Transcript Human Ethogy Inttro 2010

What is Ethology?
“comparative animal behavior”
Primary method of study is the
observation and quantification of behavior
in the field and lab.
“Human Ethology” ?
So, how does the “human” part change the
field?
Acknowledges unique biological
attributes of the human species, how
BOTH human culture and biology
evolved to become inter-dependent
In A Word...What is
the human part of
ethology?
Culture:
dependence on tools, symbols,
language and learning for survival…
genetic and behavioral plasticity
and capacity for immediate innovation
(change)--environmental regulation
Like……here are some examples..






beliefs about how babies should be born..changes the biological
experience of birth..(labor duration)
socialization either favoring or discouraging aggression makes it
harder or easier to be aggressive…
expectations and beliefs about food, the psychology of food,
changes what we eat and why..affecting our health..
 Mead said:” We don’t eat food, we eat ideas about food”;
how and where we sleep, and what we think about a “good nights
sleep” depends on our cultural beliefs…
What is it that actually happens when we “psyche
ourselves up” or “hit that groove..”
Humans make decisions
Evolutionary Perspectives on…
Human beings…
Early bipedal
hominines
3.5 million years ago,
390 cubic centimeters of
brain to…
Homo sapiens sapiens
50-150,000 years
ago..1500cc’s
What does it mean to
evoke evolutionary
concepts into our
understanding of
humanity…
For the sake of the babies
800,000
150,000
400,000
Changing morphologies and
Changing behavior over time
130,00
32,000
3mya
2mya
1mya
.5mya
Today
The Hominins
↓ Humans → → → →
↓
↓
Homo sapiens
sapiens
Filling in the dots…..
A day in the life of a Pleistocene, early
Homo baby, 800,000 years ago.
For the sake of the
babies?…How?
Any
Relevance
to the
western
2009
baby? Us?
Absolutement !
We are a species that invented the phenomenon of
“ideas” sometimes referred to as “memes” the
culturally-based, functional analog to biologicallyconstituted “genes”.
Nonetheless, ideas operate and are expressed in
relationship to an ever-present, powerful, successful,
paleolithic (Stone age) biology.
Still, ideas (or memes) change faster than infant or
maternal biology ..
as ideas or memes..are made possible by…
The evolution of the human brain…increasing
encephalization relative to body mass..
MODERN
HUMAN
MODERN
CHIMPANZEE

increasing complex problem solving abilities involving regionalized tools
and technologies, enhanced communication and interpretive socialskills, extended, bi-parental care in the context of more enduring malefemale sexual relationships, symbolic behavior and belief systems
Stanley Kubrick “2001”: The perfect visual metaphor..for
illustrating what anthropology tries to do
From this
To
that

We try to fill in the dots between fossil ancestors, connecting
hominine fossils with each other through time..and
reconstructung the relationship between morphology (brain size,
anatomical characteristics ….and social behavior…
Homo sapiens sapiens-US
The Indonesian
“hobbit”….3.6 ft feet tall,
800 cc brain..late Homo
erectus, up through
300,000 to 15-11,0000
BP years
ago…overlapping
modern forms…phyletic
dwarphism isolated on
ecologically attractive
but competitive
environment
“Homo sapiens
florisiensis” hunting
large rats and
Kokomo dragon
Brain Quality and Volume And the Rise of Human
Culture
-------------]
Modern
Human
size
Range
]
________]
So, my friends….where were we…? in our warming up to think
differently about contemporary human behavior..adding an
additional framework..time depth..background, tools to
understand….






