Answer:
1. Are all species related? Yes. Just as the tree of life illustrates, all organisms, both living and extinct, are related.
2.A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction.
3. What role does sex play in evolution? Sexual reproduction allows an organism to combine half of its genes with half of another individual's genes, which means new combinations of genes are produced every generation.
4. Evolution is not a random process. The genetic variation on which natural selection acts may occur randomly, but natural selection itself is not random at all.
5. Evolution and "survival of the fittest" are not the same thing. Evolution refers to the cumulative changes in a population or species through time. "Survival of the fittest" is a popular term that refers to the process of natural selection, a mechanism that drives evolutionary change.
6. New traits can also come from transfer of genes between populations, as in migration, or between species, in horizontal gene transfer. Evolution occurs when these heritable differences become more common or rare in a population, either non-randomly through natural selection or randomly through genetic drift. There are four principles at work in evolution—variation, inheritance, selection and time.
