Editing Perissodactyla (section)

=== Lack of carotid rete ===
Unlike artiodactyls, perissodactyls lack a [[carotid rete]],<ref name="Mitchell Lust 2008 pp. 415–418">{{cite journal |last1=Mitchell |first1=G |last2=Lust |first2=A |date=2008-08-23 |title=The carotid rete and artiodactyl success |journal=Biology Letters |volume=4 |issue=4 |pages=415–418 |doi=10.1098/rsbl.2008.0138 |issn=1744-9561 |pmc=2610139 |pmid=18426746}}</ref> a heat exchange that reduces the dependence of the temperature of the brain on that of the body. As a result, perissodactyls have limited thermoregulatory flexibility compared to artiodactyls which has restricted them to habitats of low seasonality and rich in food and water, such as tropical forests. In contrast, artiodactyls occupy a wide range of habits ranging from the Arctic Circle to deserts and tropical savannahs.<ref name="Mitchell Lust 2008 pp. 415–418">{{cite journal |last1=Mitchell |first1=G |last2=Lust |first2=A |date=2008-08-23 |title=The carotid rete and artiodactyl success |journal=Biology Letters |volume=4 |issue=4 |pages=415–418 |doi=10.1098/rsbl.2008.0138 |issn=1744-9561 |pmc=2610139 |pmid=18426746}}</ref>