Reading:
Convergent Evolution
Evolution is the process in which, over time, animals develop the characteristics required to survive in their natural environment. One form of this is convergent evolution, which is when animals living in completely separate geographic areas end up with many identical features. This occurs when the habitats of two creatures resemble each other in some way. Because they live in similar habitats, the animals end up needing similar specialties in order to survive and reproduce. In certain cases the animals are so alike that they may end up being mistaken for each other, while in other cases they only share a few features.
Listening:
Question:
Using the details and examples given in the listening, explain the concept of convergent evolution.
Sample Answer:
According to the reading convergent evolution is when animals living far apart from each other evolve the same features or characteristics. The professor elaborates on this. First, he explains why antelope and pronghorns look similar. He says that their habitats are distant from each other, but both are flat grasslands with few trees. They need to be able to notice predators quickly and escape from them. As a result, both species have evolved legs and lungs that help then run quickly, and huge eyes that improve their vision. Next, he explains that bats and dolphins share a unique feature. He mentions that bats live in dark caves and hunt at night and that dolphins live in the ocean, which is also very dark. To survive without being able to see well, both species have evolved to use echolocation to spot objects in their surrounding environment.