Ground Rules, exams, etc. (no

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Second Exam Thursday 2 April 2015 Covers
Chapters 5, 8, 9, and 10 Lectures 10 to 19 plus
Agriculture Global Warming The Vanishing Book
of Life on Earth Plastics Intelligent
Design? The Weakest Link Technology Economics
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Social Behavior Hermits must have lower
fitness than social individuals Clumped, random,
or dispersed (variance/mean ratio) mobility
motility vagility (sedentary sessile
organisms) Fluid versus Viscous Populations
Use of Space, Philopatry Individual
Distance, Daily Movements Home
Range Territoriality (economic
defendability) Resource in short
supply Feeding Territories Nesting
Territories Mating Territories
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Sexual Reproduction Monoecious
(Hermaphrodites) versus Diecious Evolution of
Sex gt Anisogamy Diploidy as a fail-safe
mechanism Costs of Sexual Reproduction (halves
heritability!) Facultative Sexuality (Cladocera,
Daphnia) Protandry ltgt Protogyny (Social
control) Parthenogenesis (unisexual
species) Possible advantages of sexual
reproduction include two parents can raise
twice as many progeny mix genes with desirable
genes (enhances fitness) reduced sibling
competition heterozygosity biparental origin
of many unisexual species
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Four Possible Situations Involving an
Individuals Behavior and Its Influence on a
Neighbor _________________________________________
_________________________ Neighbor(s) Gain
Neighbor(s) Lose ___________________________
_______________________________________
Individual Gains Pseudo-altruistic behavior
Selfish behavior (kin selection)
(selected for) _________________________
_________________________________________
Individual Loses True altruistic behavior
Mutually disadvanta- (counterselected)
geous behavior
(counterselected) ________________________________
_________________________________
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W. D. Hamilton (1964) Kin Selection
Inclusive Fitness Hamiltons
rule r n b c gt 0 r coefficient of
relatedness n number of relatives that
benefit b benefit received by each
recipient c cost suffered by donor r n
b gt c Adaptive Geometry of a
Selfish Herd
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Adaptive Geometry of a Selfish Herd
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Eusocial Insects Hymenoptera (thin
wings) Ants, bees, wasps, hornets
Workers are all females Haplodiploidly Isopte
ra (same wings) Termites (castes consist of
both sexes) Endosymbionts Parental
manipulation Cyclic inbreeding
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White-Fronted Bee Eaters, Kenya
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Helpers at the Nest in White-Fronted Bee Eaters
in Kenya _________________________________________
_________________________ Breeders r Number
of Cases Cases ________________________________
__________________________________ Father x
Mother 0.5 78 44.8 Father x
Stepmother 0.25 17 9.8 Mother x
Stepfather 0.25 16 9.2 Son x
Nonrelative 0.25 18 10.3 Brother x
Nonrelative 0.25 12 6.9 Grandfather
x Grandmother 0.25 5 2.9 Half
brother x Nonrelative 0.13 3
1.7 Uncle x Nonrelative 0.13 2
1.1 Grandmother x Nonrelative 0.13 1
0.6 Grandson x Nonrelative 0.13 1
0.6 Great grandfather x Nonrelative 0.13
1 0.6 Nonrelative x Nonrelative 0.0
20 11.5 Total 174 100.0 ____________
__________________________________________________
____ r coefficient of relatedness.
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Donor Recipient Small
costs, large gains, reciprocated
Sentinels Robert Trivers Biological basis
for our sense of justice? Friendship,
gratitude, sympathy, loyalty, betrayal, guilt,
dislike, revenge, trust, suspicion,
dishonesty, hypocrisy
Reciprocal Altruism (Trivers 1971)
-gt lt----
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Selfish caller Hypotheses 1. Full up I see
you 2. Mass pandemonium 3. Keep on moving 4.
Mixed species flocks, fake alarm calls
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Game Theoretic Approaches Costs versus
benefits of behaviors tit for tat strategy
can lead to cooperation (the future casts a
long shadow back on the present --
Axelrod) Evolutionarily stable strategies
ESS (a tactic that when present in a
population, cannot be beaten)
John Maynard Smith
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Game Theoretic ApproachesPrisoner's
dilemmaTwo suspects, A and B, are arrested by
the police. The police have insufficient evidence
for a conviction, and, having separated both
prisoners, each of them is offered the same deal
if one testifies for the prosecution against the
other and the other remains silent, the betrayer
goes free and the silent accomplice receives the
full 10-year sentence. If both stay silent, the
police can sentence both prisoners to only six
months in jail for a minor charge. If each
betrays the other, each will receive a two-year
sentence. Each prisoner must make the choice of
whether to betray the other or to remain silent.
But neither prisoner knows for sure what choice
the other prisoner will make. So the question
this dilemma poses is What will happen? How
will the prisoners act?
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Prisoner's Dilemma Prisoner B Stays
Silent Prisoner B Betrays Prisoner A Stays
Silent Both serve 6 months Prisoner
A serves 10 years Prisoner B goes
free Prisoner A Prisoner A goes
free Betrays Prisoner B serves 10
years Both serve two years http//plato.stanfo
rd.edu/entries/prisoner-dilemma/
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Evolution of Self Deceit Subconscious
mind Polygraph playback experiments Fool
Yourself The Better to Fool Others
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Evolution of Self Deceit Subconscious
mind Polygraph playback experiments Fool
Yourself The Better to Fool Others
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Evolution of Self Deceit Subconscious
mind Polygraph playback experiments Fool
Yourself The Better to Fool Others
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Summary of Direct Pairwise Interactions Between
Two Populations __________________________________
________________________________________
Species Type
of Interaction A B
Nature of Interaction
_________________________________________________
_________________________ Competition
Each population inhibits the other
Predation, parasitism, Population
A, the predator, parasite, and Batesian mimicry
or mimic,
kills or exploits members

