1. Friday 3/7 Pop Quiz #7 Turtles and Snakes ID Quiz
Notes on population math from Chs 9 and 10
Lab 4B
Lab 4A - 15 SP only (for homework)
30 (lab 7) + 20 (PQ 7) + 15 (S&T ID) + (10 wk8Eng)
= 75!

2. Pop Quiz #7

3. Snakes begins on next slide

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14. We’ve talked about (at least) one way to determine if a population is growing?

15. Rate?

16. Rate?
Variable per time

17. Rate? Variable per time N, t N/t = rate
Individuals added per unit time = rate of growth

18. BUT, The growth rate will change in response to other variables
Like what?

19. So, Change in Rate
dN/dt

20. So, Change in Rate
dN/dt = rN

21. This is compounding dN/dt = rN
Because as N gets larger, the constant r multiples by a larger and larger number.
As population size (N) increases, the rate of increase gets larger.
The result of this compounding is an exponential growth curve. (p 243, 244, 245 Molles; p 67 Kingsolver for examples)

22. PS - Stretch it out
By plotting this same data on a logarithmic scale (10X at each increase), the line straightens out (p 68 Kingsolver)

23. In exponential growth
We can determine the population size at any time (t), by:
Nt = N0ert

24. P 244 Molles

25. Can exponential growth continue forever?

26. Can exponential growth continue forever?
Stay tuned for logarithmic (more realistic) growth models (11.2 – 11.3)

27. Lab 4B

28. For Monday Read Molles 11.2 and 11.3 Finish AA sheep
Monday is last day to withdraw from full semester courses
Exam 2 is M 3/31 – Ch 9-12
Five labs left – all field