Tool Use, Culture and Human Hubris
- Jeff Schweitzer
Scientist and former White House Senior Policy Analyst; Ph.D. in
Tool Use, Culture and Human Hubris
Posted: 02/04/2013 5:24 pm
Chimpanzees, our closest relatives, demonstrate something awfully
close to culture, once considered uniquely human. Chimps toy with
cultural evolution through tool use, also once regarded as exclusive
to our species. A study published on January 30, 2013, in the journal
PLOS ONE demonstrated how a cohort of chimps wise in the ways of
using a straw to suck juice out of a container can pass on that
knowledge by demonstrating the technique to naive chimps.
We humans have always thought of ourselves as particularly
intelligent, special, above all other animals. Religion tells us that
only we were made in the image of god. The son of god comes in the
form of a man, not chimp or weasel. We proudly note our compassion,
humor, altruism and impressive capacity to generate language,
mathematics, tools, art, and music. In citing this self-serving list
to bolster our claim to exalted status, filtered expediently to our
benefit, we assume that humans possess, and other animals utterly
lack, these honorable traits or capabilities. We ignore the
inconvenient fact that we choose to define and measure intelligence
in terms of our greatest strengths. We arbitrarily exclude from the
definition of intelligence higher brain functions in other animals.
We make bold claims of our uniqueness and divine status, only to find
over time that each claim ultimately fails as we advance our
understanding of animal intelligence and behavior. There is no better
example than tool use and culture. (All the examples below are from
numerous scientific journals and books, all of which can be found in
the bibliography in Chapter 3 of Beyond Cosmic Dice: Moral Life in a
Tool use at one point was indeed long considered solely the
providence of human ingenuity. But in fact non-human primates and
birds commonly use tools, mainly to gather food. Chimpanzees, for
example, regularly use stems as tools and can even pound stones with
purpose, although they have never mastered flint-making. Chimps also
use leaves as toilet paper. Egyptian vultures will search up to 50
yards for a rock to use to smash an ostrich egg. Green herons drop a
small object onto the surface of the water to attract fish, which are
fooled into thinking prey is nearby. The heron then turns the table
and makes a meal of the unsuspecting fish.
If an elephant is unable to reach some itching part of his body with
his trunk, the nearest tree often serves to relieve the problem. Just
as often, however, an itchy elephant will pick up a long stick and
give himself a good scratch with that instead. If one stick is
insufficiently long he will look for one better suited to the task.
With what appears to be clear intention, elephants have been observed
to throw or drop large rocks and logs on the live wires of electric
fences, either breaking the wire or loosening it such that it makes
contact with the earth, thus shorting out the fence. Elephants are
undoubtedly clueless about electron flow, but have mastered the use
of a tool to avoid its unpleasant consequences.
Some animals have graduated from tool use to tool fabrication. On the
Galapagos Island, one of the many finch species made famous by Darwin
uses a cactus spine as a spear to pry grubs from tree branches. Once
this woodpecker finch has procured his shish kabob, he holds the
skewer under foot to munch on the tasty snack. The bird will then
carry the spine to another tree looking for the next meal. This
finch, though, is not always happy with what nature provides, and
improves the cactus spine for its purpose. One finch was observed
shaping a forked spine into a single spike, and others shorten the
spine to just the right length for probing and holding. Some finches
can learn to use the tool by watching others do so.
These feats are noteworthy, but provide only examples of one animal
using one tool for one purpose. Even more impressive is the learned
use of a tool set. Chimpanzees in East and West Africa sequentially
use four tools to obtain honey, all gathered together for that
specific purpose. They start with a battering stick, then a use a
chisel-like stick, followed by a hard-pointed stick, finally ending
with a long slender flexible dip stick to pull out the honey. Each
tool is used in a specific sequence, and sometimes made to order by
clipping, peeling, stripping or splitting the wood to the desired
New Caledonian crows are famous for their ingenious tool fabrication,
both in the wild and in captivity. Betty, a female crow, was filmed
taking a piece of wire and trying to use it to grab some food at the
bottom of a narrow tube. After several unsuccessful attempts, she
removed the wire, fashioned a hook on the end, and subsequently used
her new weapon to grab the food with ease. In the wild, these crows
make an impressive variety of tools using a wide range of materials
for diverse purposes. These birds actually shape different hooks for
different tasks. This is tool use by any definition.
