Exam 4 Material Flashcards
(41 cards)
fecundity
Reproductive output of an individual. Low early in life, peaks in adulthood, decreases with age
Population
A group of individuals that belong to the same species and live in the same area (biotic)
Ecology
The study of how living things interact with each other and their environment (biotic & abiotic interactions)
What are the four factors that affect population size?
Birth
Immigration
Emigration
Death
What are the three patterns of dispersion?
clumped, uniform, random
life table
an age-specific summary of the survival pattern of a population
survivorship curve
Graph showing the number of survivors in different age groups for a particular species.
What are the three types of survivorship?
Type 1: Mortality happens at the end of your life (old) Ex. Humans
Type 2: Constant mortality rate, age doesn’t matter for mortality. Ex. Deer
Type 3: High number of offspring, low survival rate. Ex. Maple tree
How can molecular genetic tools can be used to study reproductive rates in the wild
- make a genetic profile of the mother
- take DNA from eggs
- Compare the genes to see how many offspring the mother had
semelparity
Reproduction in which an organism produces all of its offspring in a single event; also known as big-bang reproduction.
iteroparity
Reproduction in which adults produce offspring over many years; also known as repeated reproduction.
K-selection
- fewer offspring
- more parental care
- grow slower
- live longer
r-selection
- many offspring
- no parental care
- short lifespan
- grow quickly
Density dependence
With larger populations there are fewer resources to go around. Smaller populations have more resources
What are the factors of density dependence?
- competition for resources
- disease
- predation
- territoriality
- intrinsic factors
- toxic waste
population dynamics
The number of prey affects the number of predators and vice versa
metapopulation
a group of spatially distinct populations that are connected by occasional movements of individuals between them
What lead to the explosion of human population growth?
the human population skyrocketed after the industrial revolution. Currently there are decreased birth rates due to education and birth control
Rapid growth
More births than deaths (high rate). The majority of the population is young. Ex. Afghanistan
Slow growth
More births than deaths. Similar number of elderly and young. Ex. United States
No growth
Same number of old and young. Young replace old. Ex. Italy
What are the three subcategories of interspective competition
competitive exclusion
resource partitioning
character displacement
Ecological niche overlap
the more overlap, the more competition
competitive exclusion
Two species have an overlapping niche, fight over it, one wins and pushes the other out
