http://www.treehugger.com/climate-chang ... pgn=fbapl1
Climate scientists have painted a pretty grim outlook for our planet in the wake of an unabated release of greenhouse gases into the atmosphere -- from rising sea levels and increasing weather disasters, to resource shortages and mass extinctions -- but there's one side effect of global warming sure to make you go 'aww'. According to paleontologists, an early species of horse was discovered to have responded to an extended bout of unusually hot temperatures million years ago in the most peculiar of ways: by going miniature. And given the steamy future which may be in store, it could happen again -- this time, to your quite-possibly-mini great-great-grandkids.
For 175 thousand years, due to a rise in global temperatures 58 million years ago known as the Paleocene-Eocene Thermal Maximum, one of the first equestrian species to gallop the planet underwent a dramatic change in size. During this period, a higher than normal levels of atmospheric carbon dioxide lead to hotter planet, and in response fossil evidence of shows that an early ancestor of the horse, Sifrhippus, shrunk to the size of a house cat. Other species, say researchers, even halved in size to accomodate the hot spell.
In addition to this, many animals will probably die out or have their population significantly reduced.