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Population - Coggle Diagram
Population
Human Populations 4.1
Human Population Growth
Pronatalist Pressures
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Childhood Mortality Rate - The number of children under 5 years of age that die per every 1,000 live births in that year.
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Desired Fertility - The ideal number of children an individual indicates he or she would like to have.
Demographic Transition
Industrializing - Better conditions lead to lower death rates; however, birth rates remain high, resulting in rapid population growth.
Mature Industrial - Birth rates begin to fall, though they still outnumber deaths; population is still growing but at a slower rate.
Preindustrial - Birth and death rates are high but similar, so population growth is slow or stationary; population size is low.
Postindustrial - Birth rates are similar to death rates, so population growth stabilizes at a new higher population size.
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Population Dynamics 2.2
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minimum viable population: the smallest number of individuals a population can support without harm to the genetic diversity and functioning behaviors (mating, grouping, nesting)
density dependent factors: effects that a population experiences because of its size (predation, disease, competition)
density independent factors: effects a population not based on size (like natural disasters, abiotic)
population growth rate: birth rate minus the death rate, factor in emigration and immigration
death and birth rates
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resistance factors: causes resistance on a population, keeping growth in check, can cause negative growth, are a direct influence
biotic potential: when the population increases perfectly (no resistance to growth, every offspring survives)
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K species: slow growing, long lifespan, low fecundity, rely on consistent environment (don't adapt quickly)
can easily maintain population in a mature environment but takes a while to bounce back after huge drop (most endangered species are K species because of this)
R species: fast growing, high fecundity, short lifespan, able to adapt to fast changing environment
rapid fluctuation, peaking and crashing below carrying capacity, eventually levels out but it prone still to changes
bottom up regulation: regulated by presence of absence of growth factors (availability of water and food) determines how much energy enters the ecological community from the bottom
top down regulation: presence of absence of predators, determines how much energy is evenly distributed throughout the food chain