Conservationists to restore ecosystems. which activity will positively affect the abiotic conditions of an ecosystem? keeping lakes and rivers free of pollution. planting new trees to provide food for animals. monitoring the ecosystem for bacterial pathogens that can cause illness. mating endangered animals in captivity and restoring them to their natural habitat.

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 .