Editing Painted turtle (section)

===Fossils===
[[File:Top and bottom shell fossil Cf Chrysemys picta 01.jpg|thumb|right|alt=fossils in a tray, paper labels nearby|Top and bottom shell fossils, about 5&nbsp;million years old, from a Tennessee [[sinkhole]]<ref name=Williams>{{cite journal|last=Williams|first=Robert W|title=Mass grave from the remote past|journal=Norwegian Continental Shelf|date=2007-12-17|volume=2007|issue=3|url=http://www.npd.no/en/Publications/Norwegian-Continental-Shelf/No-3-2007/Mass-grave-from-the-remote-past/|access-date=2011-02-08|publisher=Norwegian Petroleum Directorate|format=also avail. as pdf}}</ref>]]

Although its evolutionary history—what the forerunner to the species was and how the close relatives branched off—is not well understood, the painted turtle is common in the fossil record.<ref name="Dobie">{{cite journal|last=Dobie|first=James L.|title=The taxonomic relationship between ''Malaclemys'' Gray, 1844 and ''Graptemys agassiz'', 1857 (Testudines: Emydidae) |journal=Tulane Studies in Zoology and Botany|date=1981–1982|volume=23|pages=85–103|url=https://archive.org/stream/tulanestudiesinz2319811982tula/tulanestudiesinz2319811982tula_djvu.txt|access-date=2011-01-04}}</ref> The oldest samples, found in Nebraska, date to about 15&nbsp;million years ago. Fossils from 15&nbsp;million to about 5&nbsp;million years ago are restricted to the Nebraska-Kansas area, but more recent fossils are gradually more widely distributed. Fossils newer than 300,000&nbsp;years old are found in almost all the United States and southern Canada.{{sfn|Ernst|Lovich|2009|pp=184–185}}