Chalicotheriines are one of the two subfamilies of the extinct

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Chalicotheriidae, a group of

herbivorous A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthpar ...

odd-toed ungulate Odd-toed ungulates, mammals which constitute the taxonomic order Perissodactyla (, ), are animals—ungulates—who have reduced the weight-bearing toes to three (rhinoceroses and tapirs, with tapirs still using four toes on the front legs) o ...

''(perissodactyl)'' mammals that lived from the Eocene to the Pleistocene. The other subfamily is the

Schizotheriinae Schizotheriines are one of the two subfamilies of the extinct family Chalicotheriidae, a group of herbivorous odd-toed ungulate (perissodactyl) mammals that lived from the Eocene to the Pleistoscene. The other clade is the Chalicotheriinae. B ...

. Chalcotheriines evolved unique characteristics for ungulates, with very long forelimbs, short hindlimbs, and a relatively gorilla-like physique, including

knuckle-walking Knuckle-walking is a form of quadrupedal walking in which the forelimbs hold the fingers in a partially flexed posture that allows body weight to press down on the ground through the knuckles. Gorillas, bonobos, and chimpanzees use this style of ...

on their flexible forelimbs, which bore long curved claws. Members of this subfamily possessed some of the longest forelimbs and shortest hindlimbs in relation to each other out of all extinct animals. Analysis of dental wear implies that most chalicotheriines fed on seeds and fruit. Their claws were likely used in a hook-like manner to pull down branches, suggesting they lived as

bipedal Bipedalism is a form of terrestrial locomotion where an organism moves by means of its two rear limbs or legs. An animal or machine that usually moves in a bipedal manner is known as a biped , meaning 'two feet' (from Latin ''bis'' 'double' ...

browsers Browse, browser or browsing may refer to: Programs * Web browser, a program used to access the World Wide Web *Code browser, a program for navigating source code * File browser or file manager, a program used to manage files and related objects * ...

. Presence of chalicothere fossils is generally regarded as an indicator of forested environments. Unlike schizotheriines, chalicotheriines were typically confined to moist forests with a full tree canopy, and their lower-crowned teeth indicate a softer diet. While their appearance may look odd for an ungulate with a horse-like head, similar forms have evolved repeatedly in unrelated lineages: large herbivores that feed as bipedal browsers, standing or sitting upright and pulling down branches or stripping vegetation with clawed forelimbs. Examples include

therizinosaurs Therizinosaurs (once called segnosaurs) were large herbivorous theropod dinosaurs whose fossils have been found across the Early to Late Cretaceous deposits in Asia and North America. Various features of the forelimbs, skull and pelvis unite the ...

, the pantodont

Barylambda ''Barylambda'' (Greek: "heavy" (baros), "lambda" (lambda) in a reference to larger size than that of '' Pantolambda'') is an extinct genus of pantodont mammal from the middle to late Paleocene, well known from several finds in the Wasatchian ( N ...

, homalodotheres, and

megatheriid Megatheriidae is a family of extinct ground sloths that lived from approximately 23 mya—11,000 years ago. Megatheriids appeared during the Late Oligocene (Deseadan in the SALMA classification), some 29 million years ago, in South Amer ...

ground sloths. ''

Anisodon ''Anisodon'' (Greek: "unequal" (anisos), "teeth" (odontes)) is an extinct genus of chalicothere that lived in Europe during the late Miocene. It stood at about 150 cm and weighed around 600 kg. It is thought that the animal's clawed forelimbs wo ...

'' shows ischial callosities on the pelvis, a characteristic adaptation for sitting for long periods of time. Chalicotheriines are likely to have diverged as specialist feeders sitting in lush forests, similar to modern gorillas and giant pandas.

References

Pleistocene extinctions Miocene first appearances Fossil taxa described in 1914 {{paleo-oddtoedungulate-stub

See also

References