|
Special Topics
|
 |
|---|
|
Special Topics
|
|
|---|
This change was implemented in the past academic year in response to the deployment of the new course "Introduction to Evolution" Biology 286a, which is a mandatory course for all students starting in Biology Programs following that time.
It is to be expected that, at least in 2005-6, and perhaps in the year following too, there will be at least some students - perhaps even a majority - enrolling in Bio 441F WHO DO NOT HAVE Bio 286a IN THEIR COURSE HISTORY. Please be advised that this is not an impediment for Bio 441a, at least for this year---- all students, regardless of having done Bio 286a will find Bio 441F accessible..
HOWEVER, the new existence of Biology 286a has had implications for the content of Biology 441F: originally, Bio 441F provided a survey of the field of evolutionary biology, filling much the same function as Bio 286a now serves. With Bio 286a in place, it is appropriate that Bio 441F will soon evolve into a higher-level consideration of a limited number of special topics. This change is reflected in the change of its name from "Evolution" to "Special Topics in Evolution".
BUT, since, as we have noted, some students will NOT have taken Bio 286a, for this coming year (2005-6) Biology 441F will retain its traditional structure as a survey course, as described below.
The present document provides an overview of the design and style of the course.
Its contents include:
Other linked documents relating directly to Bio 441a include:
| Charles Darwin in his 40s. The hero of our tale. |
Links to pages elsewhere which are of interest to students of evolution
Content:
An explanation of evolutionary phenomena is comprehensively provided
by three factors:
1. chance events and contingent circumstances, meaning anything which is unpredictable from present conditions - such factors as gene mutations to unpredictable encounters among taxa & biotas during earth's history;
2. deterministic processes, especially natural selection, acting upon any variation shown by the populations facing current conditions; and
3. the constraints of a unique history - the particular heritage of any given population, reflecting phylogeny and all other antecedent circumstances - the set of the stage at time zero, so to speak.
It is the goal of modern evolutionary studies to apportion explanation among these three factors: chance, determinism, and a unique, contingent, history.
The interplay of these sources of causation will be investigated through examining phenomena at various levels of the evolutionary hierarchy: diversity among individuals in populations; change within species through time (anagenesis); diversification of species (cladogenesis); biotic diversity; extinction & macroevolutionary change.
In so doing, consideration will be given to: the nature, analysis and explanation of adaptation; the "targets" of selection- 'selfish genes', individuals, groups, species; the nature of species and speciation; the importance of taxonomy & phylogeny; major phenomena in life's historical narrative - the development of the biota.
The vehicle for our study of this material is: Evolution by Mark Ridley, first published in 1993 by Blackwell Scientific Publications. Each week, the class will read set sections of this text prior to its discussion in the lecture periods of the week following.
NOTE: Some students will already have Freeman & Herron's Evolutionary Analysis either from Bio 366b or Bio 286a. This text is fine for Bio 441a - you do not need to buy Ridley's Evolution as well. See below for a correspondence between the chapters of Ridley and Freeman & Herron.
Laboratory:
The laboratory will feature discussions and demonstrations. Students
will be required to make oral discussion of scientific papers and respond
to quiz questions. Attendance & participation will be assessed.
Evaluation:
Evaluation is based upon the lab. discussion sessions and quizzes (20%),
and on a term paper and final examination, each worth 40%.
An excellent informal preparation for this course is to read, slowly, sometime during the preceding summer, Richard Dawkins' excellent book"Blind Watchmaker" (1986; Longman, or Penguin, or Norton.)
Dawkins has also written several other extremely valuable (and eminently readable) books in an evolutionary vein, any of which would be worth looking at. These include:
The Selfish Gene (Oxford U. P. - get the New 1989 edition - it has lots of very valuable extra discussions) is a description of the 'gene-as-unit-of-selection' viewpoint for examining evolutionary phenomena; such a viewpoint is indispensible to a modern student of evolutionary biology.
