The terrestrial gastropods are the only mollusks that have adapted to all the habitats of the Earth. They dwell in areas of high altitude, mountainous regions, hot and cold places. Land snails live and perform their vital functions on the ground and not in the sea or bodies of fresh water.
D. Asteroids vary greatly in size and are mostly made up stone, iron and nickel
Answer:
Genetic variation that alter gene activity or protein function can introduce different traits in an organism. If trait is advantageous and helps the individual survive and reproduce, the genetic variation is more likely to be passed to the next generation (a process known as natural selection).
They begin to form about 3.8 billion years ago
