Population ecology, human population growth community ecology, co-evolution, ecological succession, ecosystems, biogeochemical cycles, biomes, and human impact on the biosphere.
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| 1062614676 | Population | A group of individuals of the same species living in the same area. | 1 | |
| 1062614677 | Community | A group of populations living in the same area. | 2 | |
| 1062614678 | Ecosystem | The interrelationships between the organisms in a community and their physical environment. | 3 | |
| 1062614679 | Biosphere | It includes all the regions of the earth that contain living things. | 4 | |
| 1062614680 | Habitat | The type of place where it usually lives. It includes the other organisms that live there as well as the physical and chemical characteristics of the environment. | 5 | |
| 1062614681 | Niche | All the biotic and abiotic resources in the environment used by an organism which define where it can live. *If niches overlap for two species, they will compete. - The more they overlap, the greater the competition between the two species. | 6 | |
| 1062614682 | Population Density | The total number of individuals per area or volume occupied. | 7 | |
| 1062614683 | Dispersion | How individuals in a population are distributed. It could be clumped, uniform, or random. | 8 | |
| 1062614684 | Age Structure | The description of the abundance of individuals of each age. | 9 | |
| 1062614685 | Survivorship Curves | The description how mortality of individuals in a species varies during their lifetimes. | 10 | |
| 1062614686 | Type I | A survivorship curve in which most individuals survive to middle ages. After that age mortality is high. | 11 | |
| 1062614687 | Type II | A survivorship curve in which the organism's life is random. | 12 | |
| 1062614688 | Type III | A survivorship curve in which most individuals die young with only a few surviving to reproductive age and beyond. | 13 | |
| 1062614689 | Biotic Potential | The maximum growth rate of a population under ideal conditions, with unlimited resources and without any growth restrictions. | 14 | |
| 1062614690 | Factors of Biotic Potential | Age at reproductive maturity, clutch size (the number of offspring at each reproductive event), frequency of reproduction, reproductive lifetime, and survivorship of offspring to reproductive maturity. | 15 | |
| 1062614691 | Carrying Capacity | The maximum number of individuals of a population that can be sustained by a particular habitat. *This happens when r=0, the population stops growing and it reaches equilibrium. | 16 | |
| 1062614692 | Limiting Factors | Elements that prevent a population from attaining its biotic potential. | 17 | |
| 1062614693 | Density-Dependent | A type of limiting factor whose limiting effect becomes more intense as the population density increases. Gives rise to the S-shaped logistic growth curve. *Happens after growing exponentially for a while, but growth rate has to decrease as the environment becomes more and more crowded. *Can be caused by resource competition or biotic interactions. (Greater crowding can lead to disease, or to the attraction of more predators) | 18 | |
| 1062614694 | Density-Independent | A type of limiting factor that occurs independently of the density of the population which includes natural disasters and extremes of climate. | 19 | |
| 1062614695 | Exponential Growth | When the reproductive rate is greater than zero and when plotted it rises quickly forming a J-shaped curve. | 20 | |
| 1062614696 | Logistic Growth | When limiting factors restrict the size of the population to the carrying capacity of the habitat and when plotted it stabilizes forming a S-shaped, or sigmoid, curve. | 21 | |
| 1062614697 | Population Cycles | Fluctuations in population size in response to varying effects of limiting factors. | 22 | |
| 1062614698 | R-Selected Species | This species exhibits rapid growth. This type of strategy is characterized by opportunistic species. | 23 | |
| 1062614699 | K-Selected Species | This species' population size remains relatively constant at the carrying capacity. | 24 | |
| 1062614700 | Abiotic Factors | The non-living parts of an organism's habitat. SWATS: Soil, Water, Air, Temperature, and Sunlight. | 25 | |
| 1062614701 | Biotic Factors | The living parts of an ecosystem. Usually include: producer, consumers, decomposers, and human influence. | 26 | |
| 1062614702 | Ernst Haeckel's definition of Ecology | The comprehensive science of the relationship of the organism to the environment. Invented the word "ecology". | 27 | |
| 1062614703 | C. J. Krebs' definition of Ecology | The scientific study of the interactions that determine the distribution and abundance of organisms | 28 | |
| 1062614704 | Mutualism | A relationship between two species in which both species benefit. Exp: like the bacteria in our gut that helps us break down our food. | 29 | |
| 1062614705 | Competition or Interspecific Competition | (-,-) A common demand by two or more organisms upon a limited supply of a resource; for example, food, water, light, space, mates, nesting sites. It may be intraspecific or interspecific. *If there is competition for a limiting resource, growth rates of both competitors will be reduced. *Gives way to resource partitioning, as natural selection favors individuals that do not compete. | 30 | |
| 1062614706 | Consumer Resource | (-,+) The consumer benefits while the consumed organism - the resource - loses. *Includes predation, herbivory, and parasitism, & pathogens. | 31 | |
| 1062614707 | Commensalism | (+,0) An interaction where one participant benefits, while the other is unaffected. | 32 | |
