Editing Hagfish (section)

===Eye===
The hagfish eye lacks a lens, [[extraocular muscles]], and the three motor cranial nerves (III, IV, and VI) found in more complex vertebrates, which is significant to the study of the [[Evolution of the eye|evolution of more complex eyes]]. A [[parietal eye]] is also absent in extant hagfish.<ref>{{cite book|author=Ostrander, Gary Kent|title=The Laboratory Fish|url=https://books.google.com/books?id=Hp4YSFiSD0IC&pg=PT129|year=2000|publisher=Elsevier|isbn=978-0-12-529650-2|pages=129–|access-date=2016-03-13|archive-date=2024-08-29|archive-url=https://web.archive.org/web/20240829210925/https://books.google.ps/books?id=Hp4YSFiSD0IC&pg=PT129&redir_esc=y#v=onepage&q&f=false|url-status=live}}</ref><ref>{{cite web|url=http://www.physorg.com/news115919015.html|title=Keeping an eye on evolution|date=2007-12-03|access-date=2007-12-04|publisher=PhysOrg.com|archive-date=2012-03-15|archive-url=https://web.archive.org/web/20120315125907/http://www.physorg.com/news115919015.html|url-status=live}}</ref> Hagfish eyespots, when present, can detect light, but as far as it is known, none can resolve detailed images. In ''Myxine'' and ''Neomyxine'', the eyes are partly covered by the trunk musculature.<ref name=r1/> [[Paleontological]] evidence suggests, however, that the hagfish eye is not [[Cladistics#Terminology_for_character_states|plesiomorphic]] but rather degenerative, as fossils from the [[Carboniferous]] have revealed hagfish-like vertebrates with complex eyes. This would suggest that ancestrally Myxini possessed complex eyes.<ref>{{Citation| last1 = Gabbott | first1 = S.E | last2 = Donoghu | first2 = P.C | last3 = Sansom | first3 = R.S | last4 = Vinther | first4 = J | display-authors = 2 | title = Pigmented anatomy in Carboniferous cyclostomes and the evolution of the vertebrate eye. | journal = Proc. R. Soc. B | volume = 283 | issue = 1836 | pages = 20161151 | year = 2016 | doi = 10.1098/rspb.2016.1151 | pmid = 27488650 | pmc = 5013770 }}</ref><ref>{{Citation| last1 = Bardack | first1 = D | title = First fossil hagfish (Myxinoidea): a record from the Pennsylvanian of Illinois | journal = Science | volume = 254 | issue = 5032 | pages = 701–3 | year = 1991 | doi = 10.1126/science.254.5032.701 | pmid = 17774799 | bibcode = 1991Sci...254..701B | s2cid = 43062184 }}</ref>