1. BACKGROUND
• Populations are interbreeding groups; members of the same species in a particular area
• Populations are dynamic; changes due to:
natality (births)
mortality (deaths)
immigration (moving in)
emigration (moving out)

2. growth rate constant, regardless of population size
linear growth
growth rate constant, regardless of population size 25 20 15 10 5
Small or large population, growth rate stays the same

3. Linear growth is additive
EX: Assume a growth rate of 2 offspring per generation:
10 mating pairs
+2 = 12
+2 = 14
+2 = 16

4. growth rate proportionate to population size
exponential growth
growth rate proportionate to population size
Large population
rapid growth
+24,000 gen
Small population size, slow growth
+ 500 /generation
Fun fact: doubling time is the rate divided by 69. EX: 3% growth rate /69 = 23 years to double

5. Exponential multiplies
Assume a growth rate of 2 offspring per mating pair
10 mating pairs
+20 = 30
+60 = 90
+180 = 270

6. Analogy – Making the most out of saving $
As the ‘pot’ increases, so does the rate of growth
Size of savings account has no impact on rate

7. Which describes populations?
populations have great biotic potential
because they experience exponential growth