defined “ethology.”.now working on defining what it
means to do “human” ethology…
leads to understanding relationship between biology and
culture…(brain size and behavior) the background and
features associated with human evolution..
what happened, why, what is different about us.
.how did we do it? How do we know?
What is the “human” evolutionary legacy?
Tools of Human Ethological Research
David Barash: The Tortoise and The
Hare (1987)
“ …There would be little if any
difficulty exchanging a CroMagnon and a modern infant,
but great incongruity in making
the same switch amongst adults
of both cultures.”
And what else does culture do?
Answer: (Lots)
“Although the biology of human
behavior is universal in historic time
how humans perceive what the
SHOULD do..or what is..ahhh
“cool”….is socially constructed and
subject to historical change.”
(adopted from Sussman 1982)
Human Culture and Brain Size
Wood? stone
choppers,
unifacial flaked
toolsl
Fire, shelters,
systematic
hunting,
clothing, hand
axes, flake
tools,
migrations
-------------]
Modern
Human
size
Range
]
________]
Language,
burials,religion?
integrated tools,
agriculture, pottery,
sedantism
Human Population Growth Last
10,000 Years
How Did We Manage To Afford Such An
Expensive Brain, Slow Developing Brain,
Needy Brain, With A Relatively Larger
Body Size and Reduce Birth Intervals at
the same time?
HUMMMM…HOW DID WE DO
THIS
HOW?





Increased size of foraging home ranges;
Shifted to enormous breadth of food types with high protein
omnivory coupled with production of tools to harvest and prepare;
We cook, too!
Food sharing in social context, division of labor , with non-relatives







no less!
Reduced mass of gut;
Emancipation of sexual behavior from hormonal control..
Symbolic communication; non-verbal communication (mix)
Birth to fat, really “cute” babies!
Rise of alloparents..to become cooperative breeders!
Make/Depend on Tools..(fake organs?)
Risks? Of a big brain…
Still, the Risks:
second trophoblastic
invasion..(eclampsia, pre eclampsia
result) as emerging embryo penetrates
more deeply into womb for increased
oxygen and nutrients
Architecture of bipedal pelvis diminished
outlet complicating labor and delivery;
Cultural construction of birth and infant
caregiving practices…far from ideal?
Risks of preeclampsia….defective implantation
of the placenta…a couples disease…
Disease of first pregnancy….10% of all human
pregnancies…3 months after first implantation..in uterus (the
zygote)..inefficient penetration of the placenta..leading to
increased blood pressure..to get nutrients to fetus…
The longer the father has exchanged fluids with
the mother, therein exposing her to his antigens,
the less likely the disease finds expression!
Hypertensive disorders of pregnancy..
preclampsia (edema) and eclampsia
(convulsions)
Caused by…..short periods of
male-female cohabitation….40%
of couples with less than 4 months
of cohabitation; 25% amongst
those with 5 to 8 months; 15% of
those with 9-12 months; and 5% of
those with more than 12 months
Why Humans?
Human fetal brain requires 60% total maternal
nutritional supplies in utero compared with 20%
demand of maternal energy in utero amongst the
other 4300 mammal species!!
On human unique nesses:






Symbolic (verbal and non-verbal) capacity-language, self awareness,
reflection, evaluation; awareness of death;
Retention of breasts;
Variable adult male parental investment;
Technology (dependence on tools)..culture
Mind readers..empathic, tolerant, understanding;
Reduced gut mass, efficient digestion;
On human unique nesses:

Bipedal, long labor, woman attended birth; birth
of fattest babies
Extreme Delayed maturity;
Largest neo-cortex and relative to body
size..tissue convolutions maximize axonaldendritic connections and speed;
Long child dependence, food sharing;
Increased parental investment;
Concealed ovulation, loss of estrous;
Post reproductive senescence (life after
menopause)
Direct and indirect male care

Energetically costly babies, BUT short intervals between births;







“Will the Real Pleistocene Family Please Stand
Up?” (after Hrdy 2008)
Environment of
Evolutionary
Adaptedness??
For the sake of the
babies…
what was a day like in
the life of an 800,000
year old Homo?
Shortened birth
intervals
explained by:
Cooperative
breeding (Hrdy
2008) ?
Direct male
care (Gettler in
press) ?
The primacy of cooperation amongst early
human beings ….living on the savannah..