| 1062614708 | Amensalism | (-,0) An interaction between species when one species if harmed while the other is unaffected. *Often the harm is accidental. Exp: Elephants crush plants and insects while moving through a forest. | 33 | |
| 1062614709 | Parasitism | A relationship in which one organism lives on or in a host and harms it. | 34 | |
| 1062614710 | Predation | An interaction between species in which one species, the predator, eats the other, the prey. | 35 | |
| 1062614711 | Per Capita Growth Rate | The difference between per capita birth rate and per capita death rate and represents the average individual's contribution to total population growth rate. *Delta (N) / Delta (T) | 36 | |
| 1062614712 | BD Model | The number of individuals in a population at some time in the future = the number now + the number that are born - the number that die. * N(t + 1) = N(t) + B - D | 37 | |
| 1062614713 | Evolutionary Arms Race | A form of coevolution in which the species involved each evolve countermeasures to the adaptations of the others; most often associated with host - pathogen and predator - prey coevolution. | 38 | |
| 1062614714 | Cheating | In a mutualistic relationship, the potential for one partner to acquire resources from the other partner without returning the mutualistic act. | 39 | |
| 1062614715 | Coevolution | Evolutionary processes in which an adaptation in one species leads to the evolution of an adaptation in a species with which it interacts. | 40 | |
| 1068783448 | Topography | The variations in the elevation of Earth's surface that form, for example, mountains & valleys. | 41 | |
| 1068783449 | Species Composition | The particular mix of species that a community contains and the relative abundances of those species. | 42 | |
| 1068783450 | Biome | A distinct physical environment that is inhabited by ecologically similar organisms with similar adaptations. | 43 | |
| 1068783451 | Succession | The gradual, sequential series of changes in the species composition of a community following a disturbance. | 44 | |
| 1068783452 | Ecological Transition | After some types of disturbance the original community is not reestablished, instead it becomes a distinctly different community. | 45 | |
| 1068783453 | Trophic Interactions | The consumer-resource relationships among species in a community. | 46 | |
| 1068783454 | Primary Producers | They convert solar energy into a form that can be used by the rest of the community. Aka autotrophs. | 47 | |
| 1068783455 | Autotrophs | Self feeders... they make their own food. | 48 | |
| 1068783456 | Heterotrophs | Species that obtain energy by breaking apart organic compounds that have been assembled by other organisms. (Herbivores) | 49 | |
| 1068783457 | Primary Consumers | Heterotrophs that dine on primary producers... aka herbivores. | 50 | |
| 1068783458 | Secondary Consumers | Primary carnivores... those that consume herbivores. | 51 | |
| 1068783459 | Tertiary Consumers | Secondary carnivores... those that consume primary carnivores. | 52 | |
| 1068783461 | Trophic Levels | The feeding positions: primary producers and primary, secondary, and tertiary consumers. A group of organisms united by obtaining their energy from the same part of the food web. | 53 | |
| 1068783463 | Omnivores | They feed on both plants and animals. (feed from multiple trophic levels.) | 54 | |
| 1068783464 | Decomposers/detritivores | Feed on waste products or dead bodies of organisms... Largely responsible for the recycling of materials within ecosystems. They break down organic matter into inorganic components that primary producers can absorb. | 55 | |
| 1068783465 | Gross Primary Productivity | Energy that primary producers capture and convert to chemical energy during gnome period of time. | 56 | |
| 1068783466 | Net Primary Productivity | Energy that primary producers have produced during that period of time. | 57 | |
| 1068783467 | Ecological Efficiency | The overall transfer of energy from one trophic level to the next. On average the total biomass of each trophic level is about one-tenth that of the level it feeds on. | 58 | |
| 1068783468 | Trophic Cascade | A series of changes in the population sizes of organisms at different trophic levels in a food chain, occurring when predators at high trophic levels indirectly promote populations of organisms at low trophic levels by keeping species at intermediate trophic levels in check. Trophic cascades may become apparent when a top predator is eliminated from a system. (yosemite wolves). | 59 | |
| 1068783469 | Species richness | The number of species in the community. | 60 | |
| 1068783470 | Species evenness | The distribution of species' abundances. | 61 | |
| 1068783471 | Island Biogeography | Accounts for island diversity patterns... The study of rates of colonization and extinction of species on islands or other isolated areas based on size, shape, and distance from other inhabited regions | 62 | |
| 1068783472 | Ecosystem services | Processes by which ecosystems maintain resources that benefit human society. | 63 | |
| 1068886236 | Convergent Evolution | Process by which unrelated organisms independently evolve similarities when adapting to similar environments. Tends to happen in biomes where animals develop similar natural selection. | 64 | |
| 1068886237 | The Nearshore regions of lakes and oceans | Littoral (lakes) , Intertidal or Littoral (Oceans) ... Shallow, affected by wave action, periodically exposed to air by fluctuations in water level. | 65 | |
| 1068886238 | Photic Zone | The region of lakes and oceans that is penetrated by light and therefore supports photosynthetic organisms. | 66 | |
| 1068886239 | The Open-Water zones | Limnetic zone (lakes) , Pelagic zone (oceans) | 67 | |
