ANT: Module 4 Discussion
Module 4
Human Adaptation
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Midterm Exam
50 Multiple choice, true/false, and/or matching questions
Covers lectures, videos, and textbook chapters assigned since first day of class
50 minutes to complete
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Human Adaptation
Human face same adaptive challenges as all other organisms
In addition to biological adaptations, humans also have culture to increase adaptation
Culture has a biological basis: rewards sociability and inventiveness
Because of culture, people have adapted to almost all of the earth’s terrestrial habitats
Eastern Siberia (-80 F°)
Eastern Siberia -62 C (-80 F)
Dallol Africa, Ethopodia = 120 F average yearly 94
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Dallol, Ethiopia (120 F°)
Adaptations and Adaptability
Humans have biological plasticity, or ability to adapt to environment
An adaptation is any variation that can increase successful interaction of a population with its environment
Adaptations may be biological or cultural in nature
Biological Adaptation
Acclimatization
Developmental Acclimatization
Genetic
Vary in their length of time (from minutes to generations)
Depends on the severity and duration of stressors
Acclimatization
These adaptations can take seconds to weeks to occur and are reversible within an individual’s lifetime
Perspiration
Tanning
Cultural adaptations: sunscreen and coats
Developmental Acclimatization
Occurs during an individual’s growth and development
Cannot take place once the individual is fully grown “magic time window”
High altitude
Intentional body deformation
Maya elite reshaped the skull
Foot binding in China
Neck stretching in Thailand
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Genetic Adaptations
Genetic adaptations can occur when a stressor is constant and lasts for many generations
Genetic adaptations are environmentally specific: a particular gene may be advantageous to have in one environment, and detrimental in another
Sickle cell: Malaria adaptations
Skin color: UV radiation
Body size and shape: extreme temperatures
Fight or Flight Response
In bedroom battle, man kills buck with his bare hands
(BENTONVILLE, Ark.) -- It looked like a crime scene, but no charges will be filed after Wayne Goldsberry killed a five-point buck with his bare hands in his daughter's bedroom.
After an exhausting 40 minutes struggle , Goldsberry finally was able to grip the animal and twist its neck, killing it
Goldsberry, sore from the struggle, dragged the dead animal out of the house.
Benton County Sheriff Keith Ferguson said that when he arrived he found the deer dead in the front yard. Goldsberry intended to have the deer processed for its meat.
-November 2005-
Badass of
the Year
The Fight or Flight Syndrome: An Adaptation to Threat of Harm
Escaping a predator means mobilizing the bodies’ defenses: increasing alertness and energy
Once the threat is over, body returns to normal
Same mobilization of defenses in response to threat as our Paleolithic ancestors
HOWEVER: we developed a new way of adapting -
-- Culture --
These include the following:[4]
Acceleration of heart and lung action
Paling or flushing, or alternating between both
Inhibition of stomach and upper-intestinal action to the point where digestion slows down or stops
General effect on the sphincters of the body
Constriction of blood vessels in many parts of the body
Liberation of nutrients (particularly fat and glucose) for muscular action
Dilation of blood vessels for muscles
Inhibition of the lacrimal gland (responsible for tear production) and salivation
Dilation of pupil (mydriasis)
Relaxation of bladder
Inhibition of erection
Auditory exclusion (loss of hearing)
Tunnel vision (loss of peripheral vision)
Disinhibition of spinal reflexes
Shaking
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Cultural Adaptations
Cultural adaptations can occur at any time and may be as simple as putting on a coat when it is cold or as complicated as engineering, building, and installing a heating system in a building
Culture as an Adaptation
Culture helps us adapt to our environment
Symbolic communication
Social organization
Increasing Cultural Complexity
Societies have become increasingly complex
But genetically, we still have Paleolithic bodies
Coping with the modern world– in our Paleolithic bodies--has many effects
Culture and Individual Adaptation
Culture as the environment
As culture becomes more complex, we have to adapt to it
Biological responses that can be adaptive when faced by a physical threat may be maladaptive—or stressful—in the face of symbolic threat
Environment
Individuals
Culture
Mashco-Piro Indians
Sources of Stress in the Modern World
Stress is not purely psychological
Instead, revolves around culturally-defined social expectations
Loss of status through failure to achieve social expectations can elicit the same biological response as a threat to our physical well-being
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Protective effects of the social environment
‘Modernization’ or ‘globalization’ has led to rapidly changing expectations
At the same time, as in Paleolithic times, sources of help and support in the social environment can moderate the impact of stress
Studying Sociocultural Change and Stress
Two major approaches
Studying migrants to more complex societies
Studying people caught in a process of change
How to measure the impact of adaptation
Blood pressure
Relatively easy to measure
Associated with most of the major modern diseases
Influenced by various biological pathways that are thought to be important in sociocultural change
Samoa
Hawaii
BP and Migration in Polynesia
Blood pressure
Why?
The obvious reasons
Obesity (although Samoans are big to begin with)
From yams and fish to Big Mac and fries
The not-so-obvious reasons
In Western Samoa, the most traditional area, life is dominated by subsistence and the extended family
In California, there is the struggle to create a life as defined by the American middle class, and there may not be a family support system to help