What term names preserved remains or traces of organisms from the distant past?

Shell fossils from successively younger layers differ in shape. What additional evidence would most strengthen the interpretation that they represent evolutionary change within a lineage?

In an undisturbed sequence of sedimentary rock layers, which fossil is usually oldest?

Which field investigates where species occur across Earth's regions and how those patterns have changed through time?

Mesosaurus fossils occur in similarly aged rocks in South America and Africa. Assume the reptile could not cross a wide ocean. Which explanation best accounts for this distribution?

Closely related finches on different Galápagos islands have different beak shapes suited to local foods. Which explanation best fits this pattern?

Which approach studies similarities and differences in organisms' body forms?

Human arms, bat wings, whale flippers and cat forelegs perform different tasks, yet they share the same basic arrangement of bones. What best explains this shared arrangement?

The five-fingered hands of humans and other apes share an evolutionary origin. How are these structures classified?

Bird and bat wings evolved independently as flight surfaces. How are they classified when considering this flight function?

What makes a structure vestigial?

Which statement about the human appendix is accurate?

Early fish, chicken and human embryos all have pharyngeal arches and a tail, though the adults differ greatly. What do these shared temporary features suggest?

Scientists trace how pharyngeal regions develop into adult structures in humans and fish. Which type of evolutionary evidence are they comparing?

Which information directly supplies molecular evidence of evolutionary relationships?

Liza compares corresponding DNA regions in three species. A and B have fewer differences than A and C. What does this usually suggest?

Which organism shares the most recent branching point with the tarsier in this tree?

A newly discovered species resembles a dolphin externally. Which comparison would best help scientists investigate whether that resemblance reflects close evolutionary relatedness?

Which idea from Charles Lyell helped Darwin explain how species could change gradually?

What idea from Thomas Malthus helped Darwin develop natural selection?