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Blind cave tetra — printable fact sheet
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Blind cave tetra
Astyanax mexicanus
The blind cave tetra is the same species as an ordinary, fully eyed silver river fish, Astyanax mexicanus, and that is what makes it so valuable. Surface fish washed into caves in northeastern Mexico have independently lost their eyes and pigment on at least thirty separate occa…
Did you know?
- Some populations of blind cave tetras have evolved independently in different cave systems, making them a classic example of convergent evolution.
- Cave fish from different caves lost their sight through different mutations, and crossing two blind populations can produce sighted offspring, because each supplies the gene the other broke. The albinism gene knocked out in several cave populations is oca2 — the same gene involved in human albinism. Cave tetras "sense" walls by generating their own water movement and reading the reflection, effectively a hydrodynamic form of echolocation.
What I learned
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