CSHS 12 ATAR Biology Evidence for Evolution

Fossils are the preserved remains and traces of organisms. There are few fossils of the earliest forms of life because:

• they only lived in water and water does not preserve organisms well.

• they were mostly soft-bodied organisms, which are not preserved well.

• there was no oxygen around to preserve them.

• archaeologists have not searched deeply enough into old rocks to find them.

archaeologists have not searched deeply enough into old rocks to find them.

• A Tyrannosaurus rex that was killed by a falling tree in a forest

• A spider trapped in the sap of a tree

• A penguin frozen in a glacier

• An elephant that has become trapped in a cave

Modern horses belong to the genus Equus, which have one toe modified into a hoof. They are descended from various genera; the oldest being Hyracotherium, which had four toes on its front feet and three toes on its back feet. The toes had pads similar to those of modern dogs. In between Hyracotherium and Equus, there was Parahippus, which walked on its middle toe. The bones of the side toes were fused to the middle toe and the outside toes no longer touched the ground. It no longer had pads. Parahippus would be classified as:

• a vestigial form.

• a transitional form.

• an evolutionary dead end.

• an antiquated form.

Absolute dating techniques are based on:

• fossils found in a particular layer of rock.

• the number of atoms present in a substance.

• a comparison between the isotopes in the fossils and the isotopes in the rock the fossil is in.

• radioactive decay of naturally occurring isotopes.

Which of the following is NOT part of Darwin’s theory of natural selection?

• Individuals with favourable traits do not pass these on to the next generation.

• Some individuals have an advantage over others in the population.

• Populations gradually change in order to become better suited to the environment.

• More individuals are born than can survive, producing competition within a species.

Fossils of various species of marsupial have been found in Antarctica, South America and Australia. Yet today marsupials are only found in Australia. The fact that fossils have been found outside of Australia is an example of:

• continental evolution.

• convergent evolution.

• biogeography

• phylogeny

Lake Victoria is an isolated lake that formed recently (in a geological sense) in the African rift valley. In just 15 000 years, more than 300 species of cichlid fish arose from one parent species. This is an example of:

• biogeography

• speciation

• adaptive radiation.

• convergent evolution.

Wings can be found in many types of animal. Pterosaurs – winged lizards – were the first creature (other than insects) to have wings. Birds, bats and insects also have wings. For these organisms, wings are:

• analagous structures and suggest no recent common ancestor.

• analagous structures and suggest a recent common ancestor.

• homologous structures and suggest no recent common ancestor.

• homologous structures and suggest a recent common ancestor.

Which of the following statements about embryology supports the theory of evolution?

• The embryos of dogs and frogs have similar vertebrate features.

• Fossil embryos are similar to the embryos of today.

• Embryos have similar vestigial structures.

• Embryos often produce new species through mutations.

A similar set of bones is seen in the forearm of a human and a whale; both mammals. This is an example of:

• homologous structures.

• analagous structures.

• vestigial structures.

• convergence