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| 5043003318 | Community | Assembly of populations of various species living close enough for potential interaction. | 0 | |
| 5043014902 | Interspecific Interactions | Relationships between species in a community. EXAMPLE: Competition, Predation, Herbivory, Symbiosis (parasitism, mutualism, and commensalism), and facilitation. The effects of these can be summarized as positive (+), negative (-), or no effect (0). (Concept 54.1: Community interactions are classified by whether they help, harm, or have no effect on the species involved.) |  | 1 |
| 5043032712 | Interspecific Competition | (-/- interaction) occurs when species compete for a resource in short supply. (Concept 54.1: Community interactions are classified by whether they help, harm, or have no effect on the species involved.) | 2 | |
| 5043040868 | Competitive Exclusion | Local elimination of a competing species. The competitive exclusion principle states that two species competing for the same limiting resources cannot co exist in the same place. (Concept 54.1: Community interactions are classified by whether they help, harm, or have no effect on the species involved.) |  | 3 |
| 5043050462 | Ecological Niche | Sum of a species' use of biotic and abiotic resources. Can also be thought of as an organism's ecological role. Ecologically similar species can live in the same community if there is at least one significant difference in their niche. (Concept 54.1: Community interactions are classified by whether they help, harm, or have no effect on the species involved.) | 4 | |
| 5043061422 | Resource Partitioning | Differentiation of ecological niches, enabling similar species to coexist in a community. (Concept 54.1: Community interactions are classified by whether they help, harm, or have no effect on the species involved.) |  | 5 |
| 5043070571 | Fundamental Niche vs Realized Niche | A Fundamental Niche is the niche potentially occupied by that species, while the Realized Niche is the niche actually occupied by that species. These can differ as a result of competition. (Concept 54.1: Community interactions are classified by whether they help, harm, or have no effect on the species involved.) |  | 6 |
| 5043082016 | Character Displacement | Tendency for characteristics to be more divergent in sympatric (geographical closer) populations of two species than in allopatric (separate geographical areas) populations of the same two species. EXAMPLE: variation in beak size between populations of two species of Galápagos finches. (Concept 54.1: Community interactions are classified by whether they help, harm, or have no effect on the species involved.) |  | 7 |
| 5043108022 | Predation | (+/- interaction) one species (predator) kills and eats another species (prey). The prey can develop defenses, such as hiding, fleeing, forming herds, self-defense, alarm calls, or mechanical or chemical defenses. EXAMPLE: a chemical defense would be a skunk's spray, a mechanical defense would be a porcupines spikes. (Concept 54.1: Community interactions are classified by whether they help, harm, or have no effect on the species involved.) | 8 | |
| 5043138013 | Aposematic Coloration | The bright warning coloration shown by animals with effective chemical defense. EXAMPLE: poison dart frog. (Concept 54.1: Community interactions are classified by whether they help, harm, or have no effect on the species involved.) |  | 9 |
| 5043147428 | Cryptic Coloration | Also known as camouflage, makes prey difficult to spot. EXAMPLE: canyon tree frog. (Concept 54.1: Community interactions are classified by whether they help, harm, or have no effect on the species involved.) |  | 10 |
| 5043155651 | Batesian Mimicry | A palatable (harmless) species mimics an unpalatable (harmful) model. EXAMPLE: The nonvenomous hawkmoth larva imitates the venomous green parrot snake. (Concept 54.1: Community interactions are classified by whether they help, harm, or have no effect on the species involved.) |  | 11 |
| 5043173983 | Müllerian Mimicry | Two or more unpalatable (harmful) species resemble each other. EXAMPLE: Yellow jacket and the cuckoo bee. (Concept 54.1: Community interactions are classified by whether they help, harm, or have no effect on the species involved.) |  | 12 |
| 5043185908 | Herbivory | (+/- interaction) an interaction in which a herbivore eats parts of a plant or alga. This has led to evolution of plant mechanical and chemical defenses and adaptations by herbivores. (Concept 54.1: Community interactions are classified by whether they help, harm, or have no effect on the species involved.) | 13 | |
| 5043197365 | Symbiosis | Relationship where two or more species live in direct and intimate contact with one another. (Concept 54.1: Community interactions are classified by whether they help, harm, or have no effect on the species involved.) | 14 | |
