Transcript Introduction to Ecology

Ecology 03-55-210
Fall 2006
First the nuts and bolts:
Course Outline Summary
-
Lectures:
Tuesday & Thursday 1-2:20 PM
Room 1120 Erie Hall
(but you’re here already)
Professor:
Dr. I. Michael Weis
Room 202 Biology Building
phone: ext. 2724
e-mail: [email protected]
Exam Schedule and Grade Component Weighting
1st mid-term
October 12
2nd mid-termNovember 9
12.5% of grade
12.5% of grade
In class ‘clicker’ questions
10% of grade
Lab quizzes
20% of grade
Final Exam
Dec. 13, 2006
3:30 PM
45% of grade
Required Texts
Ricklefs, R.E. 2001. The Economy of Nature 5th ed.
W.H. Freeman. New York,N.Y.
Alstad, D. 2001. Populus, Models of Ecology.
Required Supplies
Ecology Supplement – from Document Services
A ‘clicker’ – from the University Bookstore
All further information about the course is presented in
the Ecology Supplement. The supplement also provides
examples, graphical information covered in lecture, and
problems to permit you to practice the kinds of
questions you may see in the examinations.
Ecology Labs will occur Mondays in two hour blocks –
all in the Biology Learning Centre:
Section 51…………….8:30 – 10:20 AM
52……………..10:30 AM – 12:20 PM
53……………..12:30 – 2:20 PM
54……………..2:30 – 4:20 PM
55……………..4:30 – 6:20 PM
56……………..6:30 – 8:20 PM
Please make sure you go to the right place at the right
time!
Lecture Topics and Approximate Schedule
(This is an approximate list by week. There is more detail in
the handout (correct dates) and supplement (incorrect dates)
Week of
Reading
Sept. 7
Introduction– History of the subject Chap.1
Sept. 12
Adaptations of Individuals,
Chap.9,11
Sex and Evolution
Sept. 19
Territoriality and Mating Systems,
Chap.12,13
Structure of populations
Sept. 26
Demography: fecundity, mortality, Chap.14
methods of calculation
Oct. 3
Population dynamics
Chap.14,15
Oct. 10
Density dependence and
Chap.14
independence
Oct. 17
Patterns in life histories,
Chap.10
conservation and harvesting
Oct. 24
Oct. 31
Nov. 7
Nov. 14
Nov. 21
Nov. 28
Dec. 5
Intro to Community Ecology,
Chap.17,18
Predator-prey interactions
Competition between species:
Chap.19
theory and experiments
Coevolution,
Chap.20-22
Effects of interactions on communities
Species diversity:
Chap.23
patterns and causal hypotheses
Geographical Ecology
Chap.24
Biodiversity:
Chap.25
extinction and colonization
Applied ecology
Chap.26
Laboratory Schedule
See the supplement.
An introduction to the laboratory and a first assignment will be
given in lab next Monday (Sept. 11).
One Last ‘nut or bolt’
The university has adopted a new approach to course
evaluation. The questionnaire is now longer, and asks you
directly about expectations, etc. Here is a quick look at the
new form. Keep it in mind as the semester progresses.
Student Evaluation of Teaching Form
Course: _ _-_ _-_ _ _
Section: _ _
Instructor: ________________________
Instructions: Please note that the results of this evaluation will be available to the instructor
only AFTER final course grades have been submitted.
The results may be used by:
STUDENTS for aid in course selection;
INSTRUCTORS for feedback on teaching;
ADMINISTRATORS for decisions on career advancement for instructors and for program
planning.
Please complete the evaluation form honestly and seriously!
Please respond to the statements below for your instructor and then for the course, bearing in mind
that there are wide variations in class size and subject matter at the University of Windsor.
(If the statement is not applicable in this course, please mark the “NA” column.)
A.
The instructor...extremely poor(1) very poor(2) poor(3) adequate(4) good(5) very
good(6) out-standing(7) NA(0)
1. presented material in an organized, well-planned manner
2. used instructional time well
3. explained content clearly with appropriate use of examples
4. was a clear and effective speaker
5. communicated enthusiasm and interest in the course material
6. stimulated your interest in the subject and motivated your learning
7. attended to students’ questions and answered them clearly and effectively
8. was open to students’ comments and suggestions
9. was sensitive to students’ difficulties
10. was approachable for additional help
11. was accessible to students for individual consultation (in office hours, after class, opendoor, by e-mail, phone)
12. The overall effectiveness of the instructor was
Rate the course:extremely poor very poor poor adequate good very good out-standing
NA
1. How effective was the course outline in communicating goals and requirements of the
course?
2. How consistently did the stated course goals match what was being taught in the course?
3. How appropriate was the course format for the subject matter?
4. How well did the methods of evaluation (e.g., papers, assignments, tests etc) reflect the
subject matter?
