Ice age survival: clues in fossil DNA

摘要

Sur viving the last ice age was more than just a matter of growing a woolly coat. Rapid global temperature swings had to be matched by equally rapid adaptation. Now a remarkable find from Canada's permafrost could help explain how the trick was done, through a process that might offer organisms a way to cope with the dramatic climate change the world is facing.DNA extracted from the bones of an extinct bison shows that the environment influenced the way the animal's genes worked without altering the genetic code. It is the best evidence yet that such epigenetic changes can be fossilised.