The Extended Phenotype (Freeman 1982) is a more technical and advanced discussion of ramifications of the 'selfish gene' view of evolutionary processes. River Out of Eden (Basic Books 1995), develops a world-view based on the idea that life is a proliferating system of digital information replication
Climbing Mount Improbable, was published (1997), and his most recent book, The Ancestor's Tale, was published in 2004.
In 1999, Steve Jones published an engaging book called Darwin's Ghost. It is essentially an update of Darwin's Origin: the book that Darwin perhaps might have written if he had had modern discoveries to hand to help argue his case. This book is very readable and stuffed with entertaining and useful examples.
The use of a course text makes it possible to gain that first familiarity
with the material - to have a first engagement with it - and the lecture
room provides a good opportunity for its review and discussion . This course
is organised around Mark Ridley's text "Evolution," first published in
1993, now in its second edition (1997). It covers an appropriate range
of material, it organizes it well, and it makes most of what I feel to
be the right emphases. Each week, it will be your responsibility to read
a set chapter from the text to facilitate your involvement in discussion
of the materials in the lecture sessions of the following week.
Part 2 concerns evolutionary genetics. Again, I am assuming you have some familiarity with this sort of material. It is the subject matter of Biology 366b : Evolutionary Genetics, which is required for entry into the Ecology & Evolution Honours Program, and strongly recommended as preparation for all in this course.
Parts 3, 4 & 5 contain the chapters (11-23) which are our primary concern in this course. The schedule is simple: you read chapter 11 in week 1; we review and discuss it in week 2, while you are reading chapter 12; we discuss chapter 12 in week 3, and so on.............. to chapter 23 in week 13 (we skip Chapter 19, which covers basic information on the fossil record.
To go directly to synopses of Chapters 11 to 23 click here
Throughout, you should be taking real care to ask yourself, as you go along, if you comprehend the individual bits and pieces (whether they be descriptions of concepts or of illustrative studies) and if you see how the ideas relate to one another, and to the bigger picture. This is what I mean by actively engaging the material. Could you explain it to your mum? If not, then there's a question to be asked in class. But what is that "bigger picture?" Figuring out the answer to that is one of your main tasks in this course. In your reading and in class, then, you should try to develop (or enhance) the habit of exercising your curiosity - asking questions - and the first person to ask is yourself: "Do I get the point here?" Here follows some guidance to help you take a grip on this material, which should firm up as we progress.
1. How did there come to be so many different sorts of organisms? -the Q. of origins of organismal diversity.These are both truly enormous questions, and each has many facets. Number One is especially rich.2. How did those organisms come to be so well-suited to their circumstances? -the Q. of adaptation.
1a. How do taxa originate? how do they diversify? -the Q. of speciation & diversification.And considering Number Two, we may ask:1b. Why is it that organisms can be arranged systematically according to degrees of organic resemblance so as to give
a natural nested hierarchy of relationships? -the Q. of natural classification.1c. Why are organisms distributed in such a strange manner about the globe, with most continents possessed of
their own distinctive assemblages? -the Q. of biogeography.1d. Why are organisms distributed through time in a non-random sequence? -the Q. of life's history.
2a. What fraction of an organism's make-up represents adaptations to environmental circumstances? Everything?
If not, how much is due to other things, and what are they? Is the fraction variable?2b. Are these adaptations perfect? If so, how come? If not, why not? How could we know?
2c. What are adaptations for? What entity benefits? How?
Even these sub-questions themselves involve complex issues,
and they are often very tricky matters both to specify and to approach.
Accordingly, we don't have anything like definitive answers to many of
them, though we often do have several competing hypotheses for evaluation.
