1. Chapter 52 ~ Population Ecology

2. Demography: study of factors that affect growth & decline of populations
Birthrate (natality, fecundity)~ # of offspring produced
Death rate (mortality)
Immigration
Emigration
Age structure~ relative number of individuals of each age
Survivorship curve~ plot of numbers still alive at each age

3. Age structure diagrams

4. Population Growth Models
Exponential growth • idealized population in an unlimited environment (J-curve);
Logistic growth
Sigmoid (S-shaped pop. Growth curve)
carrying capacity (K): maximum population size that a particular environment can support (S-curve)

5. Sigmoid (S shaped) growth
Explain:
Exponential growth phase
Transitional phase
Plateau phase
What are limiting factors?
Any factor that sets limits to population increase.
List 3…

6. The following slides are either not in IB or are found in option G

7. Population life history “strategies”
r-selected (opportunistic)
Short maturation & lifespan
Many (small) offspring; usually 1 (early) reproduction; no parental care
High death rate
K-selected (equilibrial)
Long maturation & lifespan
Few (large) offspring; usually several (late) reproductions; extensive parental care
Low death rate
r-selected species– high repro rates, quick to mature, shorter lives
K-selected species– long life, slower to mature, parental care

8. Population limiting factors
Density-dependent factors •competition •predation •stress/crowding •waste accumulation
Density-independent factors •weather/climate
•periodic disturbances

9. p.104 regular bio book for simulation
Describe one technique used to estimate the population size of an animal species based on a capture-mark-release-method.
One method of estimating the population size of an animal species is the capture-mark-release method.
1. As many individuals of a population are caught. These individuals are marked.
2. The individuals are released back into their environment.
3. After a while, as many individuals of a population are caught in the same area again.
4. The total number is taken note of and the number of those caught which are marked
This is known as the "Lincoln Index"
The formula (n1 × n2) / n3 is then used where:
n1 = the number of individuals caught in the first trial.
n2 = the number of individuals caught in the second trial.
n3 = The number of individuals in the second trial which were marked.

10. Population characteristics
Density~ # of individuals per unit of area
-- measured by counting, sample size estimates, indirect indicators (tracks, nests etc.), mark-recapture
Dispersion~ pattern of spacing
•random~ unpredictable, patternless spacing (a) •clumped~ patchy aggregation (b) •uniform~ even spacing (c)