What usually compresses the sedimentary rock layers?

In the african savanna, more wildebeests are born than the environment can support. which is most likely to happen over a period of years as a result

Leila has dimples because she received a gene copy from her father that coded for dimples. this means that dimples are an example of a trait that is

The finches on the galapagos island were similar in form except for variations of their beaks. darwin observed that these variations were useful for: attracting a mate defending territory building nests gathering food