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| 14700934924 | Population | Group of individuals of the same species living in a particular area. |  | 0 |
| 14700934925 | Fundamental characteristics of a population | Size, density, age/sex distribution, dispersion. |  | 1 |
| 14700934926 | Types of dispersion | Random (dandelions), clumping (elephant herd), uniform (penguins). | 2 | |
| 14700934927 | Population change | Four variables dictate changes in the size of a population. |  | 3 |
| 14700934928 | Additions to a population | Births and immigration. | 4 | |
| 14700934929 | Subtractions to a population | Deaths and emigration. | 5 | |
| 14700934930 | Mathematical model of population change | N1 = N + (Births + Immigrants) - (Death + Emigrants) | 6 | |
| 14700934931 | Environmental factors that influence population change | Food availability, space availability, predation/disease, # of mates, competition, environmental disasters. | 7 | |
| 14700934932 | Population growth | When no environmental constraints exist, a population is able to grow at its maximum capacity. | 8 | |
| 14700934933 | Biotic potential | Maximum capacity for growth in a population. Maximum reproductive rate of an organism. If given unlimited resources, how quickly could a population possibly grow. |  | 9 |
| 14700934934 | Intrinsic rate of increase | Rate of growth given unlimited resources. | 10 | |
| 14700934935 | How is rate of increase determined? | Birth rate - % of new births in a year (b). Death rate = % of deaths in a year (d). Intrinsic rate - r = b - d | 11 | |
| 14700934936 | Exponential growth | Unrestrained growth with a constant rate of increase (J curve). Growth at a constant rate of increase per unit time. Number of individuals added to a population at the beginning of exponential growth is relatively small. But numbers increase quickly as the population, and thus the given percentage of that population, grows. |  | 12 |
| 14700934937 | Exponential growth equation | dN/dt = rN r - intrinsic growth rate N - the initial population size dN/dt - amount of change in the population size per unit time. | | 13 |
| 14700934938 | Mathematic model to calculate the size of a population over a length of time | N1 = N0e^rt |  | 14 |
| 14700934939 | Doubling time | A useful concept in population studies that gives perspective in terms of how easy a population is actually growing. Useful measure to illustrate speed and magnitude of growth. | 15 | |
| 14700934940 | Doubling time equation | 70/(growth rate in percent) |  | 16 |
| 14700934941 | Malthus | An English economist and demographer; all biological populations have a potential for increase that exceeds the actual rate of increase, and the resources for the support of increase are limited. Recognized the potential for growth in all organisms and inspired Darwin to use this concept to explain change in populations over time. |  | 17 |
| 14700934942 | Environmental resistance | All the factors that act to limit population growth. Any environmental factor that reduces population growth. | | 18 |
| 14700934943 | Carrying capacity (K) | Number of individuals of a given species that can be sustained indefinitely in a particular area. There is a limit to the number of individuals that can be supported. The maximum population of a given species that a particular habitat can sustain indefinitely without degrading the habitat. |  | 19 |
| 14700934944 | Logistic growth | Exponential growth with a steady decrease in the rate of population growth over time as a the population encounters environmental resistance or approaches the carrying capacity (S curve). Growth rates regulated by internal and external factors until they come into equilibrium with environmental resources. Growth rate slows as population approaches carrying capacity. |  | 20 |
| 14700934945 | Logistic growth equation | dN/dt = rN (1 - N/K) |  | 21 |
| 14700934946 | When additions are greater than subtractions, the population _____________. | Increases. | 22 | |
| 14700934947 | When subtractions are greater than additions, the population _____________. | Decreases. | 23 | |
| 14700934948 | When addition equal subtractions, the population is _______. | Stable. | 24 | |
| 14700934949 | When resources are abundant, births tend to be ______ and deaths ____. Population tends to grow ________. | High, low, rapidly. Exponential growth. | 25 | |
| 14700934950 | When resources become scarce, births tend to go down and/or deaths tend to increase, population growth more ______, it _________, or ________. | Slowly, stabilizes, declines. Logistic growth. | 26 | |
| 14700934951 | Natality | Production of new individuals. | 27 | |
| 14700934952 | Fecundity | Physical ability to reproduce. | 28 | |
| 14700934953 | Fertility | Measure of actual number of offspring produced. | 29 | |
| 14700934954 | Immigration | Organisms introduced into a new ecosystem. | 30 | |
| 14700934955 | Mortality | Death rate. | 31 | |
