Community Ecology

• Community ecology: study of interactions that determine distribution and abundance of pops in communities
• Competition (-/-): A situation in which two or more organisms compete for the same resources that are limited.
• Intraspecfic: fighting between same species
• Interspecfic: fighting between different species
• competitive exclusion: when one species kicks out another species
• Fundamental Niche : one species occupies it with ideal circumstances for its survival and reproduction
• Realized Niche: species was kicked out and found another niche to survive in, uses resources and actual interactions
• Character displacement: two different niche with species that don't compete with each other
• Species with identical niches cannot coexist
• Species with similar niche can coexist but one species may exclude other from its fundamental niche into a realized niche
• Predation (+/-): prey eats prey and results in an evolutionary "arm" race where both co-evolve
• Both prey and predator evolve to survive and reproduce
• Multiple types of adaption for prey to protect themselves: cryptic, aposematic, batesian, mullerian, behavioral, mechanical, and chemical
• Cryptic: prey has adapted camouflage to protect itself
• Aposmatatic: prey has adapted bright/colorful coloration to warn predators
• Bastesian Mimicry: defenseless organism mimicking defensive organism. Defensive species must be higher in population density
• Mullerian mimicry: species mimic each other but are all dangerous, prey learn coloration of one and avoids all
• Behavioral defenses: fleeing or living in groups, camouflage, mimicry
• Mechanical defenses: physical attribute that deters
• Chemical defense: smell/toxin that deters prey
• Symbiosis: intimate, long term relationship between 2 or more species
• Three types of symbiosis: mutualism, commensalism, and parasitism
• Paratism (+/-): parasite benefits and host can be harmed
• Mutualism ( +/+): both partners benefit and depend on each other
• Commensalism (+/0): one organism benefits while other neither helped or harmed
• Dominant species: most abundant or highest biomass
• Keystone Species: usually not abundant, but have strong influence on community structure
• Plants have two types of adaptations: mechanical defense and chemical defense.
• Species Richness: The number of different species in a community.
• Relative abundance: proportion each species represents of all individual in community
• Higher diversity in communities: community more productive, better able to withstand and recover from stress, and are more resistant to invasive species
• Ecological succesion: continuous process of community deveoplement overtime
• Primary Succession: habitat that was not previously inhabitant( bare rock)
• Secondary Succession: existing community cleared by disturbance that leaves soil intact