Page 187 - Deep Learning

170 Adaptation

call new Zealand. Wandering off in a different direction, the inuits and other
Eskimo nations survived by hunting from sealskin kayaks and building houses
out of snow. in this diversity of habitats, neither the ocean floor nor outer space
stand out as especially hostile or complicated, merely different.
The migration of humans into diverse environments happened in such
a short period of time that their genetic adaptations were limited to minor
variations in metabolism, skin color and body shape. Geneticists and anthro-
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pologists agree that there is a single human species. But the different environ-
ments placed different demands on those who wished to survive. to hunt the
north American buffalo with bow and arrow required different skills from
those needed to bring down a kangaroo with a boomerang. to build an igloo
required a different technique from that required to build a tree shelter in the
papua new Guinea rain forest. if the speed of colonization was too quick for
genetic change, people must have adapted to each new environment by learn-
ing rather than evolving the relevant skills and survival techniques.
This point is particularly well illustrated by cases in which a population
mastered a novel environment within a single generation. When the polynesian
ancestors of the contemporary Maoris arrived in new Zealand, they found an
environment that differed radically from a tropical island, the type of environ-
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ment from which they set out. Clubbing giant moa birds in the evergreen
high-altitude forests and spearing fur seals from open boats in the cold waters
off the coast of the South island bore little resemblance to food production
on a coral atoll with its jungle, lagoon and shoreline coconut trees. The old
food production skills must have been suppressed and new ones developed in
the course of a single generation – indeed, in the time it took the polynesian
settlers to consume what little foodstuffs remained on their sailing vessels
after the approximately 3,000 kilometer sea journey from the launching point
somewhere in Eastern polynesia.
The closure of the colonization process provides examples of even more
rapid mastery of novel environments. on September 6, 1962, off the coast of
Villefranche-sur-Mer, a Belgian diver by the name Robert Sténuit descended
60 meters to the bottom of the Mediterranean inside a 1 by 3.5 meter metal
cylinder designed, built and operated by the American aviator and under-
sea explorer Edwin Link. With support from the U.S. navy, Sténuit, who was
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breathing a helium-oxygen mixture to combat depth narcosis, was to stay on
the sea floor for two days, exiting the cylinder to perform submarine work in its
vicinity. due to accidents and bad weather, the experiment was cut short after
one day, but Sténuit was nevertheless the first person to spend 24 hours on the
bottom of the sea. only a few days later, on September 14, and a few kilometers