Did mammels continue thier normal fur loss - fur gain cycle during the last ice age? When the continent cooled did animals adapt and keep thier winter coats for longer periods of time?
My gut tells me that more than just daylight is at work, intersting though.
i BELIEVE THAT WOULD BE CALLED EVOLUTION, SURVIVAL OF THE FITEST. stupid caps lock.. anyways, either those animals adapted, either through evolution with the genetic traits of the survivors being passed down or the animals migrated to the climate for which they were suited.
I have caught Alaska beavers, which live in Glacially fed rivers, with a summer temp near 37- 40 degrees, and in october they are still blue, december, and they have primed up. So environment is not a factor in the primeness. However, the traits or genetic disposition for them to have a heavier coat even in summer has evolved, the primeness is still dependant on the light.