LIFE SCIENCE

Detailed explanation-1: -Darwin noticed three distinctive patterns of biological diversity: (1) Species vary globally, (2) species vary locally, and (3) species vary over time.

Detailed explanation-2: -His discoveries included four different species of giant ground sloth (some of the largest land mammals ever to have lived), a gomphothere and the remains of an extinct horse. Many of Darwin’s fossils survive, at the Museum and elsewhere.

Detailed explanation-3: -Darwin traveled around the world and took notice of the different animals he encountered. In South America, he found rheas. In Africa, he saw a similar flightless bird, the ostrich. In Australia, he found the emu.

Detailed explanation-4: -The mechanism that Darwin proposed for evolution is natural selection. Because resources are limited in nature, organisms with heritable traits that favor survival and reproduction will tend to leave more offspring than their peers, causing the traits to increase in frequency over generations.