What term refers to four-limbed animals?
cephalopods
bipeds
tetrapods
pinnipeds

What makes a dominant allele different from a recessive allele

Explain how paleontologists use trilobite fossils as index fossils for various geologic time periods.

Where is having brightly colored feathers that attract mates most clearly an adaptation for a bird? a. a forest with dense vegetation b. a sandy beach beside an ocean c. a snowy tundra with little vegetation d. a swamp with many hawks that eat birds