Evolutionary biology is thus typified by controversy, much of which Ridley introduces in the manner: "..... on the one hand....... but then, on the other....." This, I am afraid, is simply the nature of evolutionary science - you can't just learn "the facts" in order to know evolutionary biology. Not that there aren't lots of facts - but it's their meaning that is so often problematic. Nature teems with millions of organisms, in millions of space/time situations (all organisms have a here-and-now, and they also have a long history of heres and nows), and it isn't always immediately obvious which aspects of any of it are of general, global significance, and which are only of local, contingent, meaning. Taxa just aren't like gas molecules - they all have real individuality and real histories that can affect both their immediate present and their possible futures. This is partly why we don't have biological analogues of such as Newton's or Boyle's Laws - perhaps there even aren't such things to be discovered. This is kind of unnerving if you came into science to find certainty - but it can be exhilarating if you like puzzles.
The various segments of Ridley's book are addressed to the ways we have approached, investigated, and, to some extent, solved problems like those above. The problems are often inter-related, often in complex ways, and you should try to bear the problems, and their relationships, in mind as you read. A significant part of understanding something (as opposed to simply having heard about it) is understanding thoroughly what the question was in the first place. Knowing the answer to be "42" is only partly illuminating. So a basic tool in guiding your thinking processes while studying this book is to ask which questions are relevant to the material (& vice versa), and how the material contributes to answering them. Note also that in some of the lab sessions you will be asked to provide short, written, responses to simple questions. These questions will be of the sort which you will encounter in the Final exam .
Some signposts for the chapters follow below (and don't forget to use Ridley's point-form chapter summaries.) Another tool: actively engage your mind with the material by trying to draft a couple of exam-style questions based on the chapter's scope. Actually write them out and bring them to class; we can discuss some of them, to bring out an understanding of their various merits and limitations. You don't learn to drive just by reading about it: you have to get in a car too. Or as Pushkin said: "Man should live; not simply prepare for living!"
FROM THIS POINT, THE CHAPTERS HAVE DIFFERENT
NUMBERS IN THE TWO EDITIONS OF RIDLEY, BECAUSE A NEW CHAPTER (19)
ON THE FOSSIL RECORD HAS BEEN INSERTED INTO THESECOND EDITION (it
appeared as an Appendix in the 1st. edit.),
AND
OTHER BITS OF MATERIAL HAVE BEEN RE-ARRANGED in the last two chapters.
We begin the course with a demonstration concerning Evolutionary Convergence. As you will come to appreciate, this topic involves the point of intersection of several important themes in evolution, ones which, moreover, centre on an area of great current controversy: the relative importance of selection, chance and history in determining major features of the biota. Consideration of convergence involves us in the study of adaptation, homology, taxonomy and phylogeny - central issues indeed: it thus provides an overture for the evolutionary drama.
Making an aquaintance with the primary evolutionary research literature, and thinking about what it all might mean, is an important step along the road to becoming familiar with evolutionary science. Accordingly, we use the laboratory sessions for the discussion of a number of papers from the current evolutionary literature. Such discussions help focus thinking on particular ideas, and illustrate how contemporary scientists approach some of the problems in evolutionary biology.
Here's how it works: Each week, according to the schedule on pp.26 & 27, we look at one or two papers, chosen to illustrate aspects of the topics currently being treated in the lecture classroom. Sometimes a pair of papers will be chosen to exemplify opposing sides in an area of controversy. Our concern will be to discuss the specific content of the paper(s) - what was done, how (well) it was done, what was found, what these findings mean - and, in so doing, to consider the general intellectual import of these contributions to research in evolutionary studies.