| 5043201020 | Parasitism | (+/- interaction) one organism, the parasite, gets nourishment from another organism, the host, who is harmed in the process. Parasites that live within the body of their host are called Endoparasites. Parasites that live on the external surface of their host are Ectoparasites. Most parasites have a number of hosts. They can significantly affect their host population. (Concept 54.1: Community interactions are classified by whether they help, harm, or have no effect on the species involved.) | 15 | |
| 5043301067 | Mutualism | (+/+ interaction) interspecific interaction that benefits both species. Can be Obligate, where one species cannot survive without the other, or Facultative, where both species can survive alone. EXAMPLE: A bird eating the food out from a crocodile's teeth. (Concept 54.1: Community interactions are classified by whether they help, harm, or have no effect on the species involved.) |  | 16 |
| 5043338071 | Commensalism | (+/0 interaction) one species benefits and the other is neither harmed nor helped. These are hard to document in nature, because any close association between species likely affects both. EXAMPLE: Cattle Egrets and Cattle. The cattle egrets follow the cattle around and eat the bugs they kick up. (Concept 54.1: Community interactions are classified by whether they help, harm, or have no effect on the species involved.) |  | 17 |
| 5043425487 | Facilitation | (+/+ or 0/+) an interaction in which one species has positive effects on another species without direct and intimate contact. EXAMPLE: The black rush makes the soil more hospitable for other plant species. (Concept 54.1: Community interactions are classified by whether they help, harm, or have no effect on the species involved.) | 18 | |
| 5043525736 | Species Diversity | The variety of organisms that make up the community. Has two components: Species Richness is the number of different species in the community, and Relative Abundance is the proportion each species represents of all the individuals in the community. (Concept 54.2: Diversity and trophic structure characterize biological communities.) |  | 19 |
| 5043549904 | Shannon Diversity Index | Two communities can have the same species richness but a different relative abundance. Diversity can be compared using this index, where A, B, C...are the species, p is the relative abundance of each species, and the ln is the natural logarithm. Molecular tools can be used to help determine microbial diversity. (Concept 54.2: Diversity and trophic structure characterize biological communities.) |  | 20 |
| 5043611301 | Biomass | Total mass of all organisms. (Concept 54.2: Diversity and trophic structure characterize biological communities.) | 21 | |
| 5043612870 | Invasive Species | Organisms that become established outside their native range. (Concept 54.2: Diversity and trophic structure characterize biological communities.) | 22 | |
| 5043620271 | What are the benefits of communities with higher diversities? | -More productive; produce more biomass -More stable in productivity -Better able to withstand and recover from environmental stresses -More resistant to invasive species. (Concept 54.2: Diversity and trophic structure characterize biological communities.) | 23 | |
| 5043632531 | Trophic Structure | The feeding relationships between organisms in a community. (Concept 54.2: Diversity and trophic structure characterize biological communities.) |  | 24 |
| 5043642530 | Food Chains | They link trophic levels from producers to top carnivores. (Concept 54.2: Diversity and trophic structure characterize biological communities.) |  | 25 |
| 5043648676 | Food Web | Branching food chain with complex trophic interactions. They can be simplified by grouping species with similar trophic relationships into broad functional groups, or isolating a portion of a community that interacts very little with the rest of the community. (Concept 54.2: Diversity and trophic structure characterize biological communities.) |  | 26 |
| 5046734876 | Energetic Hypothesis | Suggests that length of food chains in food web is limited by inefficient energy transfer. Only about 10% of energy stored in organic matter at each trophic level is converted to organic matter at the next trophic level. (Concept 54.2: Diversity and trophic structure characterize biological communities.) |  | 27 |
| 5049336434 | Dominant Species | Those that are most abundant or have the highest biomass. One hypothesis suggests that these species are most competitive in taking resources, and another hypothesis states that they are most successful at avoiding predators. Invasive species, which are typically introduced to a new environment by humans, may become dominant because they lack predators or disease. One way to discover the impact of a dominant species is to remove it. (Concept 54.2: Diversity and trophic structure characterize biological communities.) | 28 | |
