“Here we
argue that humans may be smarter than other creatures, but none of us is nearly
smart enough to acquire all of the information necessary to survive in any
single habitat… We owe our success to our uniquely developed ability to learn
from others. This capacity enables humans to gradually accumulate information
across generations and develop well-adapted tools, beliefs, and practices that
are too complex for any single individual to invent during their lifetime.”
Contrast
the need for social learning with the EP hypothesis that humans are simply
smarter than other species, have more flexible cognition, and thus are adapted
to the “cognitive niche.” The ability to learn socially merely augments these
capacities.
“The cognitive niche hypothesis overestimates the extent to which
individual human cognitive abilities allow people to succeed in diverse
environments and misunderstands the role that culture plays in a number of
important ways. We suggest, instead, that our uniquely developed ability to
learn from others is absolutely crucial for human ecological success…We have
entered the “cultural niche,” and our exploitation of this niche has had a
profound impact on the trajectory of human evolution.”
There are so many local adaptations learned and transmitted for
surviving, especially in harsh conditions (which are most places, really). It seems unlikely that an individual could
survive on one’s own, or even a group of individuals learning socially could
master an environment quickly.
The “lost European explorer experiment” – explorers get lost and either
die or are saved by indigenous people.
Loss of beneficial technologies after isolation and diminished population
size (Tasmania). Also occurred in other islands. Also a good example of Polar Inuit losing and
then regaining technologies. Kind of amazing. Really telling, among other
things, is that the Polar Inuit remembers tools like leisters (pronged spear
for catching fish) and bows and arrows, but did not know how to make them and
could not figure it out.
-------------------------
Ev Psych people often talk about the benefit of social learning as
outsourcing the cost of individual learning – see quote by Barrett et al.
However, Rogers (1988) makes clear that this logic is fallacious. If the only
benefit of social learning is to avoid the costs of individual learning, social
learning can invade but does not increase the fitness of the population.
---------------------------
“If imitators are simply information scroungers, then they will spread
until selection no longer favors imitation.”
Instead, “cultural learning can increase average fitness only if it
increases the ability of the population to create adaptive information.” Three
ways for this to happen:
1.
Cultural learning allows individuals to learn selectively – learn from
others only when environmental cues provide no guidance.
2.
Cultural learning allows gradual accumulation of small improvements, and
if these are cheaper than big improvements, cultural learning can reduce the
population’s learning costs.
3.
By comparing “teachers” and learning selectively from successful
individuals, “pupils” can acquire adaptive information without turning to
environmental cues.
a.
If individuals recombine information from multiple teachers, the can
create complex cultural adaptations without any intelligence, save that
required to distinguish among more or less successful teachers.
P. 5: “…As a result, we interpret this logic as predicting that
selection should have favored a psychology that causes individuals to rely
heavily on cultural learning.”
Possibly the crux of the argument:
“Organisms that cannot imitate must start with whatever initial guess is
provided by their genotype. Over their lifetimes, they can learn and improve
their bow. However, when they die these improvements disappear with them, and
their offspring must begin again at the genetically inherited initial guess. In
contrast, cultural species can learn how to make bows from others after these
have been improved by experience. Therefore,
cultural learners start their search closer to the best design than pure
individual learners and can invest in further improvements. Then, they can
transmit those improvements to the
grandkids, and so on down through the generations until quite sophisticated
artifacts evolve.”
On copying irrelevant traits –it doesn’t matter as long as there is a
correlation between a suite of traits and results. See the example of bow form
copying. Also see the developmental literature, some of which is cited here.
“These models predict that an adaptive evolved psychology will often
cause individuals to acquire the behaviors they observe used by in others even
though inferences based on environmental cues suggest that alternative
behaviors would be better.” This reminds me also of the persistence of
maladaptive cultural behaviors in new environments, for instance, the European
settlers in Greenland in Diamond’s Collapse. The prestigious individuals were
the cultural founders, not the savage Inuit, so the latter weren’t imitated.
The first paragraph of “Evidence for Cultural Adaptation” has a really
good contrast of the cognitive niche hypothesis and the cultural niche
hypothesis. Most crucially, the latter predicts that innovations will be
adopted without the individuals understanding how they are adaptive or why
certain details are included in a design. This
is the crux of CCE as distributed computation. An example is the experiment with children
and chimps and the puzzle box.
