Evidence for Evolution

Question 1

Define ‘evolution’.

Answer 1

The process of cumulative changes in the heritable characteristics of a species or population over time.

Question 2

Define ‘homology structures’.

Answer 2

Physical features shared due to an evolutionary history (common ancestor).

Question 3

Define ‘analogus structures’.

Answer 3

Different origins/structure but have the same or similar function.

Question 4

Give examples of analogus structures.

Answer 4

• Butterfly and bird wings
• Fish and penguin flippers/fins
• Crab and turtle shells
• Turtle and bird beaks

Question 5

Define ‘vestigial structures’ and gives examples.

Answer 5

Structures that serve no apparent function (evolutionary leftovers).

• Human tailbone
• Whales hind leg bones
• Snakes underdelveloped legs

Question 6

Define ‘molecular biology’ and give examples.

Answer 6

Code used to translate nucleoid sequences into amino acids is the same in all organisms.

*Humans share 98% of their genetic code with chimpanzees and 64% with chickens

Question 7

Define ‘fossil record’.

Answer 7

Fossils are preserved remains of previously living organisms or their traces.
Contained in rock layers called strata, which acts as a sort of timeline.

Question 8

Define ‘biogeography’ and give examples.

Answer 8

The geographic distribution of organisms on Earth follows patterns that are best explained by evolution, in combination with the movement of tectonic plates over geological time.

*Marsupials exist almost exclusively in Australia

Question 9

Define ‘artificial selection’ and give examples.

Answer 9

Intentional reproduction of individuals in a population that have desirable traits.

• Dog breeds
• Crops (fruits, vegetables, grains)
• Cattle (sheep, cows)

Question 10

Define ‘speciation’.

Answer 10

Over time if enough changes occur in a population, a new species can arise, as they have become so distinctly different from one another that they are each different species.

Question 11

Define ‘direct evolution’ and give examples.

Answer 11

Sometimes evidence for evolution is that we observe it over time taking place directly around us.

• Drug-resistant bacteria
• Pesticide-resistant insects

Question 12

Define ‘comparative embryology’ and give examples.

Answer 12

Some homologous structures can only be seen in embryos.

*Vertebrate embryos all have tails and gill slits

Question 13

Define ‘homologous genes’ and give examples.

Answer 13

The idea that two species have the same gene, inherited from a common ancestor.

*Varying versions of the eyeless gene control eye formation in many animals