| 5049365565 | Keystone Species | Exert strong control on a community by their ecological roles, or niches. They are not necessarily abundant in a community. (Concept 54.2: Diversity and trophic structure characterize biological communities.) |  | 29 |
| 5049389319 | Ecosystem Engineers | Also known as foundation species, they cause physical changes in the environment that affect community structure. EXAMPLE: Beaver dams transform landscapes on a large scale. (Concept 54.2: Diversity and trophic structure characterize biological communities.) | 30 | |
| 5049403813 | Bottom-Up Model | Proposes a unidirectional (one way) influence from lower to higher trophic levels. N -->V -->H -->P In this case, presence or absence of mineral nutrients (N) controls plant (V) numbers, which control herbivore (H) numbers, which control predator (P) numbers. (Concept 54.2: Diversity and trophic structure characterize biological communities.) |  | 31 |
| 5049457913 | Top-Down Model | Also called a trophic cascade model, proposes that control comes from the trophic level above. N<-- V<-- H<-- P In this case, predators (P) limit herbivores (H), herbivores limit plants (V), and plants limit nutrient levels (N). (Concept 54.2: Diversity and trophic structure characterize biological communities.) |  | 32 |
| 5049489151 | Biomanipulation | Can help restore polluted communities. (Concept 54.2: Diversity and trophic structure characterize biological communities.) |  | 33 |
| 5049813883 | Disturbance | Event that changes a community, removes organisms from it, and alters resource availability. Types, frequency, and severity of disturbances change from community to community. High level of disturbance is the result of a high intensity and high frequency of disturbance. Low levels of disturbance can result from low frequency or low intensity of disturbances. (Concept 54.3: Disturbance influences species diversity and composition.) | 34 | |
| 5049828899 | Non-Equilibrium Model | Describes communities as constantly changing after being buffeted by disturbances. (Concept 54.3: Disturbance influences species diversity and composition.) | 35 | |
| 5049860586 | Intermediate Disturbance Hypothesis | Moderate levels of disturbance can foster greater diversity than either high or low levels of disturbance. High levels exclude many slow-growing species, and low levels allow dominant species to exclude less competitive species. EXAMPLE: The richness of invertebrate taxa was highest in streams with an intermediate intensity of flooding. (Concept 54.3: Disturbance influences species diversity and composition.) |  | 36 |
| 5049980812 | Ecological Succession | Sequence of community changes after a disturbance. (Concept 54.3: Disturbance influences species diversity and composition.) | 37 | |
| 5049984736 | Primary Succession | Occurs where no soil exists when succession begins. (Concept 54.3: Disturbance influences species diversity and composition.) | 38 | |
| 5050005242 | Secondary Succession | Begins in an area where soil remains after a disturbance. EXAMPLE: Abandoned agriculture land may return to its original state through secondary succession. (Concept 54.3: Disturbance influences species diversity and composition.) | 39 | |
| 5052892015 | What are the two key factors that affect a community's species diversity? | Latitude (species richness is great in the tropics and generally declines as it moves towards the poles, climate is probably the primary reason for the gradient) and area. (Concept 54.4: Biogeographic factors affect community diversity.) | 40 | |
| 5053047851 | Evapotranspiration | Evaporation of water from soil plus transpiration (evaporation of water from plant leaves basically) of water from plants. (Concept 54.4: Biogeographic factors affect community diversity.) | 41 | |
| 5053061276 | Species-Area Curve | Quantifies the idea that, all other factors being equal, a larger geographic area has more species. Can be described mathematically as shown in the picture, where S is the number of species, c is a constant, A is the area, and z represents how many more species should be found as habitat area increases. (Concept 54.4: Biogeographic factors affect community diversity.) |  | 42 |
| 5053097516 | Pathogens | Include disease-causing microorganisms, viruses, viroids, and prions, Ecological communities are universally affected by these. They can be extremely severe in a new habitat. EXAMPLE: Coral reef communities are being decimated by white-band disease. (Concept 54.5: Pathogens alter community structure locally and globally.) | 43 | |
| 5053122309 | Zoonotic Pathogens | Have been transferred from animals to humans. This transfer can be direct, or through an intermediate species called a vector. (Concept 54.5: Pathogens alter community structure locally and globally.) |  | 44 |
