Capillaries have thin walls, only one cell thick, that allow them to effectively perform their function.
C. The population has been growing very quickly
Answer:
with adequate supporting details (in the wet years there were more small seeds, so natural selection would have favored birds with thinner beaks because they could eat the smaller seeds
Explanation:
Answer:
natural resources
Explanation:
materials such as air, water, and soil and energy in nature that are essential or useful to humans.