Editing Blubber (section)

==Function==
Blubber is the primary fat storage on some [[mammal]]s, specifically those that live in water. It is particularly important for species that feed and breed in different parts of the ocean. During these periods, the animals [[metabolism|metabolize]] fat. Blubber may save energy for marine mammals, such as dolphins, in that it adds [[buoyancy]] while [[Whale#Locomotion|swimming]].<ref>{{cite web |url=http://www.sciencenetlinks.net/sci_update.php?DocID=10 |archive-url=https://web.archive.org/web/20130921054320/http://www.sciencenetlinks.net/sci_update.php?DocID=10 |url-status=dead |archive-date=2013-09-21 |website=Science Update |title=Bouncy Blubber |publisher=AAAS }}</ref>

Blubber differs from other forms of [[adipose tissue]] in its extra thickness, which provides an efficient thermal [[Thermal insulation|insulator]], making blubber essential for [[thermoregulation]]. Blubber is more vascularized—rich in [[blood vessel]]s—than other adipose tissue.

Blubber has advantages over fur (as in [[sea otter]]s) in that, though fur retains heat by holding pockets of air, the air expels under pressure (i.e., when the animal dives). Blubber, however, does not compress under pressure. It is effective enough that some whales can dwell in temperatures as low as {{convert|40|F|order=flip}}.<ref>{{cite web | url= https://www.pbs.org/oceanrealm/intheschool/school5.html | title= Secrets of the Ocean Realm | url-status= live | archive-url= https://web.archive.org/web/20170504042247/http://www.pbs.org/oceanrealm/intheschool/school5.html | archive-date= 4 May 2017}}</ref> While diving in cold water, blood vessels covering the blubber constrict and decrease blood flow, thus increasing blubber's efficiency as an insulator.<ref>{{cite book |author= Galbraith, Don|display-authors=et al |title=Biology 11 |location= Canada |publisher= McGraw-Hill Ryerson |page= 12}}</ref>

Blubber aids buoyancy and streamlines the body, because the organized, complex collagenous network supports the noncircular cross sections characteristic of cetaceans. The buoyancy of blubber could be problematic for bottom-feeding marine mammals such as [[sirenian]]s and the extinct [[Thalassocnus|marine sloths]], both of which do or probably did have limited amounts of it for that reason.<ref name="Horgan2014">{{cite journal|last1= Horgan|first1= P.|last2= Booth|first2= D.|last3= Nichols|first3= C.|last4= Lanyon|first4=J. M.|title= Insulative capacity of the integument of the dugong (''Dugong dugon''): thermal conductivity, conductance and resistance measured by in vitro heat flux|journal= Marine Biology|volume= 161|issue= 6|year= 2014|pages= 1395–1407|doi= 10.1007/s00227-014-2428-4|s2cid= 83824482}}</ref><ref name="Amson2015">{{Cite journal|last1= Amson|first1= E.|last2= Argot|first2= C.|last3= McDonald|first3=H. G.|last4=de Muizon|first4= C.|year= 2015|title= Osteology and functional morphology of the axial postcranium of the marine sloth ''Thalassocnus'' (Mammalia, Tardigrada) with paleobiological implications|journal= Journal of Mammalian Evolution|volume= 22|issue= 4|pages= 473–518|doi= 10.1007/s10914-014-9280-7|s2cid= 16700349}}</ref>

Research<ref>{{cite journal |doi= 10.1242/jeb.01559 |title= The ontogenetic changes in the thermal properties of blubber from Atlantic bottlenose dolphin Tursiops truncatus |year=2005 |last1=Dunkin |first1=R. C. |journal=Journal of Experimental Biology |volume=208 |issue=8 |pages=1469–80 |pmid=15802671|doi-access=free }}</ref> into the [[thermal conductivity]] of the common [[bottlenose dolphin]]'s blubber reveals its thickness and lipid content vary greatly amongst individuals and across life history categories. Blubber from emaciated dolphins is a poorer insulator than that from nonpregnant adults, which in turn have a higher heat conductivity than blubber from pregnant females and adolescents.