AP BIOLOGY

Detailed explanation-1: -The Galpagos tortoises share a common ancestor, but have necks of different lengths to best reach the food they need in their environment. This kind of evolution is proven by DNA analysis and results in organisms with different ancestors becoming more alike as they adapt to similar environments.

Detailed explanation-2: -The most studied animals on the Galápagos are finches, a type of bird (Figure below). When Darwin first observed finches on the islands, he did not even realize they were all finches. But when he studied them further, he realized they were related to each other. Each island had its own distinct species of finch.

Detailed explanation-3: -A classic example of natural selection at work is the origin of giraffes’ long necks. The ancestors of modern giraffes were animals similar to deer or antelope, with necks of ordinary length.

Detailed explanation-4: -Dolphins, penguins, and sharks are distantly-related species that share similar characteristics which help them live in water. This is an example of CONVERGENT evolution.

Detailed explanation-5: -The Galapagos finches evolved through natural selection from a common ancestor into a wide variety of different looking species with different kinds of beaks.