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Evolution of the Horse
The evolution of the horse involves the gradual development of the modern horse from the fox-sized, forest-dwelling Hyracotherium. Paleozoologists have been able to piece together a more complete picture of the modern horse's evolutionary lineage than that of any other animal. The horse belongs to an order known as the Perissodactyls, or "odd-toed ungulates," which all share hoofed feet and an odd number of toes on each foot, as well as mobile upper lips and a similar tooth structure. This means that they share a common ancestry with tapirs and rhinoceros. The Perissodactyls originally arose in the late Paleocene, less than 10 million years after the extinction of the dinosaurs. This group of animals appears to have been originally specialized for life in tropical forests, but whereas tapirs and, to some extent, rhinoceroses, retained their jungle specializations, horses instead adapted to life on dryer land in the much-harsher climatic conditions of the steppes. The early ancestors of the modern horse walked on several spread-out toes, an accommodation to life spent walking on the soft, moist grounds of primeval forests. As grass species began to appear and flourish, the equids' diets shifted from foliage to grasses, leading to larger and more durable teeth. At the same time, as the steppes began to appear, the horse's predecessors needed to be capable of greater speeds in order to outrun predators. This was attained through the lengthening of limbs and the lifting of some toes from the ground in such a way that the weight of the body was gradually placed on one of the longest toes, the third... MORE
Horse Evolution Over 55 Million Years
How can you explain the sequence of horse fossils? Even if you insist on ignoring the transitional fossils (many of which have been found), again, how can the unmistakable sequence of these fossils be explained? Did God create Hyracotherium, then kill off Hyracotherium and create some Hyracotherium-Orohippus intermediates, then kill off the intermediates and create Orohippus, then kill off Orohippus and create Epihippus, then allow Epihippus to "microevolve" into Duchesnehippus, then kill off Duchesnehippus and create Mesohippus, then create some Mesohippus-Miohippus intermediates, then create Miohippus, then kill off Mesohippus, etc.....each species coincidentally similar to the species that came just before and came just after? Creationism utterly fails to explain the sequence of known horse fossils from the last 50 million years. That is, without invoking the "God Created Everything To Look Just Like Evolution Happened" Theory. [And there is other evidence for evolution that is totally independent of the fossil record — developmental biology, comparative DNA & protein studies, morphological analyses, biogeography, etc. The fossil record, horses included, is only a small part of the story.] Creationists are thus forced into illogical, unjustified attacks of fossil dating methods, or irrelevant and usually flat-out wrong proclamations about a supposed "lack" of "transitional forms"... MORE
Horse Evolution by Kathleen Hunt
Our familiar Equus is merely one twig on a once-flourishing bush of equine species. We only have the illusion of straight-line evolution because Equus is the only twig that survived. (See Stephen Jay Gould's essay "Life's Little Joke" in "Bully for Brontosaurus for more on this topic.) Second, horse evolution was not smooth and gradual. Different traits evolved at different rates, didn't always evolve together, and occasionally reversed "direction" Also, horse species did not always come into being by gradual transformation ("anagenesis") of their ancestors; instead, sometimes new species "split off" from ancestors ("cladogenesis") and then co-existed with those ancestors for some time. Some species arose gradually, others suddenly. Overall, the horse family demonstrates the diversity of evolutionary mechanisms, and it would be misleading — and would be a real pity — to reduce it to an oversimplified straight-line diagram... MORE
Horse Evolution Followed Twisty Trail, Study Says
The horse has been invaluable to humans since it was first domesticated in Central Asia some 6,000 years ago. Its speed and strength was harnessed to help us hunt prey, fight wars, work fields, and generally broaden our horizons. Without the horse, the course of human history might well look very different today. Less well known is the important role played by horses in shaping our understanding of a much deeper history — long-term evolution in animals. Writing this week in the journal Science, paleontologist Bruce J. MacFadden said the evolution of horses involved many more twists and turns than previously imagined... MORE
Ideas About Fossil Horses Undergo Evolution in Thinking
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The old gray mare, she ain’t what she used to be, says a University of Florida researcher whose findings show that the evolution of horses had more twists and turns than previously thought. According to conventional notions, horses simply became bigger over time and switched from being diminutive shrub nibblers to the statuesque, grass-eating masters of the open plains, said Bruce MacFadden, a U.F. paleontologist whose article appears in the journal Science. But the new horse sense is that the equine mammals are adaptable critters whose size, diet and range depended on geography and climate, he said. “The old ideas about how horses evolved made for a fairly simple and tidy story,” said MacFadden, whose 1992 book Fossil Horses is considered the definitive work on the subject. “But many of the concepts about horse evolution that came into being during the 20th century are now outmoded, giving way to an understanding of the fossil horse sequence that is much more complex.” Because horses have been around a long time, learning about their evolution provides unusual insight into the patterns of evolution in general... MORE
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