Grass -> Grasshopper -> Mouse-> Hawk
If there is 10,000kg of biomass available at the producer level, how much biomass is available for the secondary consumer?

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).

there are so many examples for that in different areas, like biology experiment carried out in our lab recently.

here's one link:

the answers are a and c