|
Information regarding the Zoology 441a Final Exam |
The
exam is entirely in essay format.
There
are three sections:
Section A: short essays
(5 marks each);
Section B:
medium-length essays (15 marks each); and
Section C: one long
essay (30 marks).
There
is choice available : please answer 8 of 11 questions
from Section A; 2 of 4 questions from Section B; and 1 of 3 questions from Section
C.
Point
form is acceptable for answers to questions in section A if it is clear and
unambiguous. Point form is not
acceptable in answers to questions in sections B and C unless information is
presented in a table. This information must be discussed in the body of the
answer.
Total
number of marks on the exam is 100.
As
stated in the first class of the year, the first question on the exam will be:
You
may still choose not to answer this question, but it’s a freebie…..
As
you study for the exam, keep in mind the format. You will be expected to demonstrate that you
can integrate concepts and put them in context, rather than just memorize a lot
of material. Thus, I will not ask you for specific examples of organisms that were discussed in lecture (e.g.
I will not ask you to describe how alarm calling in Belding’s ground squirrels
illustrates the concept of kin selection).
However, I may ask a question about kin selection, and you may choose to
include this example in your answer to illustrate your point….
You
are not responsible for specific sections of the text. The text is meant to provide background and
clarification of concepts discussed in class.
Thus, material in the text that was not covered in class will not appear
on the exam.
Papers
presented in the tutorials are also not specifically tested on the exam. However, you may choose to include
information from these papers in your answers.
I
have gone through the lecture topics and have tried to provide a context in
which to consider these topics…. I hope you will find this helpful as you
study.
1.
- why were
diversity
of life?
2. Analysis of adaptation: remember natural selection is not the only
explanation for patterns of evolution, but it is the only explanation for
adaptation!
- importance
of the comparative method (and accurate phylogenies) to
analysis of adaptation
- why has the
adaptive advantage of sexual reproduction been difficult to
demonstrate?
- how can
skewed sex ratios be considered adaptive?
3. sexual selection:
- how does it
differ from natural selection? How can it be considered to be
a “special case” of natural selection?
- what are
some of the prevailing hypotheses?
4. group and kin
selection:
- invoked in cases where the
adaptive advantage of a trait is not obvious
when
examining the benefit to an individual (e.g. reproductive
restraint)
- therefore,
the central question is: who benefits from an adaptation?
5. the ‘adaptationist programme’: an approach
to evolutionary biology that is not shared by all evolutionary biologists!
- criticisms
of the adaptationists programme – is it circular?
- are all traits adaptive (note: I
said all traits, not all adaptations)? Are there non-adaptive
explanations for some traits?
- what are
some of the constraints on adaptation?
Why are species not
necessarily
“optimally designed”?
6. evolution and
classification: why construct phylogenies at all? What is inferred in a phylogeny (e.g.
similarity indicates close descent relationships)
- what are
anagenesis and cladogenesis? How do they
interact to
produce
the characters seen in a group of related organisms?
- how do
the types of characters used in constructing a phylogeny affect
the
inferred relationships among organisms?
What leads us to
make
mistakes in constructing phylogenies (e.g. convergent evolution, mosaic
evolution etc.)?
- how do phenetecists and cladists
approach the construction of
phylogenies
differently, and what are the results?
- The concept of a species is a
fundamental assumption in our attempt to
describe the history
of evolution. Why then is it such a
slippery
concept?
- we know
that characters shared by two organisms may represent
characters
shared by descent (inheritance) or because they have
been
acquired independently by natural selection (similar
adaptations
resulting in convergence). It’s obvious
we need to
distinguish between
these two categories, but how do we do it?
- technical
considerations: outgroup analysis, the principle of parsimony,
use
of molecular data, molecular clocks etc.
7. speciation: we assume
that life on earth diversified through the process of speciation (that is, an
interbreeding group eventually becomes
two or more isolated groups, which in time, become something different from the
ancestral group). Thus, the process of
speciation is at the heart of our understanding of evolution as a process of
diversification.
- what are
some of the proposed models of speciation?
8. biogeography: the diversification of life on earth
has not occurred in a vacuum, but in space and time. Thus, processes such as continental drift,
climate change, colonization of new land masses etc. have contributed to the
pattern of cladogenesis (speciation) in evolutionary time. Furthermore, ecological considerations such
as dispersal, competition, availability of niches etc. have also shaped the
distribution of organisms.
- How do organisms expand their
range? Why do some organisms have
restricted ranges
while others are distributed around the world? What is an adaptive
radiation?
- how can
we use information about geological and geographical history to
reconstruct
the pattern of speciation in a particular taxon?
- why are
some areas species-rich while others are species-poor?
9. rates of
evolutionary change: again, evolution has a historical pattern in time. We know that some groups have diversified
much more than other groups, and that individual taxa have changed considerably
while others are relatively unchanged from their fossil ancestors.
- what are
the differences between taxonomic and phylogenetic rates of
evolution? How does an incomplete fossil record affect
interpretations
of these processes?
- how do we
analyze rates of change in single characters?
10. Punctuated equilibrium and phyletic gradualism:
The process of evolution can be viewed at a range of spatial and
temporal scales. At one end of the
scale, we know that natural selection acting on allele frequencies at each
generation results in changes in populations.
However, we know that through time evolution has also produced such
radically diverse organism as bacteria, blue whales, Tyrannosaurus rex and pine trees.
Evolutionary biologists differ in their views about the how the processes
resulting in microevolutionary changes are related to
the processes that result in macroevolutionary
changes. This has led to different
interpretations of the fossil record, but more fundamentally, signifies a
difference in view about what a species really means It’s easy to caricature extreme
positions at either end of the spectrum (everything comes down to the selection
of one allele over another vs. there is no change without speciation), but
without resorting to mud-slinging, there is an important and vigorous debate
about the processes that have written and continue to write the history of
evolution….
11. morphological change
in macroevolution: Often, we see
dramatic changes in morphology among closely related species (often, we don’t
but that’s another question for you to think about)… Up till now, we have not considered how these
changes might occur at a physiological and/or genetic level. Here we consider the processes that can give
rise to major morphological changes in a lineage…
- consider the importance of
allometry in understanding the appearance of
new features
- what
kinds of features are more likely to change than others? This
hearkens
back to the concept of constraints on adaptation (topic 5 in this list)
- what are
the different processes involved (i.e. heterochrony: types of
peramorphosis
and paedomorphosis)
- what is
the genetic basis of these types of changes
12. coevolution:
Now we consider the types of interactions
among species that can lead to evolutionary change.
- consider the ways in which species
can interact and the ways in
which
these interactions pose adaptive challenges
- can these interactions lead to
extinction? How? What kinds of patterns
may emerge?
13. mass extinctions: Be familiar with the major mass extinction
events, but put them into context of the rest of the material in the
course. What happens during mass
extinctions? What causes them? How are
they different from background extinctions? Can we tell them apart? What happens after a mass extinction? Do some species do better than others during
a mass extinction? Why?
Good
luck with your studying and feel free to contact me if you have questions….