Darwin and Diversity Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

Explain how evolution is a fact.

A

Evolution has been observed and has definitely, undeniably occurred.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Explain how evolution is a theory.

A

The processes and mechanisms of evolution are debatable in regards to timing and methods, making this a theory.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the four lines of evidence for evolution?

A

Microevolution, macroevolution, imperfections, and molecular evidence.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is microevolution?

A

A small change within a species over a short period of time.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is macroevolution?

A

A large change between species over a long period of time.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How are imperfections proof of evolution?

A

Imperfections in the physical structures of organisms indicate their evolutionary history.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is an example of a physical imperfection in whales and what does it indicate?

A

Whales have an unnecessary pelvis, which indicates that they are descended from terrestrial mammals.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is an example of a physical imperfection in snakes and what does it indicate?

A

Snakes have vestigial hind limbs, which indicate that they are evolved from a lizard like creature.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Why is the appendix an imperfection in humans?

A

It is a remainder from when humans were unable to digest cellulose. It is now unnecessary, making it a physical imperfection.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why are wisdom teeth an imperfection in humans?

A

Wisdom teeth used to be able to fit in our mouths, but no longer can as our jaw shapes have changed. They are now detrimental, making them physical imperfections.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What does the coccygael tail indicate?

A

The coccygael tail vertebrae are left over from when humans used a tail for balance and support.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What two things are used as molecular evidence for evolution?

A

Amino acids and nucleotide sequences.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is a gene which is conserved across vertebrates?

A

The FoxP2 gene.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the FoxP2 gene used for? (3 things)

A
  1. Neural circuitry of the brain
  2. Sensory-motor information
  3. Learning of coordinated movements
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What happens to mice which don’t have the FoxP2 gene?

A

They can’t navigate mazes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What happens to birds which don’t have the FoxP2 gene?

A

They can’t learn songs.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What happens to people who don’t have the FoxP2 gene?

A

They have very delayed speech development or never develop speech.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What four observations are Darwin’s theory of evolution based on?

A
  1. Variation exists between individuals within a population.
  2. Genetic traits are inherited from parents by offspring.
  3. More offspring are produced than the environment can support.
  4. Many offspring do not survive long enough to reproduce.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What two inferences are Darwin’s theory of evolution based on?

A
  1. Individuals with favourable genetic traits are more successful at reproduction and have increased survival rates.
  2. Differential reproductive success results in an accumulation of favourable genes.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Explain how lactose tolerance is an example of microevolution.

A

Domestication of cattle arose 5,000 - 10,000 years ago. People who were able to digest lactose could then use milk as a source of energy and nutrients, making them stronger and fitter. This lead to differential reproductive success and positive selection for lactose tolerance genes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Define evolution.

A

Change in the genetic composition of a species over time. (aka descent with modification)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Define natural selection.

A

A process by which organisms with certain inherited traits have differential reproductive success due to those traits.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are the four main misconceptions about natural selection?

A
  1. Individuals change within their lifetime.
  2. Natural selection occurs because of a desire / need to adapt.
  3. All individuals are equally fit.
  4. Acquired traits can be passed on to offspring.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Define sexual selection.

A

Selection based on phenotypical characteristics which make mates more desirable or increases an individuals ability to compete for mates.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Define intrasexual selection.

A

Intrasexual selection is selection which occurs within a sex. It selects for body size and weapons.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is an example of intrasexual selection?

A

Male deer compete for mates through ritualised fighting, which selects for large antlers and large body sizes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Define intersexual selection.

A

Intersexual selection is selection which occurs between sexes, usually when a male tries to attract a female mate. This selects for behaviour, colour, and ornamentation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is an example of intersexual selection?

A

Male birds of paradise use bright colourings and courtships displays to try attract mates.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

How are adaptions based on sexual selection detrimental to organisms survival?

A

The elaborate structures selected for through sexual selection take energy to construct and make the individuals vulnerable to predation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Define stabilising selection.

