QUESTION 7 A(n) describes the movement of nutrients through an ecosystem
O a. aquifer
O b. biogeochemical cycle
O c. ecotone
O d. primary production

the reason the two sea urchins don't compete with each other for food, resources, etc. is because the urchins have adapted to the environment but they have also adapted to each other. this is most likely because the genes of the sea urchins.

≅200-130 milions years ago pangea splited in 2 continents

the answer to your question is slate

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).