Sea-floor spreading, new crust is added at a .amid-ocean ridgebmagnetic stripe

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

Nucleic acids offer variability because they contain alternate forms of genes called .

Which areas of earth receive the most precipitation on average? a. tropics b. temperate zones c. regions near 30? n and s latitudes d. polar zones 1