of population B, the prey, host, or model

Mutualism, Interaction
is favorable to both (can Müllerian mimicry
be obligatory or
facultative) Commensalism 0
Population A, the commensal, benefits
whereas B, the host, is not affected
Amensalism 0 Population A is
inhibited, but B is unaffected
Neutralism 0 0 Neither party affects
the other ________________________________________
__________________________
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Indirect Interactions Darwin Lots of
Humblebees around villages
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Indirect Interactions Darwin Lots of
Humblebees around villages
bees gt clover
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Indirect Interactions Darwin Lots of
Humblebees around villages
bees gt clover
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Indirect Interactions Darwin Lots of
Humblebees around villages
mice o bees gt clover
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Indirect Interactions Darwin Lots of
Humblebees around villages cats o
mice o bees gt clover
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Indirect Interactions Darwin Lots of
Humblebees around villages spinsters
gt cats o mice o bees gt clover
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Indirect Interactions Darwin Lots of
Humblebees around villages spinsters
gt cats o mice o bees gt clover gt beef
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Indirect Interactions Darwin Lots of
Humblebees around villages spinsters
gt cats o mice o bees gt clover gt beef gt
sailors
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Indirect Interactions Darwin Lots of
Humblebees around villages spinsters
gt cats o mice o bees gt clover gt beef gt
sailors gt naval prowess
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Indirect Interactions Darwin Lots of
Humblebees around villages spinsters gt
cats o mice o bees gt clover gt beef gt
sailors gt naval prowess Path
length of seven! Longer paths take longer
(delay) Longer paths are also weaker, but there
are more of them
gt
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Indirect Interactions
Trophic Cascades Top-down, Bottom-up
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Competitive Mutualism
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Complex Population Interactions
Rob Colwell
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Mutualistic Interactions and Symbiotic
Relationships Mutualism (obligate and
facultative) Termite endosymbionts Commensalisms
(Cattle Egrets) Examples Bullhorn Acacia
ant colonies (Beltian bodies) Caterpillars
sing to ants (protection) Ants tend aphids for
their honeydew, termites cultivate
fungi Bacteria and fungi in roots provide
nutrients (carbon reward) Bioluminescence
(bacteria) Endozoic algae (Hydra), kidnapped
chloroplasts Endosymbiosis (Margulis)
mitochondria chloroplasts Birds on water
buffalo backs, picking crocodile teeth Figs and
fig wasps (pollinate, lay eggs, larvae develop)
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Nudibranchs
Green sea slug
Hydra