Basic Perissodactyl
Info
A perissodactyl is an odd-toed ungulate (hoofed mammal). The order perissodactyla contains several sub categories of animals including horses, rhinos, titanotheres, tapirs, chalicotheres, and several other interesting creatures that appeared in North America during the Paleocene, not long after the dinosaur extinction. Only horses, rhinos, and tapirs survive today. Below is a very quick run-down of some perissodactyls worth noting.
Brontotheres/Titanotheres
Brontotheres were a highly successful group of perissodactyls that roamed the North American forests during the Eocene, starting about 55 million years ago. They started small (Eotitanops) and looked much like the Palaeotheres. Before dying out in the late Eocene, they became the largest and most impressive beasts to roam North America. They looked much like strange rhinos, but stood a massive 8 feet tall, similar in size to Asian elephants.
Chalicotheres
Tapirs are strange looking perissodactyls, but are nowhere near as odd as the chalicotheres. Chalicotheres roamed North America, Europe, Africa, and Asia starting in the Eocene. While some chalicotheres looked like horses with claws, others had a stance very similar to that of a gorilla. Their long front limbs ended in sharp claws, which may have forced them to be knuckle-walkers. Their claws, gorilla stance, and horse-like head have earned chalicotheres a well-deserved place as one of the strangest-looking mammals to live. They died out in the early Pleistocene.
Horses
Horses evolved from animals like Mesohippus. Though they started out with three toes per foot, they now only have one toe per leg (or foot, depending on how you look at it).
Hyracodon
Also common in the Eocene of North America, and looking much like an early horse, Hyracodon is called “the running rhino” due to the fact that it had rhino-like teeth and was lightly built. Though it had rhino-like teeth and was called the “running rhino”, it wasn’t a true rhinoceros and was the last in its direct evolutionary lineage. The later and very similar Subhyracodon from the Oligocene, however, was a true rhino (despite the fact that it also had no horns).
Hyracotherium (Eohippus)
Hyracotherium was one of the earlier perissodactyls, evolving in the early Eocene roughly 60 million years ago. It had a wide spread-Europe, Asia, and North America. Though its original name (Eohippus) means “dawn horse”, and it was indeed once classified as a horse, it is no longer considered a true equid but, rather, a palaeothere. It would have looked like a tiny horse and was about a foot tall. An interesting note: Hyracotherium had four toes on the front feet, and three on the back-very similar to titanotheres.
Mesohippus
Abundant in North America, Mesohippus evolved roughly 40 million years ago in the late Eocene. It would have resembled Hyracotherium, but was twice as tall. Mesohippus is considered an early, true horse.
Paraceratherium
Very closely related to Hyracodon (both were hyracodontids), Paraceratherium (also known as Indricotherium and Baluchitherium) was the largest land mammal to ever walk the planet. Standing an estimated 18 feet tall at the shoulder (25 feet at the top of the head) it weighed an estimated 45,000 lbs! Paraceratherium lived in the Eocene and Oligocene of Europe and Asia.
Rhinos
Rhinos initially evolved during the late Eocene in Eurasia and quickly spread throughout Asia, North America, and Africa. The famous Woolly Rhinoceros (Coelodonta antiquitatis) was closely related to the modern Sumatran Rhino, which is the most primitive of the exisiting rhino genra. Also, we have an idea what color Woolly Rhinos were from cave paintings. They would have been reddish brown with a dark brown band around the center of the body. Once numerous and successful, the rhinoceros range exists only in parts of Africa and Asia.
Tapirs
Tapirs are a rather small and odd-looking perissodactyl that originally evolved in the early Oligocene. They spread throughout Asia, South America, and North America, but they no longer exist in the latter continent. They have what looks like a small “trunk” (proboscis) and their teeth even bear a small similarity to those of the juvenile mastodon.
A perissodactyl is an odd-toed ungulate (hoofed mammal). The order perissodactyla contains several sub categories of animals including horses, rhinos, titanotheres, tapirs, chalicotheres, and several other interesting creatures that appeared in North America during the Paleocene, not long after the dinosaur extinction. Only horses, rhinos, and tapirs survive today. Below is a very quick run-down of some perissodactyls worth noting.
Brontotheres/Titanotheres
Brontotheres were a highly successful group of perissodactyls that roamed the North American forests during the Eocene, starting about 55 million years ago. They started small (Eotitanops) and looked much like the Palaeotheres. Before dying out in the late Eocene, they became the largest and most impressive beasts to roam North America. They looked much like strange rhinos, but stood a massive 8 feet tall, similar in size to Asian elephants.
Chalicotheres
Tapirs are strange looking perissodactyls, but are nowhere near as odd as the chalicotheres. Chalicotheres roamed North America, Europe, Africa, and Asia starting in the Eocene. While some chalicotheres looked like horses with claws, others had a stance very similar to that of a gorilla. Their long front limbs ended in sharp claws, which may have forced them to be knuckle-walkers. Their claws, gorilla stance, and horse-like head have earned chalicotheres a well-deserved place as one of the strangest-looking mammals to live. They died out in the early Pleistocene.
Horses
Horses evolved from animals like Mesohippus. Though they started out with three toes per foot, they now only have one toe per leg (or foot, depending on how you look at it).
Hyracodon
Also common in the Eocene of North America, and looking much like an early horse, Hyracodon is called “the running rhino” due to the fact that it had rhino-like teeth and was lightly built. Though it had rhino-like teeth and was called the “running rhino”, it wasn’t a true rhinoceros and was the last in its direct evolutionary lineage. The later and very similar Subhyracodon from the Oligocene, however, was a true rhino (despite the fact that it also had no horns).
Hyracotherium (Eohippus)
Hyracotherium was one of the earlier perissodactyls, evolving in the early Eocene roughly 60 million years ago. It had a wide spread-Europe, Asia, and North America. Though its original name (Eohippus) means “dawn horse”, and it was indeed once classified as a horse, it is no longer considered a true equid but, rather, a palaeothere. It would have looked like a tiny horse and was about a foot tall. An interesting note: Hyracotherium had four toes on the front feet, and three on the back-very similar to titanotheres.
Mesohippus
Abundant in North America, Mesohippus evolved roughly 40 million years ago in the late Eocene. It would have resembled Hyracotherium, but was twice as tall. Mesohippus is considered an early, true horse.
Paraceratherium
Very closely related to Hyracodon (both were hyracodontids), Paraceratherium (also known as Indricotherium and Baluchitherium) was the largest land mammal to ever walk the planet. Standing an estimated 18 feet tall at the shoulder (25 feet at the top of the head) it weighed an estimated 45,000 lbs! Paraceratherium lived in the Eocene and Oligocene of Europe and Asia.
Rhinos
Rhinos initially evolved during the late Eocene in Eurasia and quickly spread throughout Asia, North America, and Africa. The famous Woolly Rhinoceros (Coelodonta antiquitatis) was closely related to the modern Sumatran Rhino, which is the most primitive of the exisiting rhino genra. Also, we have an idea what color Woolly Rhinos were from cave paintings. They would have been reddish brown with a dark brown band around the center of the body. Once numerous and successful, the rhinoceros range exists only in parts of Africa and Asia.
Tapirs
Tapirs are a rather small and odd-looking perissodactyl that originally evolved in the early Oligocene. They spread throughout Asia, South America, and North America, but they no longer exist in the latter continent. They have what looks like a small “trunk” (proboscis) and their teeth even bear a small similarity to those of the juvenile mastodon.
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