CHAPTER 3.2 Natural Selection and Modern Synthesis

Question 1

• there is genetic variation within a population which can be —
• overproduction of offspring leads to — for survival
• individuals with beneficial adaptations are more likely to survive to pass on their genes
• over many generations, there is a change in —

Answer 1

inherited
competition
allele frequency

Question 2

Variation

• organisms inherit characteristics from both of their parents and each organisms get a different combination of features - —
• changes in characteristics of organisms as affected by their surroundings - —

Answer 2

inherited variation
environmental variation

Question 3

Fraternal twins
-develop from — of egg and sperm
-same-sex or one of each
- —- placentas

identical twins
-develop from — egg and sperm
-same sex
- — placenta

Answer 3

two sets
separate

same
shared/separate

Question 4

-product of overpopulation
-species tend to produce more offspring than the environment can support, hence, there is struggle for survival
-interaction between species over a limiting resource that negatively affects their population growth rates

Answer 4

competition

Question 5

Competition

-within one/same population, there could be fluctuations on the number of offspring
-two or more population that are competing with each other causing decrease/increase of population

Answer 5

intrapopulation oscillation
interpopulation oscillation

Question 6

-evolutionary effects of competition
-because of limited resource, the populations with the same need will compete, leading to exhaustion, separates unto different habitat. exposing to different resources - mutation

Answer 6

character displacement

Question 7

Types of Competition

Base of Taxonomical Relationship
1. same species that compete for limited resources (carrying capacity)
2. asymmetric competition, two different species (abilities) between two individuals of different species competing for the same resources
-reduction in the population of the weaker species, stronger ones survives and reproduces
-regulates ecological communities

Answer 7

intraspecific competition
interspecific competition

Question 8

types of competition

Base on Influence
1. an interaction where the species living in an ecosystem directly influence each other by affecting the availability of resources in the ecosystem
2. species influence the availability of resources indirectly, species involved usually exist in different ecological niche

Answer 8

direct competition
indirect competition

Question 9

types of competition

Base on Mechanism
3. both competing species are preyed upon by the same predator
1. directly influence the process of foraging, reproduction of others, or prevent the establishment of the species in an environment, ex. fight, steal, kill
2. species are connected by a common limiting resource that acts as an intermediate. ex. space, water

Answer 9

apparent competition
interference competition
exploitative competition

Question 10

two closely related species tend to be more distinct when they are sympatric than when they are allopatric

In allopatric speciation, — or divergence has to take place, while in sympatric speciation, — that live in the same habitat

Allopatric speciation is the most common mechanism of forming new species, while sympatric speciation is driven by genetic or sexual isolation.

Answer 10

character displacement

geographical isolation
new species evolve from one ancestral species

Question 11

-interspecific interference competition (direct competition)
-shifts in traits that affect the rate, intensity or outcome between sympatric species

-interspecific exploitative competition (indirect competition)
-shifts in traits that affect resource overlap between sympatric species

Answer 11

agonistic ACD
ecological ECD

Question 12

-adjustment of organisms to their environment in order to improve their chances at survival
-result of genes the organism inherits from its parent

Answer 12

adaptation

Question 13

— feature of an organisms’ body that helps it to survive/ reproduce ex. long neck, tough tongue
—responses made by an organism ex. 10g water intake at a time
—enzymes, chemical ex. heart thickness

Answer 13

structural adaptation
behavioral adaptation
physiological adaptation

Question 14

physical resemblance of two/more species resulting from inherent advantages of similar appearance; learned/ innates

immitative species -
species it resembles -

Answer 14

mimicry
mimic
model

Question 15

Three Fundamental Types of Mimicry

-several noxious species come to resemble each other
-benign species resembles noxious/ dangerous
-noxious/ dangerous species resembles a benign one

Answer 15

mullerian
batesian
agressive

Question 16

• environmental pressures lead to differential reproduction within a population, hence, resulting in —- of traits
• it is a process where organisms are subjected to causing changes in —
• surviving traits would be prevalent in future population species

Answer 16

selection
allele frequency/ gene pool if they are able to survive and reproduce

Question 17

• selection acts at the level of the individual and selects for individuals with greater contributions to the gene pool of the next generation
• the contribution an individual makes to the gene pool of the next generation relative to the contributions of other organisms/ individuals

Answer 17

evolutionary fitness
relative fitness

Question 18

Types of Selection

1. for moderate traits against both extremes
2. for one extreme trait against the other extreme
3. for both extremes against moderate traits
4. fitness of phenotypes is dependent on its frequency relative to other phenotypes in a given population
   a. common phenotypes in a population and decreases the genetic variance
   b. selects for rare phenotypes in a population and increases genetic variance

Answer 18

stabilizing selection
directional selection
disruptive selection
frequency-dependent selection
positive frequency-dependent selection
negative frequency

Question 19

selection pressure on males and females to obtain mates, can result in traits designed to maximize sexual success
often results in the development of secondary secual characteristics, which help to maximize a species’ reproductive success, but do not provide any survival benefits (handicap principle)
a. competition among members of same sex (usually males) for access to mates
b, members of one sex (usually females) choose members of the oppositve sex

Answer 19

sexual selection
intrasexual selection
intersexual selection