Overall, the discussions should provide a useful sidelight on the week's
material. In order to stimulate your attention to the content of
the papers, each week you will be required to hand in a very brief (<100
words) abstract of the paper(s). During each lab. session class
members will be invited to offer their understanding of, or opinion on,
matters in, or arising from, the paper(s), ranging among the following:
Laboratory credit
There are three sources of credit for a total of 20% of the course: a) your participation, b) the written abstracts, c) pop quizzes.
a) We shall work through the class membership , soliciting responses on such matters as those outlined above. The competence of responses, together with (worthwhile!) questions or (useful!) contributions to the discussions will be assessed. The usefulness of these lab. discussion sessions to you all depends crucially on the presence of a critical mass of attendees; therefore some credit depends on your simply being there. We shall therfore have a head-count to begin each session. Attendance & contribution = 0.25 total lab. credit.
b) The initial credit for each abstract will be on a satisfactory/unsatisfactory basis; this will provide 0.5 of total lab. credit.
c) Finally, in at least some of these lab. sessions, the final 20 minutes or so will be occupied with your writing a short (half page) response to an exam-style short-answer question, such as: "What is the critical distinction between kin selection and group selection?" Think of it as a lab. quiz. These short answers will be handed in, marked, and returned the following lecture or lab. session. They will provide 0.25 of your lab. credit, and they will provide useful practice for the final.
Term papers are a very important element of this course, worth 40% of the total credit (as is the final), so it is well worth taking a bit of time to understand clearly their intended purpose and required form.
NOTE: Term papers are where you show your own understanding of a topic; this may involved quoting from the writings of others. Such quotes must be distinguished clearly from your own words; not to do so risks a charge of PLAGIARISM. Therefore please note the following UWO policy:
"Students must write their essays and assignments in their own words. Whenever students take an idea, or a passage from another author, they must acknowledge their debt both by using quotation marks where appropriate and by proper referencing such as footnotes or citations. Plagiarism is a major academic offence (see Scholastic Offence Policy in the Western Academic Calendar). The University of Western Ontario uses software for plagiarism checking. Students may be required to submit their written work in electronic form for plagiarism checking.”
An evolutionary view of biology permits the integration of many disparate elements into a coherent whole: the evolutionary process is the unifying and integrating principle of biology.
While it has been traditional to pay lip service to this assertion, it is only recently that researchers have taken it really seriously and have used an evolutionary framework to illuminate the conduct and interpretation of their research work. It is intended that, in researching and writing your term papers, you should gain an increased awareness of the coherence and power of an evolutionary world-view. Consequently, it is one of your primary tasks to try to make it clear to the reader that you have achieved something of such an awareness.
I DO NOT PRESCRIBE TOPICS but require you to come up with one for yourself through mulling over the materials you have to hand - the course overview, lab. program, official course description and the table of contents of Ridley's "Evolution", or other such text. You are given a period of time to consider possible topics; during this period you are invited to discuss alternatives with me, and eventually have a final chat with me to settle on a topic. It is very important to get this done on time!!! Intelligent choice of topic is important, too.
The next job is to do some research into your chosen topic so as to gain a good idea of the scope and nature of the material. You should use the primary literature as much as possible, though you will probably use texts and/or reviews at least to get started. You will eventually be in a position to sketch, in a one-page draft, an outline of the paper that you will eventually write. Getting this structure clear before getting mired in detail is invaluable to clear thinking and clear writing; I cannot overemphasise this. Remember that in your paper you will be trying to persuade the reader, through what you write, that you clearly understand some material that may be fairly tricky.
This draft is to be handed in. It will be returned promptly, probably with an "OK, proceed" notice; possibly with a suggestion or two.
All that remains is the writing. You should aim for the equivalent of 8-10 text pages of normal double-spaced 10-12 pt. type, exclusive of any tables, figures or bibliography. DO NOT MAKE IT LONGER! Note that I do not insist on typing; I do insist on legibility and some degree of care in eliminating typos, lousy spelling, bad syntax etc. Don't mess up your chances of persuading the reader that you understand something by writing ambiguously, incoherently etc. Look up "coherent" and "unambiguous" in a dictionary if you are not absolutely sure what is meant...............
TERM PAPER SCHEDULE for 2005
The three-hour exam has a two-part structure:
Page maintained by: Paul Handford, Zoology Department, U.W.O.
Last updated: 2004/01