Editing Ground squirrel (section)

==Evolution and systematics==
[[File:Squirrel Mummy.jpg|thumb|left|20,000-year-old [[Arctic ground squirrel]] [[mummy]]]]

''[[Palaeosciurus]]'' from [[Europe]] is the oldest known ground squirrel species, and it does not seem to be particularly close to any of the two to three living lineages (subtribes) of Marmotini. The oldest fossils are from the [[Rupelian|Early Oligocene]], more than 30 [[Myr|million years ago]] (Mya), but the genus probably persisted at least until the mid-[[Miocene]], some 15 Mya.

Where the Marmotini originated is unclear. The subtribes probably diverged in the early to mid-[[Oligocene]], as primitive marmots and chipmunks are known from the [[Late Oligocene]] of North America. The [[fossil record]] of the "true" ground squirrels is less well known, beginning only in the mid-Miocene, when modern susliks and prairie dogs are known to have inhabited their present-day range already.

Whether the Marmotini dispersed between North America and Eurasia via "[[Oceanic dispersal|island-hopping]]" across the [[Bering Straits]] or the [[Greenland]] region—both of which were temperate [[habitat]] at that time—and from which continent they dispersed to which, or if both continents brought forth distinct subtribes which then spread to the other, is not known and would probably require more fossil material to be resolved. In any case, the fairly comprehensive fossil record of Europe—at the relevant time separated from Asia by the [[Turgai Sea]]—lacks ancient Marmotini except the indeterminate ''Palaeosciurus'', which might be taken to indicate an East Asian or western North American origin with trans-Beringia dispersal being the slightly more satisfying hypothesis. This is also supported by the enigmatic Chinese genus ''[[Sciurotamias]]'', which may be the most ancient living lineage of this group, or—if the chipmunks are not included here—close to the common ancestor of the Tamiini and the Marmotini ''sensu stricto''.

In any case, expansion of the Marmotini to Africa was probably prevented by [[competitive exclusion]] by their close relatives the [[Protoxerini]] and [[Xerini]]—the native terrestrial and palm squirrels of that continent, which must have [[evolved]] at the same time as the Marmotini did.

=== Size ===
Ground squirrels can measure anywhere from about {{convert|7.2|in|cm}} in height up to nearly {{convert|30|in|cm}}. They can weigh between {{convert|0.09|lbs|kg}} and {{convert|24|lbs|kg}}.<ref>{{Cite book|last=Karels|first=Tim|title=Grzimek's Animal Life Encyclopedia (Vol. 16: Mammals V. 2nd ed.)|publisher=Gale|year=2004|pages=143}}</ref>

=== Habitat ===
Open areas including rocky outcrops, fields, pastures, and sparsely wooded hillsides comprise their habitat.<ref>National Audubon Society Field Guide to Mammals</ref> Ground squirrels also live in grassy areas such as pastures, golf courses, cemeteries, and parks.

=== Defense mechanisms ===
Ground squirrels have developed several defense mechanisms to protect themselves from predators. When threatened, they emit high-pitched warning calls to alert others in their colony. This alarm call serves as an early warning system, allowing nearby squirrels to seek cover. The squirrels spend about one-third of their time standing to watch and when a predator is in sight, they stop and watch 60% of the time.<ref>{{Cite journal |last1=van der Marel |first1=Annemarie |last2=Marel |first2=Annemarie van der |last3=Waterman |first3=Jane M. |last4=López-Darias |first4=Marta |date=2021-10-16 |title=Barbary ground squirrels do not have a sentinel system but instead synchronize vigilance |url=https://www.technologynetworks.com/neuroscience/news/ground-squirrels-early-warning-system-is-revealed-355313 |journal=Behavioral Ecology and Sociobiology |language=en |volume=75 |issue=11 |pages=153 |doi=10.1007/s00265-021-03094-1 |bibcode=2021BEcoS..75..153V |issn=1432-0762|url-access=subscription }}</ref> Ground squirrels are also known for their burrowing behavior. They have intricate tunnel systems with multiple entrances, which provide escape routes from predators. When a threat approaches, they quickly retreat underground, where they are safe from most predators. Their burrows are designed with multiple chambers and ranges between {{convert|5|and|30|ft}},<ref>{{Cite web |title=Ground Squirrel / Home and Landscape / UC Statewide IPM Program (UC IPM) |url=https://ipm.ucanr.edu/home-and-landscape/ground-squirrel/pest-notes/#:~:text=California%20ground%20squirrels%20live%20in,between%205%20and%2030%20feet. |access-date=2023-10-25 |website=ipm.ucanr.edu}}</ref> making it challenging for predators to reach them. This combination of vocal warnings and burrow construction makes ground squirrels highly adapted to evade danger and survive in the wild.[[File:California Ground Squirrel.jpg|thumb|[[California ground squirrel]] (''Otospermophilus beecheyi'') in a tree]]

=== Diet ===
Ground squirrels are omnivorous, and not only eat a diet rich in fungi, nuts, fruits, and seeds, but also occasionally eat insects, eggs, and other small animals.<ref>{{cite web|title=Squirrels: Diet, Habits & Other Facts|website=[[Live Science]] |date=27 June 2014 |url=http://www.livescience.com/28182-squirrels.html}}</ref>

===Subtribes and genera===
[[File:Marmot-edit1.jpg|thumb|right|Watchful "rock chuck" or [[yellow-bellied marmot]] (''Marmota flaviventris'') atop [[Mount Dana]], [[Yosemite National Park]] in California]]
[[Basal (evolution)|Basal]] and ''[[incertae sedis]]'' genera
* {{extinct}}''[[Palaeosciurus]]'' ([[fossil]])<!-- Palaeontology 46(6): 1133-1149 -->
* ''[[Callospermophilus]]'' 
* ''[[Notocitellus]]''
* ''[[Otospermophilus]]'' (American rock squirrels)
* ''[[Poliocitellus]]'' (Franklin's ground squirrel)
* ''[[Sciurotamias]]'' (Chinese rock squirrels)
* ''[[Urocitellus]]''
* ''[[Xerospermophilus]]''
'''Subtribe Tamiina''': [[chipmunks]] (might be full tribe)
* ''[[Eutamias]]''
* ''[[Neotamias]]''
* {{extinct}}''[[Nototamias]]'' (fossil)
* ''[[Tamias]]''
'''Subtribe Marmotina''': marmots and prairie dogs
* {{extinct}}''[[Arctomyoides]]'' (fossil)
* {{extinct}}''[[Miospermophilus]]'' (fossil)
* {{extinct}}''[[Paenemarmota]]'' (fossil)
* {{extinct}}''[[Palaearctomys]]'' (fossil)
* {{extinct}}''[[Protospermophilus]]'' (fossil)
* ''[[Marmota]]''
* ''[[Cynomys]]'' (prairie dogs)
'''Subtribe Spermophilina''': true ground squirrels
* {{extinct}}''[[Spermophilinus]]'' (fossil)
* ''[[Ammospermophilus]]''
* ''[[Ictidomys]]'': [[Thirteen-lined ground squirrel]] and related species
* ''[[Spermophilus]]''