1 - Two "non Horses" creating a horse is not evolution....
Slow, gradual changes over time ...
2 - "Selection" - Think of a Polar bear , a half million yars ago or so there was probably a single bear like species that ended up evolving into both Polar bears & Grizzly Bears ... The Bears that were better adapted to snow & cold conditions (those with lighter/whiter coats to avoid being seen by prey/predetors, better swimming skills ect), were more likley to survive & therfore pass on their genes, eventually losing many of the genes/traits not needed, while a Grizzly in the forests needed darker coats to avoid being spotted, better tree climbing skills ect ... Add to this natural envirnmental selection the random mutations that are born/occur over time .. & we have our 2 bears today, while the orginal ancestor, less specialized for either envirnment, is now extict fossils...
The Ancestor of the horse are the evolutionary grandparents of today's Zebras, Donkies & horses ... These current animals evolved their traits due to adapting to their enviornment, & isolation from the other populations, along with a million years of births & mutations that occur. They can still interbreed, but are now so different that the offspring is sterile (mule) |