Australopiths with rugged jaws, flat faces, and enormous molars are known as

if the type of the food available changes, then the frequency of beak types will change, because birds with beaks more suited to the available food will be more successful over time.

any abiotic or biotic factor in an ecosystem that causes a population's size to slow or decrease is a limiting factor.

the answer is c. it will give up it's valence electron to the other atom.