Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

ecology 2483 > Lecture 4- Chapter 6: > Flashcards

Lecture 4- Chapter 6: Flashcards

1
Q

Georges Cuvier

A
  • came before Darwin
  • discovered extinction in 1813
  • extinction was a wild notion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Carl

A
  • father of taxonomy
  • made thousands of species
  • coined the term homosapiens
  • christian
  • believed he was doing God’s work
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Charles Darwin

A
  • 1859: The Origin of Species
  • used the phrase “descent with modification”
  • natural selection (ex in book include hunting of bog horn sheep and cod fisheries)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is Evolution (3 points)

A
  1. Descent with Modification
  2. Allele Frequency Change
  3. Populations evolve, individuals do not
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Descent with Modification

A
  • Fossils: show descent with modification (In terms of teeth and limbs)
  • Species do change
  • Ex: stickleback fish, horses, and dinosaurs being extinct
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Allele Frequency Change

A

-allele frequency changes within a population
-Populations of organisms we do see variation within them
-If there is strong selection on a population, we will see genotype changes
- Ex. Arizona desert white sand mostly certain mice want to be cryptic from their predators so they are less visible than other mice within the population

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

Ecology Definition

A
  • the interaction between organisms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Populations Evolve, Individuals Do Not

A
  • evolution never follows over evolutionary time
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the Mechanisms of Evolution

A
  1. Mutation
  2. Natural Selection
  3. Genetic Drift
  4. Gene Flow
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Mechanism of Evolution 1. Mutation

A

-Individuals in populations differ in their phenotypes
-Different alleles arise by mutation
-Ex. Elephants utilize their tusks for manipulating their ecology
-Recently, poaching has been very popular in places where they live
-To get their tusks, they just slaughter the elephants, take off their faces, and leave the body to rot
-Mutation produces tuskless elephants

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

Mutation Definition

A

-a change in DNA
-Can result from copying errors during cell division, mechanical damage, exposure to chemicals (mutagens) or high-energy radiation
-Very rare
-Provides the raw material on which evolution is based, while recombination and independent assortment rearrange the raw material into new combinations

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

Mechanism of Evolution 2. Natural Selection

A

-beaks of birds
-Finches have massive bills used for cracking seeds

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

3 Types of Natural Selection

A
  1. Directional Selection
  2. Stabalizing Selection
  3. Disruptive Selection
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Directional Selection

A

-individuals at one phenotypic extreme are favoured
-Ex. large size
-Ex. the finches

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Stabalizing Selection

A

-individuals with an intermediate phenotype are favoured
-occurs if there is 2 selective agents operating on both sides of the curve
-Ex. 2 predators and the gall

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

Disruptive Selection

A
  • individuals at both phenotypic extremes are favoured
17
Q

Natural selection is the Mechanism of Adaptive Evolution

A
  1. What is Adaptive Evolution
  2. Adaptations results from natural selection
  3. Adaptive Evolution can Occur Rapidly
  4. Adaptations are not perfect
18
Q

Mechanism of Natural Selection 4. Gene Flow

A

-alleles move between populations via movement of individuals or gametes
-this causes:
1. Populations to become more similar
2. New alleles can be introduced into a population
-Ex. gene flow introducing alleles for insecticide resistance

19
Q

Key Conceot 3: Natural Selection is the Mechanism of Adaptive Evolution

A
  1. What is adaptive Evolution
  2. Adaptations result from natural slection
  3. Adaptive evolution can occur rapidly
  4. Adaptations are not perfect
20
Q

Adaptations Results from Natural Selection

A

-Selects of traits that confer advantages
-alleles increase in frequency over time

21
Q

Adaptive Evolution can Occur Rapidly

A
  • Male bighorn sheep that are bigger with a bigger horn will win the battle
  • Have been losing land (habitat has been deteriorating)
  • They will continue to be hunted- even tho hunters must pay $100,000
22
Q

Adaptations are not Perfect

A

-Natural selection does not result in a perfect match between organisms and their environments
-Environments are constantly changing, and there are constraints on evolution

23
Q

Why Evolution isn’t Perfect

A
  1. lack of genetic variation
  2. evolutionary history
  3. ecological trade-offs
24
Q

Lack of genetic variation

A
  • Spraying with DDT killed populations of mosquitoes carrying malaria
  • Killed off any form of mutations
25
Q

Evolutionary History

A

-Whales perfect example of evolutionary history
-Evolutionary Constraint: Whales always need to return to the surface to breathe

26
Q

Ecological Trade- offs

A
  • Crab: Decreased mobility due to size
  • Snow Crabs - claws are small but legs are long trying to get away from predators
27
Q

Adaptive Ecolution is Driven by Ecological Interactions

A

-Organisms interacting with one another and with their environment
-For every fox that caught a bunny, one fox went hungry
-Evolution is constantly in motion, and the ecological context is under constant change

28
Q

Key Concept 4: Long-term patterns of evolution are shaped by large-scale patterns

A

a. Speciation
b. Adaptive radiation
c. Extinction
d. Mass extinction

29
Q

What Drives Speciation in a Single Population:

A

-Change in gene frequency
-There is gene flow between white mice and dark mice
-But overtime a river continues to grow between the two
-At this particular point, no gene flow would be able to occur
-This would cause the formation of 2 separate daughter species (since gene flow isn’t occurring)

30
Q

Species Concept Definition

A

-Those individuals in the population must be able to have offspring, and those offspring should be fertile

31
Q

Physical Barriers that Result in Reproductive Isolation and Speciation

A
  • Physical Barrier
  • Mutualism (behaviour)
  • Ecological Barrier
32
Q

George Cuvier

A
  • discovered extinction
  • Over evolutionary time we have rates of extinction and speciation
33
Q

Adaptive Radiation Definition

A
  • Repeated speciation events increases the number of speciation in a group
34
Q

Extinction Definition

A
  • species are also lost
35
Q

An Evolutionary Tree Definiton

A
  • a branching diagram that represents the evolutionary history of a group
36
Q

Extant Definition

A
  • is the opposite of extinct (means they are alive today)
37
Q

What does the Cambrian Explosion mean?

A
  • adaptive radiation in animals
38
Q

Key Concept 5: Ecological Interactions and Evolution Exert a Profound Influence on one Another

A

Evolution observed patterns of change
- Bacteria and archaea
- Multicellular life - red algae
- Animal life

ecology 2483 (21 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions