Transcript (no “make up” exams) Text: read chapters 1, 6, 7, then 3, 4, 5, 8, etc.

The Vanishing Book of Life
Can we read it?
Will we be allowed to try to read it?
Do we have time enough to read it?
Ecology requires wild organisms in the natural
environments within which they evolved and to
which they have become adapted.
Captive organisms are out of context, they don’t
have a natural environment (they might as well
be dead as far as an ecologist is concerned)
Holmes Rolston’s “Vanishing Book of Life”
Humans are just beginning to be able to read it,
but its pages are tattered and torn, and entire
chapters have been ripped out. Need to save as
much as possible (conservation biology), but also
must READ it (ecology) before it is gone.
Other organisms have a right to exist, too.
Hierarchical Organization of the Biological Sciences
Population, millions
Human population growth
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Population, millions
Human population growth
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Paul Ehrlich
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Population, millions
Human population growth
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6000
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Currently, 6.4 billion humans are using half of
Earth’s land surface, half of the fresh water,
and half of the solar energy impinging on the
surface of the Earth. Resources are NOT ever
expanding. Per capita shares are falling all the
time. 2-3 acres per person.
Growthmania economics is fundamentally flawed
Carolina Parrokeets (above)
Ivory-billed woodpecker —>
Brookesia stumpfi
Zonosaurus boettgeri
Geographic Range
of American Bison
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.
Model: mere “caricatures of nature”
(all models are imperfect)
Common misconception that “truth” and “proof”
and even “facts” exist.
Nietzsche said “there are no facts, only interpretation.”
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 from past genius.
Domain of Ecology
Simple versus multiple causality
Evolution is not synonymous with Natural Selection
Evolution is defined as any change in the gene pool
Agents of Evolution
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Genetic Drift (random sampling)
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Gene Flow (migration)
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Mutation Pressure
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Meiotic Drive
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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
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
Darwinian Fitness = ability to perpetuate genes
in the gene pool
Natural Selection operates like an efficiency expert,
ferreting out the best way to perpetuate an organism’s
genes
Natural Selection is however short sighted
(does not “see” past the next generation!)
Natural Selection is the ultimate inventor: flight,
echolocation, celestial navigation, insulation, infrared
sensors, hypodermic needles, plus all sorts of
pharmaceuticals (antibiotics, analgesics, diuretics,
hormone mimics, laxitives, tranquilizers, etc.)
Organisms are classified hierarchically
5 Kingdoms: plants, animals, fungi, protists, bacteria
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Phylum
Class
Order
Family
Genus
Species
Arthropoda
Insecta
Diptera
Drosophilidae
Drosophila
melanogaster
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Chordata
Mammalia
Primates
“Hominidae” (Pongidae)
Homo
sapiens (the “sap”)