Wednesday, June 29, 2011

Prehistoric Mammal Week: Hyracotherium.


The creature above is likely the ultimate Uncanny Valley beast. Its name is Hyracotherium, it lived in Asia, Europe, and North America, and it was about the size of a fox. It lived during the early Eocene (52 mya) - a time when, for reference, we had a relative named "Necrolemur." Hyracotherium looks like a creature that we all should know, but do not. We've seen this animal before, but where? Goddammit, it's on the tip of my tongue...

You have got to be kidding me.That little guy? A horse? He's got to be smaller than the smallest horse in Guinness.

Actually, Einstein is only slightly bigger. Nice going, evolution.

Technically, Hyracotherium is no longer a horse. It's a palaeothere- a type of ancient mammal that shows the starting traits of being a perissodactyl (odd-toed ungulate). There is still some debate over exactly where it belongs, but it did give rise to horses, regardless of whether it can legally be considered an equine or not. The old name for it was Eohippus - "dawn horse."

Hyracotherium is the oldest known ancestor of the modern equines, including horses, asses, and zebras. It started as a small creature with the five digits common to tetrapods. As time went on,  these little fellows became faster and faster, as well as bigger and bigger from eating new plants.The horse family lost toes until only the center digit remained and became encased in a sturdy hoof. They also evolved to love sugar cubes (irony!).

Some scientists also propose that Hyracotherium founded other perissodactyl lines, such as rhinoceroses and tapirs. Those are pretty neat, too; tomorrow will feature a look at brontotheres, creatures that look like rhinos but may have been more closely related to horses. If only Nintendo had some creativity left; Hyracotherium would be a great fossil Pokemon to make a three-way evo out of.


  1. just so you know, the eohippus didnt "transition" into a horse. It simply was a different creature all together. There is literally no transitional fossils out there. If there were, wouldnt you think they would be very common, since creatures have been here for millions of years (so evolutionists claim)? Same for people. If we have been here for so long, and we came from apes, wouldnt you think you could come up with ONE full skeleton of a transition from ape to man? You cant, it simply can not be done. The religion of evolution defies two basic laws of science: 1st law of thermodynamics and the 2nd law of thermodynamics. Its common sense. Use your head. It takes more faith in believing in evolution than it does to say that a Creator created all this.

  2. "To be sure, an unbroken evolutionary connection does link Hyracoterium (formerly Eohippus) to modern-day Equus." - Stephen Jay Gould, "A Wonderful Life", 1989, p. 36. Obviously the comment by Shane Killen is misinformed. However, I would like to say that this article misses the point that this development from Hyracoterium to Equus is simply one of the many thousands of pathways "among thousands on a complex bush" (Gould, 1989) --- we cannot ignore the fact that this wasn't a direct transition; there was no ladder whose rungs are extinct species, which climbed towards Equus.

    1. Thank you. :) There are indeed many branches, but it happens that the one to Equus is the one most people know and care about. It's also very clear that the fastest of the Hyracotheria were the ones that spread, had babies (can I call them foals?) etc. No, it isn't as linear as we tend to make it out to be; that's a preference and oversimplification of science.

      So, yes, we tend to pigeonhole equine evolution. It's not quite as linear as that. That doesn't mean it is completely unprovable, nor that the stages are not easy to see. Working on a little something for Year of the Horse now, and happened upon my own entry. ;)