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Flashcards in Population Growth Deck (31)
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1

Reindeer on St. Paul Island

-Important food source
-population increased exponentially
-eventually population plummeted

2

What do you need to understand to predict a collapse?

-population growth
-density dependence
-resource exploitation
-stochastic events

3

birth rate

number of young born per female

4

fecundity

table of birthrates for females of different ages

5

Annual plants: what are they, which one did we study, and what type of population growth do they have?

-Annual plants live for one year
-we studied phlox drummondii
-They demonstrate geometric growth

6

Geometric rate of increase equation

future population / current population

7

R0 (net production rate)

-growth rate per generation
-in annual plants its the same as the rate of increase
-normally it is Ixmx

8

Exponential population growth

-overlapping generations
-unlimited environment
-constant rate
-usually when a population is coming to a new area for the first time

9

Exponential growth formula for current population

N0e^rt

10

r

intrinsic rate of increase

11

Net population growth (R)

r(change in t)N

12

change in population right now

rN

13

Scott's pine

-growth seen in pollen accumulation in lakes
-after colonization, experienced exponential growth for 500 years

14

Whooping crane

-after federal protection, they experienced exponential growth

15

Elephants in Kruger park, south africa

-grew at exponential rate after hunting was banned
-not necessarily a good thing. Large mammals tend to reach a peak and then plummet when they grow like this

16

Collared dove

-had new habitat
-grew exponentially at first
-rate of growth started decreasing
-most likely bc of density dependence

17

Density independant growth

growth set by fixed parameters (R, r, or gamma)

18

density independent factors

fires, floods, tornados, etc...

19

Density dependent growth

assumes limiting factor in the environment

20

density dependent factors

food, water, nest sites, disease

21

logistic population growth

for populations that are density dependent
-S curve

22

K (carrying capacity)

the limit to the population that an environment can sustain
-birth and death rates at this number will even each other out

23

equation for current logistic growth

rN(K-N)/K

24

Demography

The study of all these statistics and how they change in a population over time

25

Survivorship curve

Shows log of survival rate at different ages

26

Types of survivorship curves

1. Tend to die when they're old
2.Constant rate of death throughout life
3. Tend to die when they're young

27

Age structure diagrams

show history of survival, reproduction, and growth
-blue on bottom, tan in middle, red on top
-steeper pyramid means faster growth

28

White oaks

biased towards young trees
-must be sufficient reproduction for replacement

29

Rio Grande Cottonwood

-old trees weren't being replaced
-no floods = fewer germination areas

30

life table

age specific summary of survival and reproduction rate within a population
-usually follows a cohort