HUMAN ADAPTABILITY HUMAN ADAPTABILITY Definitions Types 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 O 2 absorption lung capacity

Arctic Mountain Tundra Deciduous Rainforest Grassland Savanna Desert Chaparral

Mountains of the World

Main Difficulties -- getting enough O 2 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 Regions of 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

Deserts of 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

Rainforests of 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