Warm pockets during cold times and a rediscovered species
For the last 6 million years or so, the Earth has been subjected to drastic temperature fluctuations. During the Pliocene, the Earth underwent cycles of warm wet and cooler dry periods. Substantial continental ice began to form in the Northern Hemisphere around 3 million years ago (Mya), before the planet was plunged into a series of ice ages. Although you may think of an "ice age" as a snowy period after which woolly mammoths and neanderthals disappeared, you may not know that currently we are simply enjoying a "summer" break from this ice age. The last 2 millions years of Earth's history has consisted of various glacial periods interspersed by warmer times, known as interglacial periods.