Transcript Last chapter - newyorksparrow

How is language
originated?
1.Gestural theory:
Human language developed from gestures
that were used for communication.
Gestural language and vocal language depend
on similar neural systems.
Nonhuman primates can use gestures or
symbols for primitive communication.
1. Gestural learning
and speech learning
: around the same
cortex region
-- Gestural language
in chimps
2. Infant babbling
Moving their limbs
while making
the babbling sounds.
1. Gestural theory: Human language developed
from gestures that were used for
communication.
Gestural language and vocal language depend
on similar neural systems.
Nonhuman primates can use gestures or
symbols for primitive communication.
Gestural language in chimpanzees
1. Associate words  objects
2. Associate words  signs
2. Culture-domestication theory:
domestication relaxed selection pressure for
stereotypic songs in the songbirds…
our cultural domestication have relaxed
selection on many of our primate behavioral
traits, allowing old pathways to degenerate and
reconfigure.
Black-capped chickadee:
In Nature
In the lab
Domesticated foxes have high
behavioral variability
Many traits have changed in the
domesticated farm foxes
1.Floppy ears, curled tails
2.Patches of white fur
3.Lost musky fox smell
4.Barking, wagging tails, licking humans
5.Reduce fear response (corticosteroid)
How is language
originated?
Evolution of vocal tract?
Evolve from gesture language?
Evolve from cultural domestication
Last chapter!
Evolution of
human behavior
Is there a role for
evolutionary theory in
helping us to understand
ourselves?
Natural selection: Animal Behavior
Human behavior is shaped by
natural selection?
Natural selection:
Our behavioral attributes
should help us pass on our
genes to the next generation.
How about Culture?
Cultural tradition
influences our behavior
Cultural influence
on human behavior
Evolution theory provides
us a testable hypothesis
for us to better understand
ourselves
Blood-donation
Evolutionary adaptive?
Cultural dependence?
Animals: altruistic behavior
Food sharing in blood-sucking vampire bats
Tit for tat strategy
Female bats regurgitate blood meals to others that failed to obtain food
Altruism in Pied kingfisher
Young
r
f1
O
r
s
m
f2
Primary helper
1.8
x 0.32 = 0.58
2.5 x 0.50 x 0.54 x 0.60 = 0.41
Secondary helper
1.3
x 0.00 = 0.00
2.5 x 0.50 x 0.74 x 0.91 = 0.84
Delayer
0.0
x 0.00 = 0.00
2.5 x 0.50 x 0.70 x 0.33 = 0.29
O= offspring; s = p of survival to next year; m= p of finding a mate in the second year
Hamilton’s rule: altruism can evolve if:
*C x rc < *b x rb
If the relatedness of the altruist to
the relatives it helps (rb) is particularly
high, then indirect fitness would
be increased.
Animals: altruistic behavior
1. Indirect benefit from inclusive fitness
2. Direct benefit: Chance to acquire
resource/ reproductive success
Blood-donation
Evolutionary adaptive?
Cultural dependence?
Evolutionary hypothesis
of blood donation:
Blood donor is repaid by
the donor’s everyday’s
companions
.
How do you test this
hypothesis?
Prediction: donors should
let their friends know…
√
How do you test this
hypothesis?
Prediction: people will be
reluctant to broadcast
their refusal to donate…
√
How do you test this
hypothesis?
Prediction: when people
have a choice of other
people to help, they
prefer to help……
√
Evolution of human
cultures
Rich diversity of human
traditions:
How can human culture be
due to natural selection?
Complex social decision
White-fronted bee-eaters
Female helper
White-fronted
bee-eaters
Complex social decision
Females base their reproductive
decisions on their behavioral flexibility
and sophisticated evaluations of their
social environment.
Complex social decision
Humans base their reproductive
decisions on their behavioral flexibility
and sophisticated evaluations of their
social/ cultural environment.
Arbitrary culture theory
Our culture reflects arbitrary process by
which traditions originate and persist
over time.
--Nothing to do with fitness
Your oral presentation
1. Eye contact
2. Few words per slide
3. Focus: one topic
4. Timing
5. Organize
6. Memorize
7. Practice
Human cultures
Nature selection?
Rich diversity of human
traditions:
Is human culture partially
selected by natural selection?
Final exam question:
Can Blood-donation
be explained by
evolutionary theory?
Final exam question:
Adoption
Is adoption simply a culture phenomenon,
or it has its evolutionary roots?
Evolutionary hypotheses for
adoption is supported by
1. Inclusive fitness:
2. Direct benefit:
Most adopters cared for
children who were cousin
or closer (r=0.125)
Alternatively, adoption is
supported by
mal-adaptive hypothesis
Adaptive proximate mechanisms
for love and care of children:
 mal-adaptive
Mal-adaptive hypothesis
Predictions:
Couples lost the only child,
or fail to produce children,
prone to adopt stranger
Mal-adaptive hypothesis
animal examples?
Mal-adaptive hypothesis
animal examples?
Evolutionary theory for
adoption is supported by
1. Inclusive fitness:
2. Direct benefit:
3. Mal-adaptive proximate mechanism
Final exam question:
Mate choice
Mate choice in humans:
has its evolutionary roots?
Evolutionary models of
mate choice in animals
•
•
•
•
1. Good gene hypothesis
2. Direct benefit hypothesis
3. Runaway hypothesis
4. Sensory exploitation hypothesis
Good gene hypothesis
Peacock’s tail is a honest
signal of the male’s
genetic quality
Choose this male will
Increase a female’s
reproductive success
Good gene provides indirect benefit
Good gene hypothesis and MHC gene
Evolutionary models of
mate choice in animals
•
•
•
•
1. Good gene hypothesis
2. Direct benefit hypothesis
3. Runaway hypothesis
4. Sensory exploitation hypothesis
1. Direct benefit hypothesis
Female
scorpionflies
choose males
that bring large
prey items—food
Adaptive mate choice
A woman’s reproductive success
is advanced by access to a partner’s
material assistance and parental care
Women should find wealthy,
paternal men more attractive.
Adaptive mate choice
Market value vs. age
Testable NS theory:
Female choice maximizes
female reproductive success
Female preference changes during
menstrual cycle: good gene?
Male mating success is highly correlated with
male income
Human mate choice
In evolutionary theory,
Male’s reproductive success
is different from female’s.
Sex difference
in the desire
for sexual
variety
Casual sex and the partner’s intelligence
Sperm competition in humans?
Summer reading!
“Did you know you can beat
stress, lift your mood, fight
memory loss, sharpen your
intellect, and function better
than ever simply by elevating
your heart rate and breaking a
sweat? Aerobic exercise
physically remodels our brains
for peak performance…”
Homework assignment
Climate changes
1.Habitat changes
2.Species diversity changes
3.Some survive, some extinct
The mean winter air temperature of the Western Antarctic Peninsula, has risen 10.8
degrees Fahrenheit in the past half-century, delivering more snowfall that buries
the rocks the Adélie penguins return to each spring to nest — and favoring
penguins that can survive without ice and breed later, like gentoos, whose numbers
have surged by 14,000 percent.
In the past three decades, the Adélie penguins on the peninsula has fallen by
almost 90 percent. The peninsula’s only Emperor penguins colony is now extinct.
The climate warming has also upended the food chain, killing off the phytoplankton
that grow under ice floes and the krill, a staple of the penguin diet, that eat them,
by as much as 80 percent,.
Sexual conflict: Rape
Alternative
reproductive
strategy?
Rape is not just violent attack
Step-parental care
More conflicts between men and their stepchildren
Men provide less financial aid: stepchildren
Step-parenting and child abuse