Which are characteristics of natural selection? Select three options.
It affects populations.
It affects only individuals.
It occurs when there is genetic variation.
It occurs when organisms are genetically identical.
It selects organisms with certain traits to survive.
It selects organisms at random to survive.

Which of the following observation darwin shape his concept of descent with modification? a) species diversity declines farther from the equator. b) fewer species live on islands than on the nearest continents. c) birds live on islands located farther from the mainland than the bird's maximum nonstop flight distance. d) south american temperate plants are more similar to the tropical plants of south america than to the temperate plants of europe. e) earthquakes reshape life by causing mass extinctions.