Evidence for Evolution

Question 1

What is artificial selecion?

Answer 1

Variation in a species generated by human driven selection

Selecting on morphology

Question 2

What are some examples of artifical selection?

Answer 2

Pigeons

Dogs

Crops such as wheat and beets

Question 3

What is allopolyploidy?

Answer 3

When a hybrid of two different parent species has double the chromsome number

Question 4

How many plant species are polyploids?

Answer 4

40 - 70%

Question 5

What does allopolyploidy lead to?

Answer 5

Instant speciation

Question 6

What are the biogeographical rules?

Answer 6

Bergmann’s rule - Animals get larger further north

Allen’s rule - animals in colder climates have thicker limbs

Lack’s rule - the clutch size of each species has evolved to an evolutionary optimum

Rensch’s rule - sexual dimorphism increases with average body size

Question 7

What do the biogeograohucal rules tell us?

Answer 7

There are common adaptive responses of organisms in different places

All rules show variation in traits due to the environment (evidence for evolution)

Question 8

Which of the gull species are most distantly related?

Answer 8

Herring gull and Lesser Black-Backed gull

Question 9

What is the Italian sparrow a hybrid of?

Answer 9

House and Spanish sparrows

Question 10

What was used to map the evolution of horses?

Answer 10

Fossilised foreleg and teeth structure

Teeth structure also allowed palaebiological reconstruction

Question 11

What do transitional forms in fossils allow us to do?

Answer 11

Allows us to show the evolutionary links between two major groups

Archaeopteryx allwoed bird and reptile phylas to be linked together as has both characteristics

Question 12

What are homologous characters?

Answer 12

Traits that are inherited from a common ancestor

Despite being inherited, may now serve different functions

Question 13

What do homologous characters show?

Answer 13

Different groups have evolved from a common ancestor

Also shows they have diverged

Question 14

Give an example of a characteristic being homologous and not homolgous at the same time

Answer 14

Wing and bird bat wings

The bones show homology as they are the same

The wings are not homolgous (analogous) due to structure differences

Question 15

What are vestigial characteristics? Give some examples

Answer 15

Structures that serve no function

Whales have pelvis bones and humans have an appendix

Question 16

What does the presence of vestigial characters show?

Answer 16

Evidence of evolutionary relationships

Evidence of evolutionary change

Question 17

Give some examples of universal homology

Answer 17

DNA

Transcription

Translation

Proteins