Editing Sea turtle (section)

== Description ==

For each of the seven species of sea turtles, females and males are the same size. As adults, it is possible to tell male turtles from female turtles by their long tails with a cloacal opening near the tip. Adult female sea turtles have shorter tails, with a cloacal opening near the base. Hatchling and sub-adult turtles do not exhibit [[sexual dimorphism]]; it is not possible to determine their sex by looking at them.<ref name="SWOT">{{cite web|url=https://www.seaturtlestatus.org/articles/2020/2/27/how-to-tell-if-a-turtle-is-male-or-female|title=How to Tell if a Sea Turtle is Male or Female|website=The State of the World's Sea Turtles|access-date=30 October 2023|date=2023-10-23}}</ref>

In general, sea turtles have a more [[fusiform]] body plan than their [[Terrestrial animal|terrestrial]] or freshwater counterparts. This tapering at both ends reduces volume and means that sea turtles cannot retract their head and limbs into their shells for protection, unlike many other turtles and tortoises.<ref name="defenders">{{cite web|url=http://www.defenders.org/sea-turtles/basic-facts|title=Sea Turtles|website=Defenders of Wildlife|access-date=15 October 2015|date=2012-03-20}}</ref> However, the streamlined body plan reduces friction and drag in the water and allows sea turtles to swim more easily and swiftly.

The leatherback sea turtle is the largest sea turtle, reaching 1.4 to more than 1.8 [[Metre|m]] (4.6 to 5.9 ft) in length and weighing between 300 and 640 [[Kilogram|kg]] (661 to 1,411 lbs).<ref name="Leatherback Turtle">{{cite web|url=https://www.seaturtlestatus.org/leatherback-turtle|title=Leatherback Turtle|website=The State of the World's Sea Turtles|access-date=30 October 2023|date=2023-10-30}}</ref> Other sea turtle species are smaller, ranging from as little as 60 cm (2 ft) long in the case of the Kemp's ridley, which is the smallest sea turtle species, to 120 cm (3.9 ft) long in the case of the green turtle, the second largest.<ref name="auto"/><ref>{{cite web|url=http://www.turtlehospital.org/sea-turtle-species/|title=Sea Turtle Species|website=turtlehospital|access-date=29 August 2015}}</ref>

The skulls of sea turtles have cheek regions that are enclosed in bone.<ref name="Jonesetal2012">{{Cite journal|last1=Jones|first1=MEH|last2=Werneburg|first2=I|last3=Curtis|first3=N|last4=Penrose|first4=RN|last5=O'Higgins|first5=P|last6=Fagan|first6=M|last7=Evans|first7=SE|date=2012 |title=The head and neck anatomy of sea turtles (Cryptodira: Chelonioidea) and skull shape in Testudines|journal=PLOS ONE|volume=7|issue=11|pages=e47852|doi=10.1371/journal.pone.0047852|pmid=23144831|pmc=3492385|bibcode=2012PLoSO...747852J|doi-access=free}}</ref><ref name="Chatterjietal2020">{{Cite journal|last1=Chatterji|first1=RM|last2=Hutchinson|first2=MN|last3=Jones|first3=MEH|date=2020 |title=Redescription of the skull of the Australian flatback sea turtle, ''Natator depressus'', provides new morphological evidence for phylogenetic relationships among sea turtles(Chelonioidea) |journal=Zoological Journal of the Linnean Society|volume=191|issue=4|pages=1090–1113|doi=10.1093/zoolinnean/zlaa071}}</ref> Although this condition appears to resemble that found in the earliest known fossil reptiles (anapsids), it is possible it is a more recently evolved trait in sea turtles, placing them outside the anapsids.<ref name="Zardoyaetal1998">{{Cite journal|last1=Zardoya|first1=R|last2=Meyer|first2=A|date=1998 |title=Complete mitochondrial genome suggests diapsid affinities of turtles |journal=Proceedings of the National Academy of Sciences |volume=95|issue=24|pages=14226–14231|doi=10.1073/pnas.95.24.14226|pmid=9826682|pmc=24355|bibcode=1998PNAS...9514226Z|doi-access=free}}</ref><ref name="Jonesetal2012"/>