Biogeographic isolation refers to the separation of the members of the similar species, or a group of organisms, which breed and generate offspring that can further give rise to young ones.
The separation can be achieved by the geographical forces like oceans, rivers, and mountains, and by the biological forces, like hunting times, and spring or fall mating.
Answer:
The Laura tried to grow micro-organisms in culture broth medium in Petri-plates but the microbial growth was not observed even on the fourth day of culture which could be due to:
1. Laura could have not provided the correct broth medium maintaining the with pH and salt concentrations.
2. Microorganisms did not get optimal growth conditions.
3. The bacterial source could have died after the collection which could have lysed after their death and thus no longer visible.
D. An element donates an electron to another element.
A movement of alleles resulting from migration. I hope I helped