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81552
Snakes and the Ice Ages
Sometimes physical and environmental barriers team up to influence the distribution of snakes. In his book "The Snakes of Europe", British herpetologist J.W. Steward offers a concise explanation that Europe's paucity of snake species- less than three dozen, compared to more than 100 in the United States and 300 in Mexico- is largely a result of Pleistocene glaciation. He also explains how glaciation may have caused many species of European snakes- vipers, for instance- to split up into several subspecies.
At it's maximum, the ice extended as far south as northern Germany, European Russia, and England. South of the glacial margin tundra, cold grasslands and taiga, too chilly for snakes, stretched across Central Europe. Glaciers also expanded on the Alps and Pyrenees, sealing off southern Italy and Spain. Only in these two areas along with the Balkans did the climate remain moderate enough, because of Mediterranean's influence, to support deciduous forest- and snakes.
Glaciation decimated Europe's reptile species. Some species of snakes, although not many, found refuge in the Mediterranean enclaves. Cut off from each other in these refuges, members of the same species well may have differentiated into subspecies. After the last glaciation, some, although by no means all, of the refugees left their enclaves and spread out across Europe. The climate was warmer then than it is today so some species, such as the Aesculapian snake, penetrated far into the north. As temperatures dropped to a more typical level, this species retreated to Central and Southern Europe, where it lives today. Meanwhile, species more tolerant of cold, such as the adder, expanded their ranged due to limited competition.
Taken from the book "The Snake Almanac" by Edward R. Ricciuti
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You know she's a winner.
She couldn't be thinner.
Now she goes to the bathroom
to vomit up dinner.
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