HUMAN ADAPTABILITY Definitions Types of Adaptation Adaptation to Climate
Jan 01, 2016
HUMANADAPTABILITY
HUMANADAPTABILITY
DefinitionsTypes of Adaptation
Adaptation to Climate
Stress -- a condition that disturbs the normal functioning of the organism
Fitness -- reproductive success; the ability to produce viable offspring who themselves reproduce, with minimal energy expenditure.
Basal Metabolic Rate -- the amount of energy the body needs to maintain its function in an absolute resting condition
Functional Adaptation -- involves changes in the body either as independent systems or in the organism as a whole
• Acclimatization - long term• Acclimation - short term• Habituation - gradual reduction
Cultural Adaptation -- non-biological changes passed on as a part of socialization
Genetic Adaptation --
the process whereby a population becomes genetically fine-tuned to the environment.
Controversy as to whether this form of adaptation exists in Homo sapiens.
• skin color• birth weight• O2 absorption• lung capacity
ArcticMountain
Tundra
Deciduous
Rainforest
Grassland
SavannaDesertChaparral
Mountainsof the World
Main Difficulties -- • getting enough O2• cold; increased radiation• low biodiversity
Biological Adaptations -- • increased pulmonary capacity• increased RBC production
Cultural Adaptations -- • use of adapted animals• high carbohydrate diet• use of cocoa
Additional responses -- • slowed maturation• reduced sexual dimorphism• resting HR goes from 70 beats/min to
105 beats/min• light sensitivity decreases• memory & recall diminish• food preferences for sugars• anorexia and weight loss
Arctic Regionsof the World
Main Difficulties -- • cold• low biodiversity• long periods of darkness
Biological Adaptations -- • shivering responses; increase BMR• non-shivering thermogenesis• long noses; body form• brown adipose tissue
Cultural Adaptations -- • clothes, fire, & housing• high protein diet
Bergman’s Rule -- • in bodies of the same shape, the
larger has less surface area
• increased amount of metabolic tissue therefore internal heat gain is greater
Increase BMR -
• basic level of heat production by the body based on chemical reactions of metabolism
• muscular activity can raise BMR by 5 times
• several hormones raise BMR such as epinephrine, norepinephrine, and thyroxine
• dietary intake causes an increase in metabolic rate as body works to digest food
Core Shell Model - • vasoconstriction causes blood to
pool and conserve organ heat
• vasodilation increases the flow
Desertsof the World
Main Difficulties -- • hot & dry• lack of water• lack of biodiversity
Biological Adaptations -- • lower pulse rate• decreased salt output in sweat• body form• highly tanable skin
Cultural Adaptations -- • houses of adobe, cloth• clothing aids evaporation• activity patterns
Allen’s Rule -- keeping mass constant, increasing surface area with long, linear form
Skin Color -- • brunette tanable
• UV radiation, vitamin D production
• melanin; conduction
Rainforestsof the World
Main Difficulties -- • heat loss is difficult• low animal biodiversity
Biological Adaptations -- • highly tanable skin• ready onset of sweating• short broad nose
Cultural Adaptations -- • live near water• little clothing• low salt intake• reduced activity levels
“black body” radiation
Acclimatization to Rainforest -- • increased peripheral heat
conductance
• high vasodilation & blood flow• lower sweat output• enhanced sodium resorption