Chapter 5- Evolution And Biodiversity

Question 1

What is th mechanism of evolution?

Answer 1

By natural selection

Question 2

What provides evidence for evolution?

Answer 2

The fossil record

Question 3

There are 3 parts of evidence of evolution, what is the 1st?

Answer 3

1) the sequence in which fossils appear match the sequence in which they would be expected to evolve
Bacteria and simple algae appearing first, fungi and worms and land vertebrates

Question 4

There are 3 parts of evidence of evolution, what is the 2nd?

Answer 4

2) sequence fits in with the ecology of groups- plant fossils before animals, plants on land before animals

Question 5

There are 3 parts of evidence of evolution, what is the 3rd?

Answer 5

Many sequences of fossils are known, which link together existing organisms with their likely ancestors

Question 6

What does selective breeding of domesticated animals show?

Answer 6

That artificial selection can cause evolution

Question 7

What is artificial selection?

Answer 7

Massive changes between domesticated animals and the wild version of them- explanation is that the change has been achieved simply by repeatedly selecting for and breeding the individuals most suited to human use

Question 8

What does evolution of homologous structures by adaptive radiation explain?

Answer 8

Similarities in structure when there are differences in function

Question 9

What is convergent evolutions

Answer 9

There are similarities between structures of animals like fish tales and whales and these are know as analogous structures- when studied there actually very different however interpretation is that they have had different origins and have become similar because the perform the same or similar functions

Question 10

What are homologous structures do to with evolution

Answer 10

Can look different and perform a different function but they are called a ‘unity of type’ as an example in the forelimbs of humans, bats, horse, mole and porpoise is that they have the same bones in the same relative positions despite on the surface looking very different

Question 11

What is the evolutionary explanation of homologous structures

Answer 11

Adaptive radiation- they have had the same origin, from an ancestor that had a pentadactyl or 5- digit limbs - become different because they form different functikns

Question 12

What are rudimentary organs?

Answer 12

Organs that have no use anymore so are gradually being lost

Question 13

What are the adaptions of amphibians, reptiles, birds and mammals with their pentadactyl Lims?

Answer 13

1) reptiles- crocodiles walk or crawl on land and use their hind limbs for swimming
2) Birds- penguins use their hind limbs for walking and their forelimbs as flippers for swimming
3) Mammals- echidnas use all four limbs for walking and use their forelimbs for digging
4) amphibians- frogs use all four limbs for walk f and hindlimbs for jumping

Question 14

What can populations of species gradually diverge into?

Answer 14

Separate species by evolution

Question 15

How can populations of species diverge into separate species?

Answer 15

If two populations of a species become separated so that they do not interbreed and natural selection then acts differently on the two populations, they will evolve in different ways

Question 16

What is the process of speciation?

Answer 16

Two populations of species, evolve- characteristics gradually become different until they become reconsibly different - if populations merge and do not interbreed it would be clear they have evolved into separate species

Question 17

What is more evidence of patterns of variation?

Answer 17

Continuous variation across the geographical range of related populations matches the concept of gradual divergence

Question 18

Explain the development of melanistic insects in polluted areas

Answer 18

Dark variations of typically light coloured insects are called melanistic - examples= Biston betularia- widely used as an example of natural selection- as the melanistic variety becomes better cAmouflaged the then the pale one - why?- they fly at night and try to mate, during the day they’re on trees, birds and other predators hunt during the day etc

Question 19

When does evolution occur?

Answer 19

When heritable characteristics of a species change