Brainscape's Knowledge GenomeTM

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


See full index

Evolution > Exam 2 Lecs - 3 > Flashcards

Exam 2 Lecs - 3 Flashcards

1
Q
  • 1.9 million described species

- … species estimated globally, could be as many as … species

A

9 million;

100 million

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

3 species concepts we’re focusing on:

  • …
  • …
  • …
A

morphospecies concept;
phylogenetic species concept;
biological

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q
  • none of the species concepts we currently have are sufficient definitions for all cases
  • … and … in traits can occur at the same time and place –> sometimes third stage of … doesn’t happen
  • the three stages of speciation aren’t necessarily followed in all cases
A

isolation;
divergence;
reproductive isolation

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

… is the first step of speciation:

- usually happens with … influence

A

isolation;

geographic

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

isolation is first step of speciation:

  • usually happens with geographic influence
  • for isolated populations, allele frequencies won’t be the same in both populations due to … and … –> thus, they start …
A

drift;
selection;
differentiating

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

geographic model of speciation is …

- occurs either through … or through …

A

allopatric model;
dispersal;
vicariance

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

geographic model of speciation is allopatric model:

  • occurs either through dispersal –> original population dispersing to a … (e.g. island, new region being colonized)
  • or through vicariance –> formation of a … that splits the distribution of the population into … such that the new species can form
A

new environment;
barrier;
two

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

geographic model of speciation is allopatric model:
- does not necessarily require … to occur in this model. It can just rely on …, which changes frequencies such that they become …

A

selection;
drift;
genetically incompatible

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

geographic model of speciation is allopatric model:

  • e.g. drosophila in Hawaii –> several species of flies and their differentiations follow the timing of the …
  • molokai and maui species are more closely related - … species
  • this is a case of …
A

formation of the islands;
sister;
dispersal

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

geographic model of speciation is allopatric model:

- geological event in the Americas –> closure of the …, which is a connection between … and …

A

isthmus;
South America;
Central

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

geographic model of speciation is allopatric model:

  • geological event in the Americas - closure of isthmus
  • resulted in … –> fauna that originated in South America and then migrated to … and fauna from North America also migrated to …
  • But some sea species became … due to the isthmus closure - this is the case of …
A 
Great American biotic interchange; 
North America; 
South America; 
isolated; 
vicariance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

speciation with adaptation:

- gradient of … across the space –> can have species adapted to different … and different …

A

different climates;
regions;
climates

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

speciation with adaptation:
gradient of different climates across the space –> can have species adapted to different regions and different climates

e. g. yellow monkeyflower
- coastal ecotype - … plant, keeps …
- inland ecotype - dies during … period and become … plant

A

perennial;
flowering;
drought;
annual

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

speciation with adaptation:

e. g. yellow monkeyflower
- coastal and inland ecotypes
- scientists transplanted species and switched their environments
- if you take inland to inland field site, a lot flower and they … - expected fitness is … compared to coastal
- if you move coastal to inland site they … as much and thus have a …

A

thrive;
very high;
don’t flower;
lower fitness

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

speciation with adaptation:

e. g. yellow monkeyflower
- if transplant inland to coastal, they … while coastal version is …
- this shows the … - adapted to different climates and it suggests that they are in a process of …

A

don’t flower;
fine;
adaptation;
speciation

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

speciation with adaptation:

e. g. yellow monkeyflower
- could be considered … at that point depending on how you define species –> if there’s gene flow they’re not …
- this is …

A

separate species;
totally reproductively isolated;
parapatric speciation

17
Q

speciation with adaptation:

  • … within the same area
  • development of two different adaptations to two different …, for example, leading to speciation –> … selection regarding bill shape in seedcracking finch - ongoing process of speciation in the same geographic area
A

divergence;
food sources;
disruptive

18
Q

speciation with adaptation:
divergence within the same area
- disruptive selection regarding bill shape in seedcracking finch
- this is …
- this differentiation within the same region is due to …

A

sympatric;

sufficient genetic polymorphism

19
Q

speciation with adaptation:

  • in both of the above cases, the isolation is not complete (i.e. … and …)
  • peripatric –> difficult to tease apart in nature, edge of a population …, … forming a new species
A

parapatric;
sympatric;
colonizing a new area;
periphery of distribution

20
Q

3 basic models of speciation:

