to occur after prime reproductive age.

Dr Kingsley added: ‘The gene we are studying shows strong signatures of positive selection in many human populations.’

The research was first published in the online journal Nature Genetics. The gene, known as GDF5, was first linked to the growth of bones in the early 1990s.

Researchers found a variant that is very common in Europeans and Asians but also rare in Africans.


Science in motion

Science-in-motion: a series of short articles following topics in science.

. Genetic modification  

This refers to the use of modern biotechnology techniques to change the genes of an organism, altering the DNA that instructs its cells how to build proteins. Many crop plants are genetically engineered to possess desirable traits such as resistance to pests or harsh environments.

In traditional breeding of crops and livestock, farmers pick plants or animals with desirable traits and crossbreed them to create commercially valuable offspring. Genetic modification allows the traits of organisms to be altered in ways that are not possible through traditional breeding.

For example, some cotton plants are modified to carry a gene from soil bacteria. This makes them produce a chemical that kills insect pests, reducing the need for pesticides. Sometimes, genetic modification turns down or ‘silences’ the activity of genes that an organism already has. This can prevent oilseed rape crops producing unhealthy oils, for instance. Genetically modified animals are often used in experiments to study gene functions, but are not yet bred for commercial agriculture.

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