Population growth is determined by biotic potential, which promotes positive growth through intrinsic factors like litter size and gestation, and environmental resistance, which limits growth through extrinsic factors such as weather and food supply. Populations can experience exponential or logistic growth patterns depending on available resources. Limiting factors that influence population size can be density-dependent, like competition and disease, or density-independent, such as weather events. Over time, natural selection causes populations to adapt as limiting factors place stress on populations and favor the survival of the best adapted organisms.

1. Population Growth
Biotic Potential=
-promotes positive growth
-intrinsic factors(litter size, gestation)
Environmental Resistance=
-limits growth
-extrinsic factor(weather, food supply)

2. Patterns of growth
Exponential growth (J shaped curve)
• biotic potential(rm)=maximum value

3. Logistic growth (S shaped)
K=carrying capacity=population size that is
based on number of resources available

4. Limiting factors:
Density dependent:
-competition
-disease
-predation
-food
Density independent:
-weather
-catastrophes

5. Natural Selection:
• limiting factors place
stresses on a population
• the best adapted organisms
will survive and get to
reproduce and pass on their
genes with the adaptation
to their offspring
• over long periods of time
this can lead to a change in
species

6. Population Growth
Biotic Potential=
-promotes positive growth
-intrinsic factors(litter size, gestation)
Environmental Resistance=
-limits growth
-extrinsic factor(weather, food supply)

7. Patterns of growth
Exponential growth (J shaped curve)
• biotic potential(rm)=maximum value

8. Logistic growth (S shaped)
K=carrying capacity=population size that is
based on number of resources available

9. Limiting factors:
Density dependent:
-competition
-disease
-predation
-food
Density independent:
-weather
-catastrophes

10. Natural Selection:
• limiting factors place
stresses on a population
• the best adapted organisms
will survive and get to
reproduce and pass on their
genes with the adaptation
to their offspring
• over long periods of time
this can lead to a change in
species

11. • proportionally massive eyes
making vision acute for locating
prey
• movable ears for better hearing
making them good nocturnal
hunters
• can rotate their heads a full 180
degrees to help them avoid
predators such as wild cats
• Long back legs to help them
jump twenty feet, an important
survival skill in the jungle
• Long tail providing power for
jumping and holding onto tree
Ex:Phillipine Tarsier

12. Survivorship curves:
-based on a cohort of individuals from birth until
death
-cohort=a group of individuals of the same age
-survivorship curves are meant to show the
number of individuals surviving at each age
for a particular species
-three types of curves

13. Type 1=good early survival, die of old age, low
birth rates, provide lots of parental care
(humans)
Type 2=die at constant rate regardless of age
(birds, lizards)
Type3 =poor early survival,
survival thatimproves with
age, lots of offspring, low
parental care
(fish,plants)

14. Life History Patterns:
r selected species: species inhabiting fluctuating
or unpredictable environments-environments
keep populations below carrying capacity (lots
of predation, competition over resources)
k selected species-species inhabiting
stable, predictable environments-keep
population size near carrying capacity and
resources are scarce