Astyanax mexicanus is a species of tetra fish that dwells in bodies of water deep inside caves. even though they cannot see, these fish still have small, nonworking eyes. their eyes are examples of which type of structures?

1. in what ways have non-native species been beneficial? 2. what are some of the hypotheses for the collapse of honeybee colonies? 3. distinguish between regional and functional extinction. 4. why is it difficult to measure background extinction rates? 5. what three factors are most important in causing extinction rates to climb?