A

Selection for the mean and against the extremes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is an example of stabilising selection?

A

Birth weight in humans. Very small babies are more vulnerable to health complications while very large babies are a risk for deadly birth complications.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Define directional selection.

A

Selection against one extreme and for the other extreme. This results in the mean shifting.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What are two situations where directional selection could occur?

A
  1. Change in the environment

2. Migration to a new environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is an example of directional selection? (turkeys)

A

Turkeys have been artificially selected to have extremely large breasts. They can no longer breed naturally because of their large breast size.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Define disruptive selection.

A

Disruptive selection selects for both extremes while selecting against the mean.

36
Q

What is an example of disruptive selection? (morph fish)

A

Morph fish have two variations; dwarf size and regular size. Dwarf size are able to hide in shells on lake beds and regular size fish are able to hide in rocky parts of the lake bed, but there is no where ideal for intermediate size fish.

37
Q

What is an example of disruptive selection? (coho salmon)

A

Coho salmon have Jack and Hooknose variations due to different reproductive strategies. Hooknose fish are large and aggressive, allowing them to find and defend mates. Jack fish are small and fast, allowing them to sneak fertilise other male’s mates.

38
Q

What are the five types of prezygotic isolation?

A

Temporal, ecological, behavioural, gametic, and mechanical.

39
Q

Define temporal isolation.

A

Isolation which occurs when species occur at different times during the day, month, or year.

40
Q

Define ecological isolation

A

Isolation which occurs when two species live in different habitats within the same area.

41
Q

Define behavioural isolation.

A

Isolation which occurs due to behaviour being used as mate recognition (eg courtship rituals).

42
Q

Define gametic isolation.

A

Isolation which occurs when the egg and sperms of two species are biologically incapable of fusing.

43
Q

Define mechanical isolation.

A

Isolation which occurs because physiological differences prevent breeding from occurring.

44
Q

What are the three types of postzygotic isolation?

A

Hybrid nonviability, hybrid sterility, and hybrid breakdown.

45
Q

Define hybrid nonviability.

A

Postzygotic isolation which disrupts embryonic development so that the embryo dies before birth.

46
Q

Define hybrid sterility.

A

Postzygotic isolation which ensures that hybrids can not fertilise or be fertilised.

47
Q

Define hybrid breakdown.

A

Postzygotic decline in hybrid fitness which results in the offspring being unable to survive and / or reproduce.

48
Q

How does the Biological Species Concept define a species?

A

As a group of organisms with a common gene pool which interbreed to produce fertile offspring.

49
Q

What five things are the Biological Species Concept unable to explain?

A
  1. Interbreeding species
  2. Reproductively isolated populations
  3. Extinct species
  4. Asexually reproducing species
  5. One species which is found in multiple areas
50
Q

How does the Phylogenetic Species Concept define a species?

A

The smallest group of organisms which shares a common ancestor and therefore has a unique genetic history.

51
Q

What is the Phylogenetic Species Concept based on?

A

Morphology and gene species.

52
Q

What species concept is used to identify cryptic species?

A

Phylogenetic Species Concept, as cryptic species are genetically distinct but they look identical.

53
Q

What is an example of a species pair?

A

The stickleback fish has two variations which have prezygotic and postzygotic isolation, but are not classifies as separate species.

54
Q

Define subspecies.

A

Members of the same species which are genetically and morphologically distinct but can still interbreed.

55
Q

Give an example of subspecies.

A

Hector’s dolphin and Maui’s dolphin are subspecies. They are geographically isolated, but can still interbreed.

56
Q

Define allopatric speciation.

A

Speciation which occurs when populations are isolated. This isolation is usually geographic first and then reproductive.

57
Q

What are four ways which geographic isolation can occur?

A
  1. Mountain formation
  2. Water rising to separate one land mass into smaller chunks
  3. Forest changing to grassland (or vice versa
  4. Large distances between two populations
58
Q

Define sympatric speciation.

