Air changes saved 3. This diagram shows two populations of a species that have been long separated by a river, which prevents interbreeding. The two populations differ in coloration, as shown in the diagram. Recent human activity has caused the river to dry, however, resulting in the two populations shown in the lower diagram. What is the most likely explanation for this change? 2005 Population 1 2015 Population 1 00 00 ● ● River River Population 2 。 00 •oo o O Human disturbance of river 2005 Population 2 ● Purple coloration O Yellow coloration ● Blue coloration An increase in gene flow between the two populations O An increase in nonrandom mating between the two populations O A decrease in gene flow between the two populations O A decrease in nonrandom mating between the two populations 5. What is the best definition of adaptation? O A trait or behavior that aids a population's survival and reproduction O A heritable trait or behavior that aids an organism's survival and reproduction O A heritable trait or behavior that aids a population's survival and reproduction O Atrait or behavior that aids an organism's survival and reproduction All changes saved 6. Antibiotics are medicines that are designed to kill disease-causing organisms, or pathogens. However, some pathogens evolve antibiotic resistance, where they gain traits that allow them to survive in the presence of antibiotics. The ability of bacteria to adapt to antibiotics so quickly has created a huge concern over whether antibiotics are being overused. What form of evolution is antibiotic resistance an example of, and why? O Mutation because each bacterium must mutate to an antibody-resistant form in order to survive O Gene flow because the bacteria are passing on the resistant trait within their populations O Genetic drift because medical workers cannot follow the randomly fluctuating gene frequencies of bacterial populations O Natural selection because the bacteria are adapting to a new environmental condition: the presence of the antibiotic 8. Which situation is most likely an example of convergent evolution? O Flowers that look very different have the same reproductive organs. O Some fish that live in total darkness have eyes. O Hawks and other birds have feathers. O Worms and snakes both move without legs.