It is convergent revolution
The correct answer is an accumulation of microorganisms in deep marine environments.
Chalk rock refers to a pure form of limestone produced in tropical and warm seas about 100 million years ago in the Cretaceous period. The microscopic marine algae known as coccoliths thrived in the ancient seas. Their shells were comprised of calcite. With the death of the algae, their bodies sunk to the floor of the sea and sediment of chalk got deposited.
Over many years layers of chalk sediment got deposited and resulted in compaction of loose sediment into solid chalk rock.
Answer:
Originally, the distinction was based on morphological differences. However, it soon became that some types of organisms had different forms at various stages in their lives, here is why
Explanation:
changed genes is passed on to the next generation. Most mutations are bad, but some of them make the organism more successful in its life. Organisms that inherit that favorable new gene are likely to become more abundant than others of the species. (geologic times)
Answer:
Habitat is a place in which organisms live, and niche is the way in which an organism fits into its habitat