Below follows a set of questions suggested as useful for discussions by course participants, which were not addressed in the in-class discussion times: From: Scott Sylvester What are the possible longterm evolutionary implications of a population where density is cyclic? What criteria should be applied when deciding between a descrete are/stage structured model and a continously structured model? From: Sarah Elizabeth Cates 2nd Q: Wouter et al found that daily energy expenditure (DEE) of green iguanas didn't differ between sexes or over the course of the year. However, the 'body condition' varied because of differences in energy intake... so presumably when they were doing other stuff, such as clutching in the case of the females, there wasn't enough of the DEE left over to get enough food to maintain their body condition. Basically, I'm just wondering if the DEE is at all plastic. What would the energy budget of this, or a similar species look like under different conditions (colder, more or less available food, more or less competition, predation...?) Does anybody know of studies comparing energy budgets of conspecifics under different conditions? (e.g., on different islands, at different latitudes...) From: Amy Russell Regarding population structure studies such as the loggerhead turtle paper: If you as a researcher had the option to do either, would it be more valuable to collect data over a shorter time span (say, 2-5 years) or a longer time span (10-20 years). In other words, do the statistical tests that have been developed for projecting such data make the extra time spent on a long-term study unjustifiable? From: David Bishop 1. Many papers project population size for a species for some time in the future. Are any projections made in the past coming true at the present time? How accurate are the models? From: Leah Gibbons In the Chapin III, et al. paper in Bioscience, the authors state that "if plants compensate perfectly for resource imbalance in the environment, growth should be equally limited by all resources" (p. 54). I do not understand this. If, for example, carbon and phosphorous are in abundance but nitrogen is at a level below the maximum that can be assimilated by the plant for maximal growth, is growth not limited by nitrogen but not carbon and phosphorous? Wouldn't resources that are available at a lower abundance, relative to the plant's needs for maximal growth, be more limiting than resources that are available at higher abundances (assuming, of course, the plant can assimilate all the resources it needs to). The resources would not be limiting to the same extent because their relative abundances would be different. From: Tadashi Fukami Neither Crowder et al. (1994) nor Olmsted and Alvarez-Buylla (1995) incorporated year-to-year stochastic variation in their matrix models, but such variation seems important in the populations they studied. For conservation purposes, how useful can these models without stochasticity be?