What are some ways organisms in the Galapagos Islands have evolved to fit into their special habitat?

One example of evolution on the islands are the differences in the beaks of the species of finches found on each island. Depending on which island you are on, there are different species of finches with different sized and shaped beaks that are best for what ever food source they exploit. Birds of one island may have small thin beaks for catching insects while the inhabitants of another may have big thick beaks for cracking open nuts and seeds.

As for the phytoplankton, they are autotrophic and require light to power photosynthesis in order to survive, therefore do well in the well lit photic zone.