Citation Hunt

Leaderboard

The Wikipedia snippet below is not backed by a reliable source. Can you find one?

Click I got this! to go to Wikipedia and fix the snippet, or Next! to see another one. Good luck!

In page Mexican tetra:

This text has been unreferenced on Wikipedia for a very long time. If you can't find a source, be bold and remove it!

"

Modern genetics has made clear that the lack of use does not, in itself, necessitate a feature's disappearance.[12][13] In this context, the positive genetic benefits have to be considered, i.e., what advantages are obtained by cave-dwelling tetras by losing their eyes? Possible explanations include:

  • There remains less chance of accidental damage and infection, since the previously useless and exposed organ is sealed with a flap of protective skin. It is unknown why this species did not develop transparent skin or eyelids instead, as some species of reptiles did.
  • The lack of eyes disables the "body clock", which is controlled by periods of light and dark, conserving energy. However sunlight does have minimal impact on the "body clock" in caves.[citation needed]