have a single pair of continuously growing incisors in both the upper and lower jaws. have a...

Rodentia

Christopher Palau

Definition/Facts• Have a single pair of continuously growing incisors in both the

upper and lower jaws.

•  Have a diastema, or a gap between the incisors and the cheek teeth.

• 43% of all mammals are rodents

• There are 30 families, and 1,620 species known worldwide.

• They are found nearly everywhere becausethey are extremely adaptable

6 Families in PASciuridae, Castoridae, Muridae, Dipodidae, Erethizontidae, Cricetidae

History• First rodents were around 66 million years ago.

• First direct relatives of modern rodents were 20 million years ago. (beaver)

• Horned Gopheronly horned rodent

• 2.5 mya

CastoridaeBeaver

Castor canadensis

Largest rodent in

North America

ErethizontidaeNorth American Porcupine

Erethizon dorsatum

• Quills are modified hairs• Only predator is the fisher

DipodidaeMeadow Jumping MiceZapus hudsonius

Woodland Jumping MiceNapaeozapus insignis

CricetidaeSubfamily Arvicolinae (lemmings, voles, and muskrat)

• Rock Vole• Meadow Vole• Woodland Vole• Southern bog lemming• Southern red-backed vole• Muskrat

SubfamilyNeotominae (North American rats/mice)

• Woodrat• Deer mouse• White-footed mouse

Old world rats and mice

Muridae

1) House mouse (Mus musculus)2) Norway rat (Rattus norvegicus)3) Black Rat (Rattus rattus)

1

2 3

SubfamilySciurinae(tree squirrels and flying squirrels)• Gray Squirrel• Fox squirrel• Red squirrel• Northern flying squirrel• Southern flying squirrel

SciuridaeSquirrels, chipmunks, marmots

SubfamilyXerinae(chipmunks and ground squirrels)• Woodchuck• Eastern Chipmunk• Thirteen-lined ground squirrel

Found only in Mercer and Venango counties