Which of the following populations would be least likely to survive a change in its ecosystem? a. brown bears that can eat a variety of different kinds of food b. koalas that eat only eucalyptus leaves c. grasses that can grow in normal or contaminated soil d. bacteria that can grow in both hot and cold environments

The images show two species of tree frogs in a particular region. the gray tree frogs are adapted to the trees of the woodlands, while the green tree frogs can survive in woodlands or grasslands. the gray frog was abundant in the woodlands. because of climatic changes, most of the trees in the region died, and the woodlands changed to grasslands. in such a case, the . the gray tree frog is closely related to the green tree frog genetically, but they have different mating calls. this suggests that speciation occurred because of .