Which scientific evidence would show that two species of birds are closely related

Scientists will probably look at the birds' beaks, feathers, skeletal structure to see if they are closely related.

This is called evolutionwhich Charles Darwin discovered in 1859. He went to the Galápagos Islands. He found finches and other kinds of birds. He realized that some of the birds looked a lot alike but they had just one thing different about them. Charles realized that usually the thing that was different was something that would help them survive easier. Some birds had a longer beak for grabbing bugs while others had thicker beaks to crack open seed pods. 

1.fossils 2.analogous organs 3.homologous organs

Interacting group of various species in a common location. for example, a forest of trees and undergrowth plants, inhabited by animals and rooted in soil containing bacteria and fungi, constitutes a biological community.