Selective breeding and human food security | Starter Quiz | Oak National Academy

Why are there no fossils younger than 10 000 years?

• No animals or plants have died in the right conditions for fossilisation.

• Only dinosaurs left fossils.

• There are gaps in the fossil record.

• The process of fossilisation takes thousands of years.

Answer explanation

The mineralisation of the once living remains of fossils is a slow process.

Match the words to their meaning.

• fossil record

• An ancestor species shared by several other species.

• extinct

• All the fossils ever found.

• transitional species

• A species with characteristics between an ancestor and a later species

• evolution

• Changes in the characteristics of a species over many generations.

• Common ancestor

• A species which has no living individuals remaining anywhere.

Answer explanation

The fossil record is incomplete and so many transitional species either left no fossils or the fossils have yet to be found.

Which layer of sedimentary rock will contain the youngest fossils?

Answer explanation

The top layer a is the youngest so will contain the youngest fossils.

Scientists think *Archeopteryx* and modern birds share a common ancestor, but there is a gap in the fossil record. Why are there gaps in the fossil record?

• All plants and animals form fossils.

• Not all fossils have yet been discovered.

• Scientists don’t know what the fossils look like.

• Many fossils rot away leaving no trace.

Answer explanation

Over time, gaps in the fossil record are being filled as more fossils are found but it is likely there will always be gaps.

Which species is the common ancestor?

Answer explanation

Species C and D are more closely related to each other than they are to species B, but all three share a common ancestor in species A.

The diagram shows a suggestion for the evolution of the hippopotamus and some modern whales. Which statement is correct?

• Whales evolved from the hippopotamus.

• The hippopotamus evolved from whales.

• Whales and the hippopotamus are not related.

• Whales and the hippopotamus share a common ancestor.

Answer explanation

Whales and the hippopotamus share a common ancestor. The hippopotamus is most closely related to the sperm whale, but the sperm whale is more closely related to the other whales than to the hippopotamus.