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