1
Scientists can compare the order of ______ ______ in a protein to see how closely related two species are.
2
In an effort to understand how evolution may have occurred, Darwin studied the _____ selection of domesticated animals.
3
Members of a species can be cut off from the rest of the species when a natural ________ such as a river, separates group members.
4
Over time, different finches developed different ______ shapes and sizes that were well suited to the food that they ate.
6
There is ______ among members of a species because food, space and other resources are limited.
8
Any difference between individuals of the same species is called a ______.
9
Darwin discovered many differences among organisms on the different _______ Islands.
11
Darwin was amazed by the _______ of living things. That is the great variety of living things.
13
Darwin was a _______, a person who observes and studies the natural world.
15
An organism's body structure is its basic body plan, which in vertebrates includes how its ____ are arranged.
16
Charles Darwin traveled around the world on the British ship HMS _______.
17
_______ states that evolution occurs slowly and steadily.
20
Similarities in the development of the embryos of different species suggests they share a _______ ancestor.
23
The bones in a bird's wing, a dolphin's _____, and dog's leg have similar structures.
24
When comparing the DNA of two species, the more similar the DNA sequences, the more ____ related the species.
27
A scientific ______ is a well-tested concept that explains a wide range of observations.