Zoology, Evolution and Speciation Flashcards Preview

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Flashcards in Zoology, Evolution and Speciation Deck (41)
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1

Approximately how many known species are there?

1.8 million

2

What is zoology

the study of animal life

3

Who is the first person we can attribute classifications to?

Greek Philosopher Aristotle

4

What can science do?

Science can only reject a hypothesis, it can not prove anything

5

Are all hypotheses scientific?

no, hypotheses that cannot be tested with science are not scientific

6

What is Lamarckian evolution

characteristics that are passed on
beefcake>beefcake!!>BEEFCAKE!!

7

What did Darwin propose?

Mechanisms

8

What mechanisms did Darwin propose?

Natural Selection
Nonrandom Mating
(These could lead to biodiversity and speciation)

9

What is the target of selection?

Natural selection targets the individual - you are what you are, your environment chooses if you are 'physically' successful

10

Where does the selective pressure originate?

The environment the specie lives in

11

Will selective pressures be the same in all places?

No because environments are different

12

Can an individual evolve?

No, an individual cannot evolve, a population evolves

13

What is evolution?

A change in a population over time

14

Explain: Directional Selection

Distribution is shifted in one direction
One extreme is selected for
Graph is a bell shape
X axis is the characteristic
Y axis is the number of individuals
The curve shows the range

15

Explain: Stabilizing Selection

Extremes are selected against
Pressures come from both sides, balance in both pressures

16

Explain: Disruptive Selection

Selecting against the average
Selecting for the extremes
Don't want to be in the average

17

What are the three modes of natural selection?

Stabilizing selection, disruptive selection, directional selection

18

What is the goal of nonrandom mating?

Maximizing fitness

19

What are mechanisms of evolution?

Selection and Drift

20

What are some Hardy-Weinburg Theorem assumptions?

The population is large
There is no migration
No mutation
Sexual reproduction is random
No natural selection

21

Does evolution always occur?

Yes because of mechanisms
Mutations always occur

22

Red Queen Hypothesis:

"It takes all the running you can do to stay in the same place"

23

Red Queen Hypothesis driver:

biotic interactions

24

Red Queen Hypothesis example:

bacterial resistance

25

Court Jester Hypothesis:

The environment is constantly changing but random abiotic events "change the rules" and accelerate biotic responses

26

Court Jester Hypothesis driver:

abiotic changes

27

Court Jester Hypothesis example:

volcanic explosions, soil turned over so now "you're" in the sun
unpredictable environment change

28

Microevolution:

Change in the frequency of alleles in a population over time

29

Microevolution mechanisms:

Mutation
Gene flow
Genetic Drift
Natural Selection
Non-random Mating

30

Microevolution occurs...

within a single population

31

Macroevolution:

Speciation - formation of new species

32

Macroevolution mechanisms:

Mutation
Gene flow
Genetic Drift
Natural Selection
Non-random Mating

33

Macroevolution occurs...

between populations

34

What are the four hypotheses for speciation?

Allopatric speciation
Peripatric speciation
Parapatric speciation
Sympatric speciation

35

What is Allopatric Speciation?

The formation of species through geographic barriers to gene flow
Think "Apart"
Allo->apart
Usually distances between subgroups greater than ability to move
After speciation no gene flow between these populations will occur even if they come into secondary contact

36

What is Sympatric Speciation?

The formation of species from a population that is not divided geographically
Reproductive barrier other than geography
Red fruit flies vs. Green fruit flies
Are the same and can reproduce but they don't
"Together"

37

What is Parapatric Speciation?

The formation of species from a population that is not divided geographically
Local adaptations cause differential fitness across geographical range
Hybrids are LESS successful
One species breeds and the offspring does not do well in the environment
Broad area and across the whole population
In-between "apart" and "together"

38

What is Peripatric Speciation

A small population isolated at the edge of a larger population
Specialized form of allopatric and/or parapatric speciation
Colony on the periphery has slightly different environment
Periphery colony changes
In-between "apart" and "together"

39

What is Hybrid Speciation?

Polyploid and Allopolyploid
Different Species interbreed
horses+donkey=mule
can be positive or negative
1/3 a new species

40

Speciation requires:

some level of reproductive isolation

41

Speciation is determined by:

Species
Environment
Time