…, …, …

A

allopatric;
parapatric;
sympatric

21
Q

There can be … and … in the case of sympatric and parapatric
- what keeps sympatric species separate - two mechanisms to prevent gene flow from homogenizing the population: … and …

A

gene flow; gene exchange;

prezygotic; postzygotic

22
Q

There can be gene flow and gene exchange in case of sympatric and parapatric. What keeps sympatric species separate:

  • prezygotic: zygotes are …, usually because … doesn’t even take place (e.g. bc of a behavioral deterrent)
  • postzygotic: hybrids are …, … or have … (e.g. crossing tiger and lion)
A 
never formed; 
mating; 
inviable; 
sterile; 
reduced fitness
23
Q 
what keeps sympatric species separate: 
when species do interbreed, 3 possible outcomes: 
- reinforcement of ...
- formation of ... with ...
- ....
A

prezygotic isolation;
new species; hybrid;
stable hybrid zones

24
Q

when species do interbreed, 3 possible outcomes:

  • reinforcement of prezygotic isolation –> offspring doesn’t have qualities to have one extreme or the other and they can’t …
  • formation of new species with hybrid –> hybrid filling a … that’s not being filled by either species, …
  • stable hybrid zones
A

attract opposite sex mate;
niche;
instantaneous

25
Q

There can be gene flow and gene exchange in case of sympatric and parapatric.
- if genetic incompatibility in hybrids, hybrids are … –> this usually happens when two species are isolated … and for some reason get into contact again (this is called …) –> might be able to mate but never have hybrids

A

never born;
for a long time;
secondary contact;

26
Q

There can be gene flow and gene exchange in case of sympatric and parapatric.

  • hybrid speciation is very common in …
  • selection can favor hybrid just in …
A

plants;

transition zone

27
Q

There can be gene flow and gene exchange in case of sympatric and parapatric.
- selection can favor hybrid just in transition zone –> hybrid adapted in specific transition from one climate to the other, for example. forms a stable … - zone that only hybrids can occupy bc they’re ….

A

hybrid zone;

better fit to the environment

28
Q

There can be gene flow and gene exchange in case of sympatric and parapatric.
- forms a stable hybrid zone: but they can never expand …, can be relatively … or … for hybrid zones

A

beyond the hybrid zone;

narrow; broad

29
Q

Little consensus when it comes to species concepts bc none work in all cases:
- oldest and most used concept is … concept –> relied on for … of species, based on … of species

A

morphospecies;
initial naming;
morphological similarities

30
Q

Little consensus when it comes to species concepts bc none work in all cases:
oldest and most used concept is morphospecies concept:
- can use this for … as well, except for if differences are by … or …
- doesn’t work for …

A

fossils;
color;
soft tissue differences;
cryptic species

31
Q

Little consensus when it comes to species concepts bc none work in all cases:
phylogenetic species concept:
- based on …
- easily testable by … –> testing and repeating process of … - more scientifically sound, can also use …

A

monophyly;
building other trees;
species description;
statistics

32
Q

Little consensus when it comes to species concepts bc none work in all cases:
phylogenetic species concept:
- problem: if you use morphology and genetics independently, they give you …
- other problem: could increase the … that we have a lot
- distinguishes cryptic species if using … to build tree

A

different phylogenetic trees;
number of species;
genetics

33
Q

Little consensus when it comes to species concepts bc none work in all cases:
biological species concept:
- widely accepted
- based in …
- uses … to describe new species
- this is the concept used in the US for … purposes

A

reproductive isolation;
complete reproductive isolation;
conservation

34
Q

Little consensus when it comes to species concepts bc none work in all cases:
biological species concept:
- key element is …
- it’s hard to apply though –> rarely can bring different species to a lab and try to … to determine if they’re …

A

lack of gene flow;
breed them;
isolated

35
Q

Little consensus when it comes to species concepts bc none work in all cases:
biological species concept:
- idea against this concept: keeping gene flow between species can actually be … –> if exchanging genes with other species, can acquire … in …

A

adaptive;
adaptive genetic material;
changing environments

Evolution (27 decks)

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