Chapter 5: Biodiversity, Species Interactions, & Population Control
primary ecological succession
involves the gradual establishment of biotic communities in lifeless areas where there is no soil in a terrestrial ecosystem/no bottom sediment in an aquatic one
secondary ecological succession
occurs when an existing community has been cleared by some disturbance that leaves the soil intact
chemical warfare
predators/prey use toxins for attack/defense
environmental resistance
pressure on exponential growth, placed by limits in food, space, and other resources
coevolution
process by which two species evolve in response to changes in each other
interspecific competition
species compete for a limiting resource (-/-)
resource partitioning
the division of environmental resources by organisms living in the same area so that each group of organisms can occupy a different niche
How do communities and ecosystems respond to changing environmental conditions?
the structure and species composition of communities and ecosystems change in response to changing environmental conditions through a process called ecological succession
limiting factor principle
too much or too little of any abiotic factor can limit or prevent growth of a population of a species in an ecosystem, even if all other factors are at or near the optimal range of tolerance for the species
population change forumula
(births+ immigration) - (deaths+emigration) = population change
predation
an interaction in which one organism captures and feeds on another organism (+/-)
s curve
a curve that depicts logistic growth
j curve
a growth curve that depicts exponential growth
commensalism
a relationship between two organisms in which one organism benefits and the other is unaffected (+/o)
parasitism
a relationship in which one organism lives on or in a host and harms it (+/-)
mutualism
a symbiotic relationship in which both organisms benefit (+/+)
camoflauge
an adaptation that allows an organism to blend in with its environment - useful for predators and prey
ecological resilience
ecosystem is able to withstand changes in environmental pressure
ecological inertia
ecosystem is slow to change in response to environmental stress
How do species interact?
five types of species interactions a) competition b) predation c) parasitism d) mutualism e) commensalism affect the resource use and population sizes of the species in an ecosystem
carrying capacity
largest number of individuals of a population that a environment can support
What limits population growth?
no population can continue to grow indefinitely because of limitations on resources and because of competition among species for those resources