Humans are geniuses at
mutual understandings ..
Caring about and imagining
what others think, and what
something means to the
other..
Caring about the intentions
(intentionality ) –
Figuring out what others
might do and what the self
should do in relationship to
others;
Developing a “theory of mind
“
Bipedal life on the
savannah and in the forest
required social planning
Relevance of Past Selective Pressures to
Contemporary Behavior? Meet the “EEA”
Meet the neighbors!
Really, A Central Question For the
Class is:
What Is Human Nature?
(Or is it, really natures?)
What Aspects of Human Life
Constitute a “Nature” ?








Emotional and Behavioral “tendencies” ?
How we sleep? Why we get fat? Fight? Select Food? Laugh?
Give birth? Satisfy Hunger? Own things? Want things?
Raise our babies (parent)? Protect our babies? Soothe (or not)
our babies?
Stay healthy, trade health for other gains?
Look for, look good, and find a mate? Circumstances of having
sex and being sexual?
Communication skills (interact successfully…conduct social
business, appease, maintain group cohesiveness, reduce
ambiguity, build unity?
Desire to discover? Learn? Explore? Feel? Empathize/ Control?
Be “Happy” (a new concept)?
What determines the “nature’ of
human nature?



genetic, familial, historical, cultural, physical,
economic and environmental processes;
“Natures” may be extremely variable, flexible and
diverse: sensitive to the social values, ideologies
and overall cultural practices of the groups within
which the behavior develops;
Culture plays a huge role….even that we think it
important to know what our “natures” are…
Why does your answer to the
question--what is human nature -matter?
because
“..the behavior of men is not
independent of the theories of
human behavior that men adopt”
Leon Eisenberg “The Nature of Human Nature” pg 165
(1972)
How we define people..what you expect of
them..i.e. define their natures..becomes a selffulfilling prophecy

Evolution of the concept of mental retardation…



Middle ages..defined as insane..sent to prisons..treated
like animals and so like raving maniacs they became..
17th Century….mentally retarded treated like
children..juveniles, stripped of adult rights..and so like
children they became..barely learn sentences…
21st century USA..”mainstreaming”..full educational
experiences..life experiences…opportunities..and so like
independent functioning citizens the …mentally slow
become
Why Important?
“Pessimism about man serves to
maintain the status quo”.
Leon Eisenberg pg. 167 1997 “The Nature of Human Nature”
A question...
Are human emotions the closest we
will ever get to understanding our
genes, i.e. what you feel, rather
than what you act on, or necessarily
do?
Human Ethology: Uses Diverse “Lines
of Evidence”

Comparative (what kind)



Cross-cultural (other societies)
Cross species (other species)
Inter-individual (intra-sexual) differences;

Developmental (the life cycle--from blast cyst-

embryo-fetus-neonate-infant-child-adolescentadult)
Evolutionary/Phylogenetic origins/function
Human Etholgists Ask Five Fundamental
Questions:


What does the behavior look like? Ahh! observation!
What causes the behavior to occur?


How does the behavior develop?


Ontogeny: individual life cycle
How, why and when did the behavior evolve?


proximate cause vs. ultimate causes
Behavioral Phylogeny--how is it adaptive?
How does the behavior function?
Assumptions Underlying Human Ethology




successful behaviors evolve;
behavior mediates between the organism’s genes
and environment for maintenance --all leading to
reproduction;
But what is being “selected” or “favored”
genetically is often difficult to say…
is the “trait” “epiphenomenon” (that is, noise) or a
real, biological, evolved “adaptation”?
We assume that:
a relationship exists between the degree
to which the environment (social or
physical) can change genetic expression-and behavior..and the degree of
complexity of the animals’s nervous
system …(brain size)
the larger the neo-cortex--the more the animal depends
on learning..greater plasticity in behavior
Human Brain Expansion Over
Time

Species with
larger brains
can alter their
behavior
quickly to
changing
environmental
demands
Assumptions con’t


