Answer:the decline of lichens is an important indicator of an imbalance in the ecosystem. this research can help system ecologists predict how pollution will affect the entire ecosystem
Explanation:
The correct answer would be D, gravity. As moving water will cause rocks to erode as well as wind, and animal habitation.
Answer:
Some challenges animals might face when migrating are disease, global climate change, overexploitation, and habitat destruction.
Explanation:
In virtually every corner of the globe, migratory animals face a growing array of threats, including habitat destruction, overexploitation, disease, and global climate change. Saving the great migrations will be one of the most difficult conservation challenges of the 21st century.
