Im pretty certain it is volcanic eruption
Answer:
having exactly the same DNA sequences, twins start accumulating genetic variation from the earliest stages of development, researchers at Iceland-based company deCODE genetics found, meaning that one twin harbors variants that aren't present in the other.
Earthquakes occur because of the pressure and density.
Answer: Systematics
Explanation:
Systematics is the study of diversity of organisms including past and present and relationships among living things. Systematics as analytical approach, help us to understand the diversity and relatedness of both existing and extinct organisms. Systematics is also important in carrying out the conservation issues because, it attempts to explain the biodiversity which is related to different kinds of species and could be used in preservation and protect the endangered animals and plants.