The Xerinae comprise a

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end botanical subfamily names with "-oideae", and zo ...

squirrel Squirrels are members of the family Sciuridae (), a family that includes small or medium-sized rodents. The squirrel family includes tree squirrels, ground squirrels (including chipmunks and prairie dogs, among others), and flying squirrel ...

s, many of which are highly terrestrial. It includes the

tribes The term tribe is used in many different contexts to refer to a category of human social group. The predominant worldwide use of the term in English is in the discipline of anthropology. The definition is contested, in part due to conflict ...

Marmotini (

marmot Marmots are large ground squirrels in the genus ''Marmota'', with 15 species living in Asia, Europe, and North America. These herbivores are active during the summer, when they can often be found in groups, but are not seen during the winter, w ...

chipmunk Chipmunks are small, striped rodents of subtribe Tamiina. Chipmunks are found in North America, with the exception of the Siberian chipmunk which is found primarily in Asia. Taxonomy and systematics Chipmunks are classified as four genera: '' ...

prairie dog Prairie dogs (genus ''Cynomys'') are herbivorous burrowing Marmotini, ground squirrels native to the grasslands of North America. There are five recognized species of prairie dog: black-tailed prairie dog, black-tailed, white-tailed prairie dog ...

s, and other

Holarctic The Holarctic realm is a biogeographic realm that comprises the majority of habitats found throughout the continents in the Northern Hemisphere. It corresponds to the floristic Boreal Kingdom. It includes both the Nearctic zoogeographical reg ...

ground squirrels),

Xerini Xerini is a tribe of ground squirrels occurring in Africa and Asia. With the tribes Marmotini (Holarctic ground squirrels) and Protoxerini (African tree squirrels), they form the subfamily Xerinae. There are five living genera—'' Xerus'', the ...

(African and some Eurasian ground squirrels), and

Protoxerini The Protoxerini comprise a tribe of squirrels found in Africa. The 30 species in six genera are:Thorington, R. W. and R. S. Hoffmann. 2005. Family Sciuridae. Pp 754–818 in Mammal Species of the World A Taxonomic and Geographic Reference. Johns ...

(African tree squirrels). The Xerinae first originated in

Eurasia Eurasia ( , ) is a continental area on Earth, comprising all of Europe and Asia. According to some geographers, Physical geography, physiographically, Eurasia is a single supercontinent. The concept of Europe and Asia as distinct continents d ...

but later dispersed to other parts of the world. One of which was

Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

, where they traveled via land bridges in the

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

period, leading to the emergence of

and

ground squirrel tribes. Many Xerinae also dispersed to

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

during the early

Oligocene The Oligocene ( ) is a geologic epoch (geology), epoch of the Paleogene Geologic time scale, Period that extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that defin ...

era, and with the help of global cooling and the expansion of grasslands, resulted in the emergence of the Marmotini ground squirrel tribe.

Taxonomy

Tribe

six species of ground squirrels in five genera, occurring in Africa and Asia. :'' Atlantoxerus'' :'' Euxerus'' :'' Geosciurus'' :'' Spermophilopsis'' :'' Xerus'' Tribe

thirty species of tree squirrels in six genera, occurring in Africa. :'' Epixerus'' :'' Funisciurus'' :'' Heliosciurus'' :'' Myosciurus'' :'' Paraxerus'' :'' Protoxerus'' Tribe Marmotini ground squirrels in fifteen genera, occurring world wide. Includes the

prairie dogs Prairie dogs (genus ''Cynomys'') are herbivorous burrowing ground squirrels native to the grasslands of North America. There are five recognized species of prairie dog: black-tailed, white-tailed, Gunnison's, Utah, and Mexican prairie dogs. ...

, the marmots (including woodchuck), and chipmunks. :'' Ammospermophilus'' :'' Callospermophilus'' :'' Cynomys'' :'' Eutamias'' :'' Ictidomys'' :'' Marmota'' :'' Neotamias'' :'' Notocitellus'' :'' Otospermophilus'' :'' Poliocitellus'' :''

Sciurotamias ''Sciurotamias'' is a genus of rodent in the family Sciuridae, found in China. It contains the following species: * Père David's rock squirrel (''Sciurotamias davidianus'') * Forrest's rock squirrel (''Sciurotamias forresti'') References

...

'' :''

Spermophilus ''Spermophilus'' is a genus of ground squirrels in the Sciuridae, squirrel family. As traditionally defined the genus was very species-rich, ranging through Europe, Asia and North America, but this arrangement was found to be paraphyletic to ...

'' :'' Tamias'' :'' Urocitellus'' :'' Xerospermophilus''

References

Xerinae Mammal subfamilies Taxa named by Henry Fairfield Osborn {{Squirrel-stub