| 14700934956 | Survivorship | Percentage of cohort (common age group) surviving to a certain age. |  | 32 |
| 14700934957 | Life expectancy | Probable number of years of survival for an individual of a given age. | 33 | |
| 14700934958 | Life span | Longest period of life reached by a given type of organism. | 34 | |
| 14700934959 | Emigration | Movement of individuals out of a population. | 35 | |
| 14700934960 | Arithmetic growth | Growth at a constant amount per unit time. |  | 36 |
| 14700934961 | Population oscillations | The population goes up and down. |  | 37 |
| 14700934962 | Overshoot | Measure of extent which population exceeds carrying capacity of its environment. | 38 | |
| 14700934963 | Dieback | Negative growth curve. Severity generally related to the extent of overshoot. |  | 39 |
| 14700934964 | Over time species may increase their capacity by developing ________. | Adaptations. Humans may develop technologies. | 40 | |
| 14700934965 | Some species maintain their capacity by ________________. | Migrating to other areas. | 41 | |
| 14700934966 | What has extended the earth's carrying capacity for humans? | Technological, social, and other cultural advantages. | 42 | |
| 14700934967 | Population density | The number of individuals in a population found in a particular area or volume. Affect how rapidly it can grow or decline (ex: biotic factors like disease, abiotic factors like weather). | 43 | |
| 14700934968 | Uniform distribution | Often reflects intense infraspecific competition | 44 | |
| 14700934969 | Intrinsic factors | Operate within or between individual organisms in the same species. | 45 | |
| 14700934970 | Extrinsic factors | Imposed from outside the population. | 46 | |
| 14700934971 | Biotic factors | Caused by living organisms. | 47 | |
| 14700934972 | Abiotic factors | Caused by non-living environmental components. | 48 | |
| 14700934973 | Density dependent factors | Higher proportion of population is affected as population density increases. Tend to reduce population size by decreasing natality and/or increasing mortality as population size increases. Interspecific interactions - predator prey oscillations. Infraspecific interactions - territoriality, stress-related diseases. | 49 | |
| 14700934974 | Density independent factors | Constant proportion of the population is affected regardless of population density. Tend to be abiotic components. Do not directly regulate population size. Natural disasters, fires, hurricanes, earthquakes, meteors, likelihood of death has nothing to do with population size. | 50 | |
| 14700934975 | Stable population change | Fluctuates slightly above and below carrying capacity as a population levels off. | 51 | |
| 14700934976 | Irruptive population change | Populations explode and then crash to a more stable level. Members of populations which exceed their resources will die unless they adapt or move to an area with more resources. Malthusian growth - population explosions followed by population crashes. Malthus concluded human populations send to grow until they exhaust their resources and then crash. |  | 52 |
| 14700934977 | Cyclic population change | Populations fluctuate and regular cyclic or boom-and-bust cycles. Population sizes often vary in regular cycles when the predator and prey populations are controlled by the scarcity of resources. |  | 53 |
| 14700934978 | Irregular population change | Erratic changes in possibly due to chaos or drastic change. | 54 | |
| 14700934979 | Reproductive patterns: opturnists and competitors | Large number of smaller offspring with little parental care (r-selected species). Fewer, larger offspring with higher invested parental care (K-selected species). | 55 | |
| 14700934980 | r-Selected Malthusian strategies | Short life, rapid growth, early maturity, many small offspring, little parental care, little investment in individual offspring, adapted to unstable environment, pioneers, colonizers, niche generalists, prey, regulated mainly by extrinsic factors, low trophic level. |  | 56 |
| 14700934981 | K-selected logistic strategies | Long life, slower growth, late maturity, fewer large offspring, high parental care and protection, high investment in individual offspring, adapted to stable environment, later stages of succession, niche specialists, predators, regulated mainly by intrinsic factors, high trophic level. | 57 | |
| 14700934982 | Survivorship curve | The way to represent the age structure of a population. The populations of different species vary in how long individual members typically live. Type I - late loss population live to an old age. Type II - constant loss population die at all age. Type III - most members of early loss population, die at young ages. |  | 58 |
| 14700934983 | Survivorship curve patterns | Full physiological life span, probability of death unrelated to age, mortality peaks both early and late in life, mortality peaks early in life. | | 59 |
