The discovery of tropical plant and animal fossils in antarctica support the idea that at one time this continent supported a climate. colder drier warmer harsher

warmer

Explanation:

The discovery of remains of a tropical plant on the continent of Antarctica indicates that a tropical climate once existed on what is now a frozen land. For instance, the finding of glossopteris, which is an ancient and extinct species of plant in South America, Africa, Asia, Australia and Antarctica.

genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).

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