Editing Thermoregulation (section)

===Hibernation, estivation and daily torpor===
To cope with limited food resources and low temperatures, some mammals [[hibernation|hibernate]] during cold periods. To remain in "stasis" for long periods, these animals build up [[Brown adipose tissue|brown fat]] reserves and slow all body functions. True hibernators (e.g., groundhogs) keep their body temperatures low throughout hibernation whereas the [[core temperature]] of false hibernators (e.g., bears) varies; occasionally the animal may emerge from its den for brief periods. Some bats are true hibernators and rely upon a rapid, non-shivering thermogenesis of their brown fat deposit to bring them out of hibernation.<ref name="Harding Mifsud 2017 p. 15">{{cite book | last1=Harding | first1=J.H. | last2=Mifsud | first2=D.A. | title=Amphibians and Reptiles of the Great Lakes Region, Revised Ed. | publisher=University of Michigan Press | series=Great Lakes Environment | year=2017 | isbn=978-0-472-05338-4 | url=https://books.google.com/books?id=hEc_DwAAQBAJ&pg=PA15 | access-date=2023-07-28 | page=15}}</ref>

[[Aestivation|Estivation]] is similar to hibernation, however, it usually occurs in hot periods to allow animals to avoid high temperatures and [[desiccation]]. Both terrestrial and aquatic invertebrate and vertebrates enter into estivation. Examples include lady beetles (''[[Coccinellidae]]''),<ref>{{cite journal |author=Kenneth S. Hagen |year=1962 |title=Biology and ecology of predaceous Coccinellidae |journal=[[Annual Review of Entomology]] |volume=7 |pages=289–326 |doi=10.1146/annurev.en.07.010162.001445}}</ref> [[Desert tortoise|North American desert tortoises]], [[crocodile]]s, [[salamander]]s, [[cane toad]]s,<ref>{{Cite web |url=http://www.audubonguides.com/article.html?id=27 |publisher=[[Audubon Guides]] |title=Estivation: The Survival{{sic|hide=n}} Siesta |date=29 September 2009 |author=Bob Moore |access-date=24 October 2013 |archive-date=21 November 2018 |archive-url=https://web.archive.org/web/20181121010717/http://www.audubonguides.com/article.html?id=27 |url-status=dead }}</ref> and the [[Cyclorana platycephala|water-holding frog]].<ref>{{cite book |author=F.H. Pough |author2=R.M. Andrews |author3=J.E. Cadle |author4=M.L. Crump |author5=A.H. Savitzky |author6=K.D. Wells |year=2001 |title= Herpetology, second edition |publisher= Prentice Hall |location=Upper Saddle River, New Jersey}}</ref>

Daily [[torpor]] occurs in small endotherms like [[bat]]s and [[hummingbirds]], which temporarily reduces their high metabolic rates to conserve energy.<ref>{{cite book |title=Biology: Concepts and Applications |first=Cecie |last=Starr |year=2005 |publisher=Thomson Brooks/Cole |pages=[https://archive.org/details/biology00ceci/page/639 639] | isbn=978-0-534-46226-0 |url=https://archive.org/details/biology00ceci
|url-access=registration |quote=cold temperatures birds minimize heat loss. }}</ref>