Until recently, the transmission of information through culture, or
socially learned tradition, was thought to be found only among
humans. Many considered this the "last stand" in proving human
uniqueness. Culture seems to be clearly a uniquely human invention.
In some human cultures, two people greeting each other will bow,
where in others the two will shake hands. Some kiss once or twice on
the cheek. Some societies prefer vodka over wine. Culture defines the
context of our lives.
But in the 1950s, a few brave researchers demonstrated that culture
was indeed found in other species, although this conclusion was
resisted for several decades.
On the small Japanese island of Koshima, researcher Kinji Imanishi
observed one day that a young female macaque named Imo took some
precious sweet potatoes that were inconveniently covered with sand to
a nearby stream to wash them off before eating them. That alone was
interesting because the behavior had never before been seen. But more
impressive, over time the entire colony adopted the innovation, and
their descendants wash their potatoes even today because mothers
continue to pass down the new tradition to the next generation.
Imo and her colony are not just an isolated example. In 1963, in the
Nagano Mountains of Japan, another young female macaque named
Mukubili waded into a hot spring to get some food that had been
thrown in the water. The warm water was apparently a delightful
respite from the bitter cold mountain air, and a few other young
monkeys climbed in. Much as in human cultures, at first the behavior
caught on only with the youth, but the old folks eventually got hip.
The behavior is now well established in the entire troop, and has
been passed on through many generations. In another example of
youth-driven culture, some juveniles learned to roll and throw
snowballs. That has no survival value, but is fun. The practice
spread to others in the troop and is now a common play behavior.
The indisputable conclusion that other species have culture, however,
is not the result of a few casual anecdotes or isolated case studies.
Instead, presence of culture in other animals is seen as the result
of carefully recorded observation by disparate scientists over many
decades. In 1999, a group of researchers got together to compare
notes from their years of field work with chimpanzees. Eventually
they documented 39 examples of behaviors present in one group of
chimps but not another, even when the groups lived in similar
environments and had access to the same foods and potential tools.
Cultural differences were seen in courting behavior, hunting
strategies, tool use, social grooming, medicinal plant use and
vocalizations. The behaviors were passed on from one generation to
the other within a social group, and not reinvented anew with each
generation. More recent work with orangutans has shown similar
examples of culture and social learning. The difference in behaviors
between groups was even more striking in orangutans, which interact
with neighboring groups less than chimpanzees.
In the final blow to the notion that culture is somehow uniquely
human, various forms of social learning within and between
generations have been demonstrated beyond primates, including in
birds, rats, elephants, whales (in addition to composing), and
perhaps even in fish.
Get Over Ourselves
In defining our uniqueness, we are using a bizarre circular logic,
working backward from a desired result. We look at all of our
capabilities as humans, and then declare that those very sets of
capabilities are what make us better than other animals, if not the
image of god himself. But even when we give ourselves a big handicap
by creating self-serving definitions that we know beforehand will
prove advantageous, the categories of "uniquely human" talents are
shrinking rapidly as we learn more about other animals and their
adaptive behaviors. Characteristics previously considered special to
our species have eventually been found, at least to some degree, and
often with some humor, elsewhere in the animal kingdom. We see in the
animal kingdom examples of impressive brain development,
intelligence, self-awareness, empathy, social organization, even some
ability in mathematics, as well as of course culture and tool use.
We are faced with the need to combat a fierce bias. People tend to
believe that our species is superior to and separate from the animal
kingdom, that we are the end point of the evolution of life on earth.
That notion is not only false but extraordinarily dangerous. It is
this hubris and arrogance that drives much of our most unsustainable
behaviors. If we are special we need not respect natural resources
put here by god for our use; nor must we protect animals we believe
to be our inferiors. Yet biological reality on the ground is quite
different from this species-centric view: human are nothing but a
normal consequence of natural selection, and certainly not the
pinnacle of evolution. We are nothing special, and bacteria are the
proof. We desperately look for traits only we possess, like tool use
and culture, only to be thwarted by animal ingenuity. It is time we
got over ourselves and adopted a more humble attitude about our role
in the biosphere. The chimps are watching as they sip their juice.
This Blogger's Books from Amazon
Beyond Cosmic Dice: Moral Life in a Random World
by Jeff Schweitzer, Giuseppe Notarbartolo-Di-Sciara
Few people are capable of expressing with equanimity opinions which
differ from the prejudices of their social environment. Most people
are even incapable of forming such opinions.
-- Albert Einstein