Transcript 2-357Lecture

Biology 357 – Evolutionary Ecology
Professor: Eric R. Pianka
Office: Patterson 125, Mon., Fri. 1-2 PM
471-7472, [email protected]
Course Website:
http://www.utexas.edu/courses/bio357/
Download Syllabus from above site
Please go to course website and read NY Times: “Depth of Time”
article. Also, please read Nee’s one page commentary in Nature
(downloadable pdf) and “Evolution’s Problem Gamblers”
Also read: “Scientific Methods” and “Natural Selection”
Ground Rules, exams, etc. (no “make up” exams)
Text: read chapters 1, review 2 through 7, then read 8, etc. …
Ecology, Environment, not beer cans and pollution
Anthropocentrism: what good are you?
Captive versus wild animals. Love in vials.
Pristine natural environments
Vanishing book of life, need to conserve but also to READ.
Scaling in Biology : microscopic —> macroscopic
Patience required to study ecology & evolution (also large spaces)
Reductionistic versus holistic approaches
Pianka, Evolutionary Ecology, 6th or 7th editions
You can also read these on line at Blackboard’s
“Course Documents”
Please Read
Chapter 1
Chapter 8
“Scientific Methods”
“Natural Selection”
[Also, please look over Chapters 2 through 7 to make
certain you are familiar with that background material]
Suggested Additional Reading
An Illustrated Guide
to Theoretical Ecology
Case, An Illustrated Guide to
Theoretical Ecology
(read pp. 79-100)
Gotelli, A Primer
of Ecology (read
Ted J. Case
pp. 2-85)
Ginzburg and Golenberg, Lectures in Theoretical Population
Biology (read pp. 1-5 and 193-219)
Exams:
First Exam: 26 Sept.
Second Exam: 31 Oct.
Third Exam: 5 Dec.
Final Exam: 13 December, 2-5 PM
Best 2 of 3 = 50% + Final 50%
[No “Make Up” Exams!]
Grades:
Three hour exams
26 Sept.
31 Oct.
>
Best 2 of 3 = 50%
5 Dec.
Final 50% : 13 December, 2-5 PM
+/- Grading System will be used
[No “Make Up” Exams!]
Hierarchical Organization of the Biological Sciences
<—————— Integrative Biology——————————>
Figure 1.1
Scientific Methods.
Curiosity, assume that organized reality exists
Not faith-based, but based on repeated predictable patterns
Models, Hypotheses, Theories, Simplifying Assumptions
Model: mere “caricatures of nature” (all models are imperfect)
“Laws” in Physics & Chemistry versus biology (complex, diversity)
Observation, Experiment : confront model with reality (test it)
No clean facts, no “truth” or “proof” in science
Profess —> Study : transfer of Knowledge
QuickTime™ and a
decompressor
are needed to see this picture.
Models may be verbal, graphical, or mathematical
Model: mere “caricatures of nature”
(all models are imperfect)
Trade offs in construction of m odels
precision
generality
realism
Wisdom
Knowledge
QuickTime™ and a
decompressor
are needed to see this picture.
Understanding
Manipulation
Wisdom
Knowledge
QuickTime™ and a
decompressor
are needed to see this picture.
Understanding
Manipulation
Profess: “to claim to have knowledge of”
Wisdom
Knowledge
QuickTime™ and a
decompressor
are needed to see this picture.
Understanding
Manipulation
Profess: “to claim to have knowledge of”
Study: “application of the mental faculties to
the acquisition of knowledge”
Proper motivation to do science is curiosity.
How do things work?
Assume an organized reality exists and that
objective principles can be formulated to reflect
this natural order. Not faith-based, but based on
repeated predictable events and patterns.
Common misconception that “truth”
and “proof” and even “facts” exist.
Nietzsche said “there are no facts,
only interpretation.”
Nietzsche
Sunrise
Sunset
Geocentric world view
Sunrise
Sunset
Geocentric world view
X
X
Sunrise
Sunset
Geocentric world view
“Spinup”
“Spindown”
Solar system world view
Heliocentric world view
Our One and Only Spaceship
Observation and Experiment are vital.
Scientists formulate hypotheses to explain repeatable events.
A hypothesis is tested by confronting it with reality —
if it fails, it is discarded and replaced with another, hopefully
better, hypothesis.
In time, a well supported hypothesis becomes a theory.
The scientific method is self regulating: poor hypotheses are
continually replaced with better ones as human knowledge
expands and is improved.
We benefit immensely from past genius.
A sprinkling of past geniuses:
Socrates
DaVinci
Aristotle
Newton
Archimedes
Darwin
Euclid
Einsteinn
Domain of Ecology
Simple versus multiple causality
Figure 1.2
Evolution is not synonymous with Natural Selection
Evolution is defined as any change in the gene pool
Agents of Evolution
•
Genetic Drift (random sampling)
•
Gene Flow (migration)
•
Mutation Pressure
•
Meiotic Drive
•
Natural Selection
Natural Selection = Differential Reproductive Success
“Struggle for Existence”
“Survival of the Fittest”
Selection results in Adaptation (other agents of evolution do not)
(Adaptation is conformity between organism and environment)
Natural Selection does not always
operate via Differential Mortality
Cautious long-lived tomcat
versus short-lived alley cat
Natural Selection does not always
operate via Differential Mortality
Cautious long-lived tomcat
versus short-lived alley cat
The currency of Natural Selection
is progeny (offspring, babies)
Natural Selection does not always
operate via Differential Mortality
Cautious long-lived tomcat
versus short-lived alley cat
The currency of Natural Selection
is progeny (offspring, babies)
Not beauty, brains, or brawn
If the ugly stupid and weak make
more babies, their genes prevail
Natural Selection does not always
operate via Differential Mortality
Cautious long-lived tomcat
versus short-lived alley cat
The currency of Natural Selection
is progeny (offspring, babies)
Not beauty, brains, or brawn
If the ugly stupid and weak make
more babies, their genes prevail
“Selfish” Genes
“outlaw genes”
meiotic drive
(segregation distortion)
Richard Dawkins
“packaging problem”
Parliament of genes
Viruses
Genes are the ultimate
Gees
replicators. Bodies are
merely giant machines
designed by genes for
their own survival.