A

Speciation which occurs when there is no isolation of populations.

59
Q

Give an example of sympatric speciation.

A

Adaptive radiation of the African Cichlid fish.

60
Q

How did the African Cichlid fish sympatrically develop different colouring?

A

Different wavelengths of light reach different depths of water. When males have colouring which corresponds to this colour they have better reproductive success. This means that the fish have different colouring at different depths.

61
Q

How did the African Cichlid fish sympatrically develop different shaped mouths?

A

The BMPH4 gene controls mouth morphology, and different species express this gene differently to suit their feeding habits.

62
Q

What do phylogenies show?

A

The evolutionary history of groups of organisms. It also shows how different species are related.

63
Q

Why can we not solely rely on morphology to construct phylogenies?

A

Convergent evolution causes analogous structures to develop. This could result in people thinking that species with analogous traits are much more closely related than they actually are.

64
Q

Define parsimony.

A

The idea that the phylogeny which requires the least evolutionary changes is the one which is most likely to occur.

65
Q

When did the Cambrian explosion occur?

A

~540 million years ago

66
Q

How long did the Cambrian explosion last for?

A

~20 million years.

67
Q

Why did reproduction on land take a long time to develop?

A

Terrestrial organisms could return to the water to reproduce.

68
Q

When did the Colonisation of Land occur?

A

~500 million years ago.

69
Q

What are three adaptions which were required for terrestrial organisms to develop?

A
  1. Breathing air
  2. Locomotion
  3. Desiccation prevention
70
Q

How many major mass extinctions have there been?

A

five

71
Q

What were the dates of the major mass extinctions?

A
  • 65.5MYA
  • 200MYA
  • 251MYA
  • 359MYA
  • 444MYA
72
Q

What is Impact Theory?

A

The theory that major mass extinctions may be due to meteorite impacts.

73
Q

How is the iridium layer proof of the Impact Theory?

A

Iridium is very rare on Earth but much more common in space. Therefore, the iridium layer in the fossil record is an indication of a meteor impact, and it has been dated at ~65MYA so it corresponds to a mass extinction.

74
Q

Where is the potential meteor impact site?

A

Yucatan Peninsula, Mexico

75
Q

How could the Earth’s orbit result in meteor impact?

A

The Earth’s orbit intersects the orbit of meteorites around every 26 million years, which could result in meteor impacts around these times.

76
Q

Define biogeography.

A

Geographic features which correlate with spatial distribution of life.

77
Q

What impact has continental drift had on New Zealand organisms?

A

New Zealand has been isolated for a very long time due to continental drift, so organisms here have evolved independently of other species.

78
Q

How has New Zealand’s land mass contributed to the presence of native predators?

A

New Zealand has a very small landmass which is unable to support large groups of large animals. This is a contributing factor to the lack of native populations.

79
Q

What do developmental genes do?

A

Control the rate, timing, and spatial pattern of growth.

80
Q

What is allometric growth?

A

The differences in relative growth rates of body parts in different species.

81
Q

What is homeosis?

A

The alteration in spatial arrangement of body parts.

82
Q

What did duplication of the Hox gene do?

A

This lead to the development of vertebrae, jaws, and limbs by repurposing preexisting structures.

83
Q

What are five activities which contributed to human induced evolution?

A
  1. Habitat loss
  2. Introduction of exotic species
  3. Pollution
  4. Climate change
  5. Human harvesting (fishing, hunting, farming etc)
84
Q

What are four effects of human harvesting?

A
  1. Abundance
  2. Growth rate
  3. Age at maturity
  4. Fecundity
85
Q

How does human induced selection effect sexually selected traits?

A

Males are usually larger due to sexual dimorphism, so are disproportionately selected against by size selective harvesting. This impacts sexual selection of the population as large males are selected against.
Male displays, as well as personal traits, are also selected against.