'As far as
humans are concerned, language has got to be the ultimate evolutionary
innovation. It is central to most of what makes us special, from consciousness,
empathy and mental time travel to symbolism, spirituality to morality (Kate Douglas 2005).
'Somewhere in
the last 100,000 years or so, human beings hit upon language. Human language
must have seemed an odd-sounding innovation to the other animals around. But by
allowing the expression of arbitrarily complicated concepts, human language
allowed people to process information in a highly distributed fashion. The
distributed nature of human information processing in turn allowed people to
cooperate in new ways, forming groups, associations, societies, companies, and
so on. Some of these new forms of cooperation proved strikingly effective, as
various forms of distributed information processing, such as democracy,
communism, capitalism, religion, and science, took on a life of their own,
propagating themselves and evolving over time. It is the richness and
complexity of our shared information processing that has brought us this far (Seth Lloyd, Programming the Universe).
Let us
continue from where we left off in the previous post (Part 112). Deacon (1997) traces the evolution of social complexity by
assuming that the early humans were dual-parenting. Since their sense of smell
was not very acute (thus ruling out a role for chemical signalling through
pheromones), some other type of sexual signalling evolved between the male and
the female. This is how social
communication originated and evolved as a kind of social hormone.
Other than
sex, availability of food is the major factor determining the survival of a
species. Males had to cooperate with one another for hunting. Deacon again:
‘Males must hunt cooperatively; females cannot hunt because of their ongoing
reproductive burdens; and yet hunted meat must get to those females least able
to gain access to it directly (those with young), if it is to be a critical
subsistence food. It must come from males … [who] … must maintain constant
pair-bonding relationships’.
This need for
hunting in groups resulted in the evolution of a social structure implying a
symbolizational solution to the problem of survival. This is because symbolic
reference, as also speaking and thinking, are basically of a social nature.
There was naturally a concomitant evolution of the speech organ (voice box).
Grooming
According to
Robin Dunbar: ‘One of the
most important ways that primate allies show their affection to each other is
by grooming. Grooming not only gets rid of lice and other skin parasites, but
it also is soothing. Primates turn grooming into a social currency that they
can use to buy the favour of other primates. But grooming takes a lot of time,
and the larger the group size, the more time primates spend grooming one
another. Gelada baboons, for example, live on the savannas of Ethiopia in
groups that average 110, and they have to spend twenty percent of their day
grooming one another. … If we had to bond our groups of 150 the way primates
do, by grooming alone, we would have to spend about 40 to 45 percent of our
total daytime in grooming’.
The primates
in the savannas also had to find food, and therefore such a large investment of
time in grooming would have caused a non-sustainable work vs. life
balance. Language emerged as a better way
of bonding.
Evolution of
word-speaking species
Humans began
with sound language, gradually increasing the vocabulary. But there is a severe
limit to how many sound calls you can have which still sound distinct. The next
step in the evolution of language was a stringing together of sounds into
specific sequences, namely words. Word-speaking
species naturally had an evolutionary advantage.
Sentences
syntaxing words were the next level of evolving complexity. Brain size
increased concomitantly to understand and remember words, syntax, grammar, and
sentences (Zimmer 2006): ‘A
syntax-free language beats out syntax when there are only a few events that
have to be described. But above a certain threshold of complexity, syntax
became more successful. When a lot of things are happening, and a lot of people
or animals are involved, speaking in sentences wins … Something about the life
of our ancestors became complex and created a demand for a complex way in which
they could express themselves … A strong candidate for that complexity, as
Dunbar and others have shown, was the evolving social life of hominids’.
This social
evolution of complexity is the advantage humans have over other animals. They
have the capacity to introduce and expand complexity in social life, and
development of language is both a cause and an effect of this capacity. As Kate Douglas (2005) said, ‘In
a sense, language is the last word in biological evolution. That’s because this
particular evolutionary innovation allows those who possess it to move beyond
the realms of the purely biological. With language, our ancestors were able to
create their own environment – we now call it culture – and adapt to it without
the need for genetic changes’.
Whereas humans
and chimpanzees have many genes in common, the expression of certain genes is more common in the human brain.
Moreover, the brains of newborn humans are far less developed than those of
newborn chimpanzees, and the neural networks of human babies are developed over
many years of exposure to a linguistic
environment. Through a continuous process of unsupervised learning
(experimentation), supervised learning (from parents, teachers, etc.), and
reinforced learning (the hard-knocks of life, and rewards for certain kinds of
action), the child’s brain performs evolutionary computation.
With language
came the possibility of emergence of ‘memes’. Language coevolved with memes.
Next time.
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