Scientist have discovered many fossils of dinosaurs. However, they have not discovered any dinosaur's fossils in rock layers that are younger than
65 million years old. What conclusion can be drawn from this evidence?

Agenus is a taxonomic grouping that identifies a collection of species. when a scientist discovers a new species, how is this species assigned to a genus

Up until 1938, paleontologists accepted the idea that coelacanths (an ancient fish) went extinct at the time that they last appear in the fossil record, about 80 million years ago. but in 1938, a live coelacanth was discovered off the coast of south africa that was compared to the fossil record and found to be the same species what goal of science does this discovery represent

People with one sickle cell allele are not likely to get malaria. what is this an example of?