LIFE SCIENCE

Detailed explanation-1: -If two or more species share a unique physical trait they may all have inherited this trait from a common ancestor. Traits that are shared due to common ancestry are homologous structures.

Detailed explanation-2: -Because genes build organisms, DNA carries a record of evolutionary relationships. Some genes are so fundamental that every living thing has them. These genes serve as a record that all life on Earth shares a common ancestor. Organisms that share a lot of traits generally have many more genes in common.

Detailed explanation-3: -Ancestral organism shared by two or more descendent lineages-in other words, an ancestor that they have in common. For example, the common ancestors of two biological siblings include their parents and grandparents; the common ancestors of a coyote and a wolf include the first canine and the first mammal.

Detailed explanation-4: -Scientists can compare the DNA of two organisms; the more similar the DNA, the more closely related the organisms. This method can also help when looks are deceptive. One example of looks being deceptive is: The bat and the crow both have wings, and the squirrel does not.

Detailed explanation-5: -Homologies are traits present in two or more organisms that were inherited from the common ancestor of those organisms.