Connell 1971 and Wauters et al. 2019

Connell 1971 and Wauters et al. 2019

Discussion Questions:

1. What do you think about Connell’s conclusions about the roles of intraspecific versus interspecific competition among the barnacle species? Do you think these results are robust/repeatable/reliable?
2. Were there any factors of Connell’s experimental design or the study organisms (two barnacles and a predatory snail – Chthamalus, Balanus, and Thais) that you felt may have adversely affected/biased his results over the course of the study?
3. Wauters et al. argue that the two plausible explanations for sociability expression seen in the red squirrels (which could both be happening) are: 1) interspecific competition drives natural selection by favoring certain personality phenotypes, and 2) observed differences in red squirrels are the result of context-dependent behavioral plasticity. Based on the study and your own research/knowledge, are you more convinced by one of these mechanisms as the explanation for their results, or perhaps an alternative? Why/why not?

Huffaker 1958 & Ong et al. 2018

Discussion Points – Dec. 2^nd Huffaker (1958) & Ong et al (2018)

·      Overall thoughts on each paper – what people liked, disliked, didn’t understand

·      Contrasting the classic paper & the modern

o  similarities and differences

o  how Ong built on & expanded Huffaker’s work

·      Connection between these experiments and previous mathematical/theoretical studies (e.g. Lotka-Volterra) regarding cyclic predator-prey dynamics in nature

o  Conclusions & applying concepts to management decisions, the impact of monoculture, etc.

o  Comparison between Huffaker’s conclusions vs. Gause’s experiments which demonstrated predator-prey species eventually reaching extinction

·      Thoughts on Ong et al’s distinction between stable & effective biological controls

·      Thoughts on Huffaker’s methods of introducing aids in dispersal and barriers/impediments to dispersal

·      Differences in how Huffaker & Ong et al created spatial heterogeneity in their experimental set-up

·      Ong et al’s conclusions regarding two biological control agents (ladybird beetles & an entomopathogenic fungus) compared to Huffaker’s experiment using only one predator species

·      At the time of Huffaker’s publication, it was a “much debated question” as to whether the “predator-prey relation is inherently self-annihilative.”

o  Is this still a debated question in ecology? 

o  Are there examples of the “self-annihilative” predator-prey dynamics in modern natural systems? 

·      Why is the lynx-hare example is more used commonly than Huffaker’s data (specifically Figure 18) as the “textbook example” for predator-prey oscillations?