evolution of the horse Essay -- essays papers

evolution of the cavalryFor many people, the horse family remains the classic causa of evolution. As more and more horse fossils have been found, some ideas about horseevolution have changed, but the horse family remains a good example ofevolution. In fact, we now have enough fossils of enough species in enoughgenera to examine details of evolutionary change.Evolution does not occur in a straight line toward a goal, like a ladder rather,evolution is like a forficate bush, with no predetermined goal. Horsespecies were constantly branching off the evolutionary tree and evolvingalong various unrelated routes. Theres no discernable straight line of horseevolution. Many horse species were usually present at the same time, withvarious numbers of toes, and adapted to various diets. In other words, horseevolution had no inherent direction. We further have the impression of straightline evolution because only one genus happens to still be alive, whichdeceives some people into thinki ng that the one genus was somehow the place of all the evolution. Instead, that one genus is merely the last survivingbranch of a once mighty and sprawling bush.Tracing a line of descent from genus Hyracotherium to Equus reveals severalapp arent trends reduction of toe number, increase in size of cheek teeth,lengthening of the face, and increase in body size. But these trends are notseen in all of the horse lines. On the whole, horses got larger, bu...