Many animals have similar traits, such as having a or 4 legs. These characteristics are the result of having a ancestor.

The five types of vertebrates are , , , , and .

Characteristics of Fish:
- Live in
- Most are
- Some have
-

Characteristics of Amphibians:
- Born in
- Live in as an adult
- Some have legs

Characteristics of Reptiles:
- Live on
- Tough, waterproof
- Breathes through

Characteristics of Birds:
- Feathers and wings
-
- legs

Characteristics of Mammals:
- Live or eggs
- Fur and
- Bigger
- Feed

The 8 types of invertebrates are: , , , . , , , and .

An embryo is an or unhatched offspring that is developing from the egg. embryos can be compared to determine common .

DNA can be compared between to determine how similar they are. Human and chimpanzee DNA are % the same.

Body in modern organisms evolved from a structure in a ancestor. These structures can have different , but still have the same basic .

The six bones found in all tetrapod legs are , , , , , and .

The ancestor of modern whales walked on on land (terrestrial). remains of various species have been foumd.

Hominids are family that includes humans and their ancestors. Hominids split from other primates about million years ago.

Cladograms show the amount of relatedness among organisms based on the number of physical characteristics that they share. Before the discovery of , organisms that the same were believed to be .

Early embryos resemble each other because they shared/ from a ancestor. Animals with analogous structures usually share the same and have similar .

Amphibians, such as frogs, have a but not an amniote egg, but reptiles, such as lizards and birds, and mammals, such as humans and kangaroos, have the amniote egg because their offspring develop on .

Phylogenetic trees are more cladograms that show evolutionary where extinct ancestors are found at points, and extant species are at the of the tree.

All living organisms on Earth from a common ancestor but each species has evolved specific which allow them to and reproduce in the environment that they live in.