5. How fair was the grading of student work?
6. How timely was the grading of student work?
7. How helpful were comments and feedback on student work?
8. How well did the instructional materials (readings, audio-visual materials, etc)
facilitate your learning?
9. How well did the instructional activities (lectures, labs, tutorials, practica, field trips etc)
facilitate your learning?
10.How reasonable was the level of difficulty of the course material?
11. How reasonable was the volume of the work required in the course?
12.The value of the overall learning experience was
13.Your level of enthusiasm for taking this course at the time of initial registration:
 low
 medium
 high
14.Your level of enthusiasm for the course at the conclusion of the course:
 low
 medium
 high
15.Considering your experience with this course, would you recommend it to
other students?
 Yes
No
C.
Statements about yourself: This information will be used to identify student demographics
and their effect on the questionnaire results. Please answer all questions honestly and to the
best of your knowledge. Ask the facilitator for assistance, if needed.
1. Your faculty:
Arts Social Sciences Science Business Education Engineering Human Kinetics Law Nursing
Interfaculty Programs 01 02 03 04 05 06 07 08 11 13
2. Your status: Undergraduate:  1st year
 2nd year
 3rd year
 4th year
 5th year
or
 B.Ed. student (Fac. of Educ.)
 Graduate student (Master’s or Ph.D. level)
3.
4.
5.
 Law
 other
Status of this course for you:
 required
Your expected grade level in this course:
 A
You are:
 Female
 Male
 not required
B
C
D
F
What is Ecology?
Ecology is the study of the distributions and abundances of
species, and the causes underlying those observed distributions
and abundances.
How do ecologists study distribution and abundance?
1) Empirical observations in the laboratory or in the field.
2) Simulation models
Direct observations are obviously realistic, but take too long. This
course lasts 13 weeks, but processes and organism life cycles may
take years. We can compare current and historical data to learn about
whether species characteristics have changed, when needed data are
available. However, many such studies are also expensive, and due
to natural environmental variation, they often fail.
You will gather four types of empirical data in labs:
• Information from “lonely hearts” ads to test some hypotheses
about the evolution of mate choice
• Historical data on birth year and length of life from cemetary
(headstone) data
• Effects of leaf extracts on germination of lettuce seeds to test for
allelopathy
• Information about waste generated and energy use in your home
Otherwise, simulation models are cheap, fast to run, make it easy
to test alternative conditions, and can give better insight into how
ecological systems work and how factors affect processes.
You will use a set of models collectively called Populus. The
laboratories using a computer modeling approach will use
four models:
• 2 that model population growth
• 1 that models predator-prey interactions
• 1 that models competition between 2 species utilizing the
same resources
Why should you study ecology?
It’s a required core course in Biological Science.
(dumb answer!)
It provides vital information that can help us understand
the world around us and conserve species and resources
for future generations.
For example, understanding extinction.
Humans are driving a rate of extinction that parallels or
may exceed rates seen during the last mass extinction 65
million years ago. But are we wholly responsible?
Why do species become extinct?
•
•
Habitat destruction
Excess harvesting
These are obvious, but only partially correct.
In the history of life on earth, more than 99.9% of species
that have lived on earth are now extinct. Most of these
extinctions occurred before humans evolved, and only a
fraction of the extinctions in recent times are directly the
result of human activity. Even then, humans probably only
dealt the final blow.
The risk of extinction is related to …
• population size
• ability to colonize new suitable sites
• reproductive potential
These are the biological conditions. How do they relate to
the impacts of humans?
Humans destroy or damage areas of habitat. In the process
areas of suitable habitat become fragmented.
Why does habitat fragmentation cause a reduction in
biological diversity? The reasons lie in the effects on
those biological characteristics…
• small fragments only support small populations.
• Those populations are more likely to become extinct,
either due to random chance or failure of reproduction.
Locally, we have dramatic evidence of another human
activity that impacts extinction…
International trade, particularly large ships that move goods
from eastern Europe (the Ponto-Caspian region) used to dump
ballast water taken up there in the Great Lakes. That water
included exotic (non-native) species. Among them the zebra mussel and small crustacean zooplankton.
Exotic, “invading” species can drive native species
extinct.
• The zebra mussel has driven most native bivalves in the
Great Lakes and other invaded lakes extinct.
• Zooplankters like Bythotrephes and Cercopagis have
had significant impact on their communities in <10 yrs.
There are international conventions on endangered species.
The CITES treaty bans international trade in endangered
species.
Canada has recently signed an international treaty on
biological diversity (the Rio convention)… the RENEW
(REcovery of Nationally Endangered Wildlife) program
is the result.
The mandate is…
• No endangered species in Canada will be allowed to
become extinct.
• Species that are locally extinct in Canada will be
be re-introduced.
However, the enabling legislation covers only federal lands.
