ECOLGEN LE2 REVIEWER
Lecture 1
Explanations for Ecological Phenomena
1. Proximate Explanation
The immediate cause of the phenomenon
Birds lay fewer eggs, have smaller clutches during times of food
scarcity
Temperature, day length, moonlight intensity, time after sunset
Ultimate explanations
2. Ultimate Explanation
More general reason; rooted in evolutionary theory
Seasonal temperature cycles that may optimize physiological
performance for sexual reproduction in corals, wind speeds and tidal
phases that may maximize fertilization success and dispersal, and
diurnal cycles that may allow for predator avoidance (Randall et al.
2020)
Evolution and Adaptation
1. Evolution
In its broadest sense, is genetic change in a population of organisms over time
Organism's ecological situation directs its evolution
The organism's response to its ecological situation may be evolutionary
The basic evolutionary unit is a population a group of conspecifics (members of the
same species) inhabiting a specified geographic area
Example: Pokemon does not evolve biologically because biological evolution
states that there should be a change in a collection of individuals (population). It
also takes years for smth of biological evolution to do so.. and pokemon only
requires one episode (20 min lol)
ECOLGEN
This study sourceLE2 REVIEWER
was downloaded by 100000899606070 from CourseHero.com on 02-22-2026 02:51:18 GMT -06:00 1
https://www.coursehero.com/file/155888034/ECOLGEN-LE2-REVIEWERpdf/
, Biological evolution involves a change in the genetic makeup
2. Adaptation
A genetically determined characteristic (whether behavioral, morphological, or
physiological) that improves an organism's ability to survive and reproduce in a
particular environment.
An evolutionary process whereby organisms become better suited to their
environments
Lecture 2
Evolution in Population
Hardy-Weinberg Theorem
Mathematical algorithm that allows us to detect and measure genetic change.
Genetic change that might be the result of evolution.
Assume diploid organism polymorphic for A (A,a) with following genotype frequency
AA 30 individuals (30/100) = 0.3
Aa 20 individuals (20/100) = 0.2
aa 50 individuals (50/100) = 0.5
0.3 AA + 0.2 Aa + 0.5 aa = 1
Allele Frequency for A:
p = (30 + 30 + 20)/200 = 0.40 or (0.3 + 0.3 + 0.2)/2 = 0.4
Divided by 200 because an individual produces 2 alleles
Allele Frequency for a:
q = (50 + 50 + 20)/200 = 0.60 or (0.5 + 0.5 + 0.2)/2 = 0.6
Paired combinations of matings are then (female x male)
Female Gametes Male Gametes Zygotic Frequencies
0.40 A 0.40 A 0.16 AA
0.40 A 0.60 a 0.24 Aa
0.60 a 0.40 A 0.24 Aa
ECOLGEN
This study sourceLE2 REVIEWER
was downloaded by 100000899606070 from CourseHero.com on 02-22-2026 02:51:18 GMT -06:00 2
https://www.coursehero.com/file/155888034/ECOLGEN-LE2-REVIEWERpdf/
Lecture 1
Explanations for Ecological Phenomena
1. Proximate Explanation
The immediate cause of the phenomenon
Birds lay fewer eggs, have smaller clutches during times of food
scarcity
Temperature, day length, moonlight intensity, time after sunset
Ultimate explanations
2. Ultimate Explanation
More general reason; rooted in evolutionary theory
Seasonal temperature cycles that may optimize physiological
performance for sexual reproduction in corals, wind speeds and tidal
phases that may maximize fertilization success and dispersal, and
diurnal cycles that may allow for predator avoidance (Randall et al.
2020)
Evolution and Adaptation
1. Evolution
In its broadest sense, is genetic change in a population of organisms over time
Organism's ecological situation directs its evolution
The organism's response to its ecological situation may be evolutionary
The basic evolutionary unit is a population a group of conspecifics (members of the
same species) inhabiting a specified geographic area
Example: Pokemon does not evolve biologically because biological evolution
states that there should be a change in a collection of individuals (population). It
also takes years for smth of biological evolution to do so.. and pokemon only
requires one episode (20 min lol)
ECOLGEN
This study sourceLE2 REVIEWER
was downloaded by 100000899606070 from CourseHero.com on 02-22-2026 02:51:18 GMT -06:00 1
https://www.coursehero.com/file/155888034/ECOLGEN-LE2-REVIEWERpdf/
, Biological evolution involves a change in the genetic makeup
2. Adaptation
A genetically determined characteristic (whether behavioral, morphological, or
physiological) that improves an organism's ability to survive and reproduce in a
particular environment.
An evolutionary process whereby organisms become better suited to their
environments
Lecture 2
Evolution in Population
Hardy-Weinberg Theorem
Mathematical algorithm that allows us to detect and measure genetic change.
Genetic change that might be the result of evolution.
Assume diploid organism polymorphic for A (A,a) with following genotype frequency
AA 30 individuals (30/100) = 0.3
Aa 20 individuals (20/100) = 0.2
aa 50 individuals (50/100) = 0.5
0.3 AA + 0.2 Aa + 0.5 aa = 1
Allele Frequency for A:
p = (30 + 30 + 20)/200 = 0.40 or (0.3 + 0.3 + 0.2)/2 = 0.4
Divided by 200 because an individual produces 2 alleles
Allele Frequency for a:
q = (50 + 50 + 20)/200 = 0.60 or (0.5 + 0.5 + 0.2)/2 = 0.6
Paired combinations of matings are then (female x male)
Female Gametes Male Gametes Zygotic Frequencies
0.40 A 0.40 A 0.16 AA
0.40 A 0.60 a 0.24 Aa
0.60 a 0.40 A 0.24 Aa
ECOLGEN
This study sourceLE2 REVIEWER
was downloaded by 100000899606070 from CourseHero.com on 02-22-2026 02:51:18 GMT -06:00 2
https://www.coursehero.com/file/155888034/ECOLGEN-LE2-REVIEWERpdf/