Organisms use energy resources differently
at different stages of the life cycle..behavior
changes with age: growth, maintenance
and reproduction (life history theory).
Cultural behavior (learning) changes the
degree, form, and expression of genetically
based human behaviors…long chain
between genes and behavior…
Another Assumption
Culture changes much faster
than does human biology.
(no dependence on
genes)…only dependent on
human creativity..insight,
ideas…
Memes Vs Genes ?
Dawkins (The Selfish Gene)
“memes” refer to non-organic
behaviors, innovations, or ideas passed on
quickly from one person to another, one
generation to another which while not
based on biology nonetheless have both
biological and cultural significance.
Fundamental Concept In Ethology
Evolution: change in the
genetic structures and general
behaviors of organisms through
time…achieving adaptation
(reproductive success)
Concepts/Questions
basic to ethology
(human or otherwise):
“analogous” traits vs. “homologus”traits
Examples; human smile? hand
grasp/shake? Reproductive strategies?
Facial expressions, living in groups?
Sleep? Birthing?
What does a “belief” in evolution really
mean.. (it’s the wrong word, actually)



evolution by way of natural selection makes
no presumptions about the presence of
absence of God!!
Religion and Science are not in
competition..they depend on different
things: science (on evidence) religion (on
faith)..They co-exist like apples and oranges
Nobody should “believe” in evolution...no more than you
believe in gravity… water….eggs…..air
Useful Intellectual
Concepts….
proximate vs. ultimate causation
immediate cause/function
how a behavior confers fitness
Social Darwinists ? A Mistaken Application
of Darwinian Principles…
Darwin never argued that “aristocratic
white English ..men” evolved because
they represented the..”survival of the
fittest”..nor that “classes” of people nor that
certain “superior” cultures evolved…
(Only that successful independent traits
evolved…though he knew not what actually
passed from one generation to another)
Evolutionary Processes:
Kin selection (nepotism rules!)
 Sexual selection (why we are so pretty)
 Natural selection (how to get adapted)
 Individual reproductive fitness (how many
offspring, relative to others)



reproductive strategies (whatever works)
Inclusive fitness (your offspring, plus that of
your relatives)
Ethological concepts



Fixed-action pattern FAP (actors vs.
receivers)..species behavioral repertoire
Ritualized (species-specific) behavior
Signals (conspecific-- same species)



Motivation (underlying “feeling”--hormonal)
Meaning (reaction of other animal)
Function (what did it accomplish for actor)
Rituals, ceremonies, rites of
passage..biology and culture together ?

Cultural rituals as social communication:



Birth, death, transformations from one status to
another, liminality, fasting, sacrifice, birthdays,
holidays;
Puberty, childhod to adulthood, engagement,
marriage, ascendancy, graduation…
Religious ceremonies, special clothing,
paraphanalia-used, magic and special
instruments know only to practitioners;
routinization..stereotypical behavior..
On our babies….what’s so special
about…them/us?
At birth the human infant is the
least neurologically mature
primate of all, and the most
reliant on physiological
regulation by the caregiver, for
the longest period of time.
Percentage of Adult Brain
Size
Chimpanzee Infant Human Infant
At Birth
3 months
6
9
1 year
2
4
8-9
45
50
60
65
70
75
85
100
25
35
45
50
60
70
80
95
*(100% at 14-17 years)
Biology of Mother’s Milk Reflects
Evolved Infant Needs
Cache Species
(Ungulates)



high fat
high protein
low carbohydrate
(high calorie = long
feeding interval)
vs..
Carrying Species
(Humans)



low fat
low protein
high carbohydrate
(low calorie = short
feeding interval)
Human Evolution Is Not Linear
Note overlapping species through time…
Hominid
Phylogeny
(family tree)
Note periods
of adaptive
radiation
What Made Us Human? A biological systems approach.
Hidden Regulatory Mechanisms



a given interaction may be guided and even determined by
processes hidden to observation; nutritional status of
infant, heat, smell, touch, vestibular;
repeatedly delivered sensory regulation may have
cumulative effects which influence adult roles and behavior
by way of:
internal state responses by baby to caregiving behavior
(blood pressure, satiation, anxiety, breathing, heart rate)
may be altered by specific aspects of their relationships
(labile traits) like being touched, spoken to, and fed
frequently (neuro-developmental, long -term effects)..
Hidden Regulatory Mechanisms


systems involved in regulating internal
states of another especially altricial infant
mammals like the human infant include:
nutritional, vestibular, tactile, olfactory,
auditory, visual;
what is the evidence that they exist for
human infants?
The evidence for “hidden”
regulation?



