Discussion of sea turtle pop. matrix model paperBio 41E (Karnovsky) guest lecture,Jason Price, PhD2011-03-23
3 part approach: ① Overview/Main Results & Conclusions
② Key details (Figures & Tables)
③ Big picture: Contribution to the field
Crouse et al. 1987
Part 1 Breakout: Paper overview
① What were the authors’ goals?
② What methods did they use?
③ What were the main results?
④ What did they conclude?
Crouse et al. 1987
Part 2Key Details: Parameters pg 1415
when λm = er = 1, r = 0 = stable pop. Size
ε= elasticity = Proportional senistivity =
differentialΔλfor same amnt of Δ in parameter Parameters Fi = reproductive output (think Fecundity) Gi = prop. of indiv Growing to next stage Pi = prop. of indiv surviving within stage (Di = prop of indiv. Not surviving)
pi = annual survival probablility di = stage duration
Crouse et al. 1987
Key Details: Stage Class Pop Matrix
0% 0 0 0 127 4 80
67% 73%
5% 66%
1% 69%
5% 0%
81% 0%
81% 81%
Crouse et al. 1987
Pg 1415
Fig 1
Crouse et al. 1987
How do they improve on Fig 1?
Crouse et al. 1987
Fig 3 Fi Pi Gi Proportional sensitivityCrouse et al. 1987
Within-stage Survival
Fecundity
Between-stage survival
How improve on Fig 3?
Crouse et al. 1987
Crouse et al. 1987
To stage specificsurvival probability
To changes in stage duration
Fig 4 pi di Proportional sensitivity
What other key details did you notice?
Crouse et al. 1987
Part 3 Big Picture What did you learn (beyond main results)?
What is the value of using life tables?
Why were you assigned this paper? / What makes it exceptional?
What question would you ask Crouse if you had been present at her PhD defense?
Crouse et al. 1987