In Canada …
Mammals
& birds
Number of species
Amphibians
& reptiles
Plants
& lichens
Extinct
8
1
2
Endangered
19
4
23
Threatened
14
3
30
Vulnerable
39
7
29
A short history of Ecology
(The longer version is on the course website. It is a chapter
written originally for an online ecology text in development.)
The term “ecology” as we now view it was first used by
Ernst Haeckel. Haeckel was an early and ardent supporter of
Darwin's theory of evolution. In 1866,
Haeckel published General Morphology,
a genealogical tree of vertebrates, that
represented the first ordering of life
according to the principles of Darwinism.
The definition of ecology we use is
drawn from that book.
The history of ecology can, in one sense, be suggested to
begin with observations of the ancient philosophers of Egypt
and Greece. However, their observations fall into what we
would now class as "natural history".
Aristotle believed in a "scala naturae", which was a scale of
increasing complexity along which species could be ordered.
Species remain unchanging on their rungs of this ladder, and
evolution does not occur.
Quantification in "ecology" can be traced to observations
collected during the middle ages, at the time of the Black
Plague. In England, matrons in each parish acted as amateur
coroners, trying to determine the causes of death. The parish
records record the numbers of births and christenings and the
probable causes of death for each corpse on a regular and an
annual basis.
Bills of Mortality and Christening provided the data for the first
calculations of population growth rate. In 1662,
John Graunt published "Natural and Political
Observations", in which he estimated the
doubling time for the population of London
from rates of birth and death in the bills. He
established that more female babies were born
than males, as well as, on average, longer
lifespans for females. Based on religious
Estimates of the time of Adam and Eve,
there had been 87 doublings since. If that were true, the
population would have reached 1026 individuals, or about
100 million per square centimeter of habitable ground. Even
Graunt knew this could not be, that a pattern of regular
doubling could not continue indefinitely. This was the first
formal recognition of limits to growth.
Regular doubling is called exponential or
geometric increase. This term was coined
by Sir Matthew Hale in 1677. He was
made Lord Chief Justice in 1664 (the
equivalent of Chief Justice of the Supreme
Court). Clearly, his interests and ability
extended beyond the law.
William Petty, in "Another Essay in
Political Arithmetic" (1683) established
the notion of a maximum sustainable
population size we call the carrying
capacity, K. He was far better known as
an economist.
The next major step occurred about a century
later, and provided the first input to Darwin’s
creative synthesis we call the Theory of
Evolution. It was the recognition by Thomas
Malthus that it was resources limiting
population growth. That populations can grow
exponentially, but resources only in a linear
way was published in his An Essay on the
Principle of Population…
There were other key underpinnings to
Darwin’s theory: George Cuvier ‘invented’
paleology, showed species going extinct, and
suggested the great age of the earth.
George Lyell developed and established the
idea of “uniformatarianism”, the notion that
what we see happening in geology today has
been happening throughout the history of the
earth. He also persuaded Darwin to finally
publish the theory.
James Hutton found that the sedimentary rock
of the earth’s surface was laid down in a
sequence of layers, which reinforced ideas
about the age of the earth, and explained some
of Darwin’s observations on the slopes of the
Andes.
Putting all this together, Darwin hypothesized Natural Selection.
The final impetus for Darwin to publish came from the
independent development of the same basic hypothesis by
Alfred Russell Wallace. He collected
insects, first in the Amazon basin, then
in Indonesia. The paper that he
developed from those collections was
On the Tendency of Varieties to Depart
Indefinitely from the Original Type.
That wasn’t all he did. He also was the
first to develop what we now call
Biogeography. He is horribly underappreciated in the history of our subject.
To get further, there had to be developments in genetics.
In genetics the basic figures are well-known: Gregor Mendel,
and then to understand the importance of sex and sex
chromosomes, Thomas Hunt Morgan. Morgan
won a Nobel Prize for establishing the
chromosomal mechanism of inheritance in
fruit flies.
Mathematical models used in ecology
developed quite independently of the
basic biology. The logistic was developed
by a French mathematician, Pierre
Verhulst, but was not accepted until early
in the 20th century.
It was not Verhulst who brought the logistic into ecology, but
A demographer, Raymond Pearl, studying the history of
population growth in the U.S. To create a model (an equation)
fitting the growth pattern, he re-discovered Verhulst’s logistic.
We now have most of the basics of
ecological thought established, but there
is one more person to mention. He is
G. Evelyn Hutchinson. It is Hutchinson
whose ideas are key to a modern view
of community ecology. He’s the one
responsible for our modern view of the
niche, by means of whch we learn how
species fit together in communities. So,
in his honor, one last picture…
The ecologists in the Biological
Sciences Dept. were mostly aquatic in
orientation (now there are about as
many behavioural scientists).
Hutchinson wrote the
seminal, 3-volume work, A Treatise
on Limnology, that is, at some level,
the basis for most of the aquatic
ecologists’ work.
Scientists also have fun with
intellectual pedigrees – he’s my
intellectual great grandfather.