Answer:
Prehistoric
Explanation:
The Prehistoric Period—or when there was human life before records documented human activity—roughly dates from 2.5 million years ago to 1,200 B.C. It is generally categorized in three archaeological periods: the Stone Age, Bronze Age and Iron Age.
Variations in evolution usually refers to variation of genes at a particular loci. This differs from diversity which is the total of genetic differences within a population. Speciation is the reproductive isolation of a subset of a population.
Answer:
A biotic factor is a living organism that shapes its environment. In a freshwater ecosystem, examples might include aquatic plants, fish, amphibians, and algae. Biotic and abiotic factors work together to create a unique ecosystem.
There are 7 levels of classification for Animals. Kingdom, Phylum, Classes, Order, Families, Genus, and Species.