32
2 The Genetic Context
east coast of Africa, with a probable stretch of 4,000 km without landfall to reach
Madagascar.
It is a remarkable fact that these selective adaptations occurred in a people living
not in the Arctic or in a high latitude but in Spice Islanders living on the equator.
Biological evolution in the region is tied to the Ice Age and post-glacial history of
Sundaland and Wallacea. Sundaland and Sahul were Ice Age refuges for people
coming from as far away as Africa and as long ago as 85,000 years. They were Ice
Age refuges too for countless species of plants and birds and animals, including
miniature elephants and numerous species of apes. They made possible the evolution of the amazingly colourful birds and butterflies and insects collected by the
naturalist Alfred Russel Wallace from 1854 to 1862. His observations in the Malay
archipelago of laws of natural biological evolution led to his perception of the principles governing evolution and so to his formulation of a theory of natural selection.
Hominid species dating back over half a million years and the newly discovered
but currently controversial Flores “hobbits” suggest too that Sundaland, and especially Wallacea, may have been an Ice Age refuge in earlier Ice Ages. The pressures
for selective adaptation can be seen in many of the Ice Age refugees. Both miniature elephants and even possibly miniature people (the “hobbits”) were adapting
through size reduction to survive on depauperate islands. Andamese women adapted
to limited food availability through developing the condition known as steatopygy
which enabled them to store remarkable quantities of fat in their buttocks as a food
supply against famine and as a food supplement during pregnancy and lactation.
Survival drives such adaptations. In the case of Spice Island mariners, ancestors of
the Polynesians, as for the cold-adapted Neanderthals in Europe, we suggest that
Nature took exposure to a long-standing continuous risk of hypothermia seriously.
With the Out of Taiwan hypothesis the supposed later Taiwanese ancestors of the
Lapita and Polynesian peoples could conceivably have “picked up” maritime skills
and technologies en route to the Bismarcks, on either an Express Train or a Slow
Train from Taiwan, but the evolution of a cold-adapted phenotype involves genetic
evolution through natural selection rather than cultural adaptation. Unless the Lapita
peoples were on an Express Train from the Arctic, the development in people living
on the equator of cold resistance greater than that of Inuit and Lapps suggests a very
long maritime history. A considerable time was needed for the requisite genetic
mutations and for the coalescence of these mutations, so that they were present in a
significant proportion of Spice Islanders before they set out to settle the Pacific.
2.6 Houghton’s Prehistory for the Proto-Polynesians
What selective pressures resulted in such an extreme measure of cold adaptation for
the ancestors of the Polynesians? Houghton’s answer was that these pressures were
geographical and occupational. He speaks of the selective pressures of particular
environments and argues that “the selective model predicts that genetic relationships
will follow geographic and local lines” [36].
2 The Genetic Context
east coast of Africa, with a probable stretch of 4,000 km without landfall to reach
Madagascar.
It is a remarkable fact that these selective adaptations occurred in a people living
not in the Arctic or in a high latitude but in Spice Islanders living on the equator.
Biological evolution in the region is tied to the Ice Age and post-glacial history of
Sundaland and Wallacea. Sundaland and Sahul were Ice Age refuges for people
coming from as far away as Africa and as long ago as 85,000 years. They were Ice
Age refuges too for countless species of plants and birds and animals, including
miniature elephants and numerous species of apes. They made possible the evolution of the amazingly colourful birds and butterflies and insects collected by the
naturalist Alfred Russel Wallace from 1854 to 1862. His observations in the Malay
archipelago of laws of natural biological evolution led to his perception of the principles governing evolution and so to his formulation of a theory of natural selection.
Hominid species dating back over half a million years and the newly discovered
but currently controversial Flores “hobbits” suggest too that Sundaland, and especially Wallacea, may have been an Ice Age refuge in earlier Ice Ages. The pressures
for selective adaptation can be seen in many of the Ice Age refugees. Both miniature elephants and even possibly miniature people (the “hobbits”) were adapting
through size reduction to survive on depauperate islands. Andamese women adapted
to limited food availability through developing the condition known as steatopygy
which enabled them to store remarkable quantities of fat in their buttocks as a food
supply against famine and as a food supplement during pregnancy and lactation.
Survival drives such adaptations. In the case of Spice Island mariners, ancestors of
the Polynesians, as for the cold-adapted Neanderthals in Europe, we suggest that
Nature took exposure to a long-standing continuous risk of hypothermia seriously.
With the Out of Taiwan hypothesis the supposed later Taiwanese ancestors of the
Lapita and Polynesian peoples could conceivably have “picked up” maritime skills
and technologies en route to the Bismarcks, on either an Express Train or a Slow
Train from Taiwan, but the evolution of a cold-adapted phenotype involves genetic
evolution through natural selection rather than cultural adaptation. Unless the Lapita
peoples were on an Express Train from the Arctic, the development in people living
on the equator of cold resistance greater than that of Inuit and Lapps suggests a very
long maritime history. A considerable time was needed for the requisite genetic
mutations and for the coalescence of these mutations, so that they were present in a
significant proportion of Spice Islanders before they set out to settle the Pacific.
2.6 Houghton’s Prehistory for the Proto-Polynesians
What selective pressures resulted in such an extreme measure of cold adaptation for
the ancestors of the Polynesians? Houghton’s answer was that these pressures were
geographical and occupational. He speaks of the selective pressures of particular
environments and argues that “the selective model predicts that genetic relationships
will follow geographic and local lines” [36].