FORESTS 2018, QUESTIONS ONE: DUE Monday 24 September
These are open-ended questions. This will be the norm for this class. I won't generally ask explicitly for definitions or blank-filling and such -- BUT you should use the terminology and concepts we develop in class (and that are reviewed in the class notes), and your answers will be evaluated, in part, on how well you do that . Primarily, though, evaluation will be on the basis of a) how clearly and fully you address what's asked and b) how well you build your arguments.
Don't wander; suitable answers will almost always be possible in a paragraph or two of a few sentences and often less -- so it's important to thnk carefully about what, specifically, is being asked, and to keep your own answers sharply focused.
1. A
question for working with hypothesis generation and testing:
Review
notes on the ecology of Lyme disease in the notes from the
first classes. Researchers studying the Lyme disease epidemic have
offered several models (hypotheses) proposing ecological linkages in
a network of causes and effects that might regulate Lyme
disease -- either promoting or limiting its spread. They have compiled
data to assess or test some of these
hypotheses, but most have been only partially tested and some, while
plausible, remain essentially untested. Briefly (a paragraph or so -- no more!),
propose further
research focused on better understanding some part of this network of
interactions.
a) Identify and
state a research question
that's related to some part of this system, framing it as a hypothesis
you might be able to test (this could be something that's
directly suggested -- but not pursued -- in material
discussed/presented, or something that's not specifically mentioned,
but is suggested to you by that material).
b) Suggest
at
least one
testable prediction
(could be more than
one!) of
that hypothesis (“If this hypothesis is true, then we should
see....”). Make sure it's a prediction that's specific to that
hypothesis (i.e., are there other hypotheses that would produce the
same prediction?)
c) Suggest
a basic, plausible approach
to testing
that prediction;
this
could be pretty general and rough (“I would collect data of this sort
and see if I see the pattern predicted....”).
Refer to data-graphics or studies cited
in the class notes as
appropriate to support your research question and design. Be
concise; focus on the
essential
points.
2. Thinking about island biogeography and diversity: Recall the general relationships between colonization rate, extinction rate, island distance from a source of migrants (= isolation), and island size in shaping the "equilibrium diversity" of an island under the MacArthur-Wilson model (refer to online notes for summary; remind yourself particularly of the graphical version of the model). As we briefly discussed, other types of habitats occurring in isolated patches, surrounded by very different habitats might be island-like enough to be described by the same model. Fresh-water ponds, for example, amount to ‘islands’ of distinct habitat isolated, to some extent, in a terrestrial landscape. Thus, it might make sense to hypothesize that the MacArthur-Wilson equilibrium model would predict differences in diversity among ponds ponds for aquatic organisms. The size effect (mostly on extinction rate) seems like it would apply pretty straightforwardly. However, translation of the ‘distance (isolation) effect’ on colonization rate may require careful thought. How might you restate that part of the model to make it applicable for bodies of fresh water? Are there differences in the way you need to think about 'isolation'? What factors might influence colonization rates of aquatic organisms, and how might you express them in colonization curves as in the original M-W model? (In other words, what pond properties do you think might be most important in determining their isolation and the frequency of colonization?) Ponds host organisms of many types (algae, birds, fish, plants, many groups of insects, frogs..); some spend their entire life-cycle in the water (e.g., fish, many small invertebrates, algae), while others may be only partially aquatic (like pond turtles), or be able to move between ponds at some point in their life-cycle (like frogs, dragonflies, that are strictly aquatic as larvae, but can disperse as adults). How might your thinking about factors constraining or promoting the 'colonization curve' affect these groups differently (choose two or three to contrast)? How might this affect your predictions about diversity patterns for those groups (i.e., how would diversity patterns relate differently to degree of isolation)?