Ischyromys
Encyclopedia
Ischyromys is an extinct genus of rodent
from North America
.
The 60 cm (2 ft) long creature is one of the oldest rodents known. It resembled a mouse
and already had characteristic rodent incisor
s. Ischyromyss hind legs were longer than the forelegs, which could be used for other means than walking. Unlike most other mammals of its time, Ischyromys was probably arboreal (along with its relative Paramys
). It was a well-adapted climber that gradually beat out competition from rodent-like arboreal plesiadapiform
primate
s.
Rodent
Rodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....
from North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
.
The 60 cm (2 ft) long creature is one of the oldest rodents known. It resembled a mouse
Mouse
A mouse is a small mammal belonging to the order of rodents. The best known mouse species is the common house mouse . It is also a popular pet. In some places, certain kinds of field mice are also common. This rodent is eaten by large birds such as hawks and eagles...
and already had characteristic rodent incisor
Incisor
Incisors are the first kind of tooth in heterodont mammals. They are located in the premaxilla above and mandible below.-Function:...
s. Ischyromyss hind legs were longer than the forelegs, which could be used for other means than walking. Unlike most other mammals of its time, Ischyromys was probably arboreal (along with its relative Paramys
Paramys
Paramys is an extinct genus of rodent from North America, Europe, and Asia. It is one of the oldest genera of rodents known and probably lived in trees. While the genus name literally means "like a mouse", it coexisted with Thisbemys, a similar rodent, thus yielding a reference to Pyramus and...
). It was a well-adapted climber that gradually beat out competition from rodent-like arboreal plesiadapiform
Plesiadapiformes
Plesiadapiformes is an extinct order of mammals. It is either closely related to the primates or a precursor to them. Many are too derived to be ancestral to primates, but the earliest Plesiadapiformes have teeth that are strongly indicative of a common ancestor...
primate
Primate
A primate is a mammal of the order Primates , which contains prosimians and simians. Primates arose from ancestors that lived in the trees of tropical forests; many primate characteristics represent adaptations to life in this challenging three-dimensional environment...
s.