low affect of infants born to depressed mothers
and (learned helplessness);
failure to thrive, weight gain reduced, increased
morbidity, anaclitic depression;
benefits of skin-to-skin contact (Anderson 1991)
 robust weight gain, more robust breast feeding, reduced
apneas, less crying, warmer skin temperature; shorter
hospitalization;
8
7
6
5
4
3
2
1
0
6
RB-SN
RS-SN
5
# of infants
# of infants
Distribution of Number of Breast Feeds Solitary vs.
Bedsharing Infants
4
3
2
1
0
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
10 11 12
# Breast Feeding Episodes
10 11 12
8
7
6
5
4
3
2
1
0
RB-BN
# of infants
# of infants
# of Breast Feeding Episodes
1
2
3
4
5
6
7
8
9 10 11 12
# Breast Feeding Episodes
8
7
6
5
4
3
2
1
0
RS-BN
1
2
3
4
5
6
7
8
9
10 11 12
# Breast Feeding Episodes
Mother and Infant Body Orientations on Bedsharing
Night (BN) vs. Solitary Night (SN)..for routine
bedsharers (RB) and routine solitary sleepers (RS)
(in min)
400
350
300
250
200
150
100
50
0
M
F
I
M
F
A
I
F
M
RB-BN
RS-BN
I
F
A
*F
(Face Each Other)
E
O
From: Richard et al.,
Sleep 19 (9) 1996
Sampling Maternal CO2
Contribution: Study 2



1) using the infra red video
tapes we converted
distances (nares-to-nares)
maintained by 12 routinely
bedsharing mother-infant
pairs (sleeping together on
their bed sharing night) to
real distances;
2) a mass spectrometer
was used to measure C02;
3)mother’s contribution to
the C02 environment did
not reach 5%
Laboratory vs. Home Breastfeeding Behavior
(Observed vs. Sleep Log)
RB vs. RS, p<.008, t-test
5
4.5
4
3.5
3
2.5
2
1.5
1
0.5
0
4.7
2.4
RB
RS
2.3
1.6
Home
Laboratory
(recall)
(observed)
Studies which compared
observed breast feeding
with mother’s recall show
that mothers recall about
50% of her actual breast
feeding sessions;
(Mothers consistently
overestimate
duration of feeds, but
under-estimate frequency,
Vitzhum 1994)
Choice of child care “practice” has physiological
consequences for infant development
Choice of Routine Sleeping Arrangement
Cosleeping (?)-------------------------- Solitary Sleeping (?)
choice affects:
breastfeeding duration, frequency, infant sleep position,
arousal patterns, sleep architecture,
maternal inspections, thermal and CO2 environment,
infant crying, heart rate and breathing, emotional
(interactional) expectations from parent, sensitivity to
presence of ”other”
Mean Interval Between Feeds (in min)
Per Group Per Night
200
RS
(routine experience)
180
179.94
160
140
140.51
117.21
RB
RS
120
100
80
BN
97.81
RB
(routine experience)
SN
Infant Sleep Development
?
Evolutionary
infant needs/characteristics
in relationship
to parental emotions,
responses
Experimental
Ecology..how is sleep
studied?
(solitary, bottle fed)
Family Ecology
size, SES,
ethnicity,
beliefs,
psychological
constellation
Cultural Ecology
physical setting
values, ideology
medical views
socioeconomics
Normal Infant Sleep?







Dis-articulated from
mother’s body...
Breast feeding?
Touch?
Olfactory cues/
Movement cues?
Rhythms /”zeitgeber”
Maternal-Induced arousals
& regulation?