| 1068886240 | Aphotic Zone | In bodies of water, the region below the reach of light. | 68 | |
| 1068886241 | Benthic Zone | The lake bottom or ocean floor. | 69 | |
| 1068886242 | Abyssal Zone | The deepest parts of the ocean. Where there are very high pressures, low oxygen levels, and cold temperatures. | 70 | |
| 1068886243 | Biogeographic regions | Six continental-scale areas... each region encompasses multiple biomes and contains a distinct assemblage of species, many of which are phylogenetically related. | 71 | |
| 1068886244 | Biotic Interchange | Continued movements of continents have more recently eliminated some barriers to dispersal and have caused mixing of species. | 72 | |
| 1092043832 | Geographic Range | Region in which a species is found. | 73 | |
| 1092043833 | Habitat Patches | "Islands" of suitable habitat separated by areas of unsuitable habitat. | 74 | |
| 1092043834 | Life history | The time course of essential events during an average individual's life like .... growth and development, dispersal, reproduction, death. | 75 | |
| 1092043835 | Fecundity | Average number of offspring each individual produces at those life stages or ages. | 76 | |
| 1092258428 | Life-History Tradeoffs | Negative relationships among growth, reproduction, and survival. Exp: If you are likely to die young, it makes sense to invest in early reproduction. | 77 | |
| 1092258429 | Why do humans appear to break the rules for density dependence in population growth? | Vaccines, Antibiotics, Better sanitation, "Green Revolution", and technological advances have raised carrying capacity by increasing food production and improving health. | 78 | |
| 1092258430 | Conservation and Sustainability | Key priorities for the 21st century... as 20th century population expansion has led to climate change and ecosystem degradation. | 79 | |
| 1092258431 | Natural Experiment | When a natural process perturbs the ecosystem dramatically, so ecologists can learn by watching how the ecosystem responds. Exp: volcano eruption, flood, epidemic. | 80 | |
| 1092258432 | "Anthropocene" | (the Age of Humans)... human-dominated ecosystems (croplands, pasture, cities and towns) now cover ~50% of Earth's land area. *These ecosystems are more uniform than natural ones, becoming homogeneous. | 81 | |
| 1092258433 | Human activities that increase extinction risk | • Habitat destruction, fragmentation and alteration • Over-harvesting wild populations • Pollution • Introduction of invasive species • Climate change | 82 | |
| 1092258434 | Interspecific interactions | Interactions between individuals of different species, which can be beneficial (+), detrimental (-), or neutral (0) to each species. | 83 | |
| 1092258435 | Intraspecific Competition | Can lead to density dependence, when the per capita growth rate decreases due to competition for resources with individuals of the same species. | 84 | |
| 1092258436 | If an individual's fitness exceeds that of another... | then the frequency of that individual's traits will increase. | 85 | |
| 1092258437 | Rarity Advantage | Intraspecific competition must be stronger than interspecific competition... and a species gains a growth advantage when it is at a low density and its competitor is at a high density. *The result is coexistence. | 86 | |
| 1092258438 | Resource Partitioning | If differences in resource use are sufficiently large, competing species can coexist. *Differences between species in their use of resources causes individuals to have a larger effect on the resources available to another of the same species than to an individual of another species. | 87 | |
| 1092258439 | Competitive Exclusion | When both species used the exact same resource, the more efficient species would win. *Two species with the exact same niche cannot co-exist in the same place at the same time. One must out do the other. | 88 | |
| 1092258440 | Condition for Coexistence | For coexistence to be possible, INTRAspecific competition must be stronger than INTERspecific competition. *Then each species grows better when it is rare than when it is abundant (rarity advantage). | 89 | |
| 1092258441 | Fundamental Niche | The conditions tolerated and the resources used when predators are not around. (100% ... all is yours) | 90 | |
| 1092258442 | Realized Niche | The range of conditions tolerated or resources used when competitors are present (not able to use all resources since you are limited). | 91 | |
| 1092258443 | Prey/Predator Abundance | Lots of prey = lots of predators. Low prey = low amount of predators. *Exp: Infectious diseases show Predator-Prey Cycles. Consumer:infectious disease. Resource: susceptible (non-immune) hosts. | 92 | |
| 1093617613 | Species Turnover | Some species drop out and new ones appear. *Some or all of the species can be wiped out, and environmental conditions are changed. | 93 | |
| 1093617614 | What can cause communities to change over time? | Extinction and colonization, Disturbance, Climate change. | 94 | |
| 1093617615 | Better Colonizers | They invest in early reproduction, many offspring, and high dispersal, but have short life expectancy. | 95 | |
| 1093617616 | Better Competitors | They invest in growth and defense, and have fewer, later offspring and long life expectancy. | 96 | |
| 1097658328 | Invasive Species | An exotic species that reproduces rapidly, spreads widely, and has negative effects on the native species of the region to which it had been introduced. | 97 | |
| 1102689378 | Principal of Allocation | The idea that a unit of some resource acquired by an organism can be used for only one function at a time, meaning that resources must be divided among competing functions. | 98 |
