Talk:Plica semilunaris of conjunctiva

Latest comment: 5 years ago by Hairy Dude in topic Vestigial organ?

Contradictory information

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I'm not an editor, in fact I'm thinking I'm not even writing this in the right place, but this article claims that there is only one species of primate with a functional nictitating membrane, but most lemurs have one. Can someone fix this? https://en.wikipedia.org/wiki/Lemur#Senses

It has contradictory information about the third eyelid.— Preceding unsigned comment added by Zsendukas (talkcontribs) 23:19, 29 April 2007 (UTC)Reply

Vestigial organ?

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How can it be a vestigial organ when it has a purpose (secreting rheum, to remove debris from the eye)? —Preceding unsigned comment added by Rmeden (talkcontribs) 14:46, 20 June 2009 (UTC)Reply

Human vestigiality defines a vestigial trait as one that has lost "all or most" of its original function. This is certainly true of the plica semilunaris - it has lost much function, but not all. Hairy Dude (talk) 14:09, 11 May 2019 (UTC)Reply

Not vestigial in everyone

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The nictitating membrane is not a vestigial remnant in everyone. I know this because I have a functioning, but involuntary, nictitating membrane. Mine is white and opaque. I was told that this trait is common in Northern China and Mongolia, but I have never been able to confirm this. Does anybody know of a reference? (I am white and from european ancestry, not that it matters.) HairyWombat 21:48, 8 December 2011 (UTC)Reply