Test 2 Flashcards
What is ecology?
The study of relationships between organisms and environment
What is organismal ecology?
The study of an organism’s relationship with its environment (biotic and abiotic)
What is population ecology?
The study of interactions between members of the same species.
Define an abiotic factor and give some examples.
Non-living physical and chemical elements. Ex: water, air, soil, sunlight, minerals, etc.
Define a biotic factor and give some examples.
Living organisms. Ex: animals, plants, fungi, etc.
Define population
Groups of individuals of the same species in one place
What are the 3 characteristics of a population?
- Range/area
- Pattern of spacing of individuals
- Change in size through time
Define density-dependent factors and give some examples.
Population regulation where the denser a population is, the greater its mortality rate (negative feedback)(often biotic)
Ex: Predation, inter- and intraspecific competition, accumulation of waste, diseases, etc.
Define density-independent factors and give some examples.
Population regulation where the population is influenced no matter what its density is.
Ex: weather, natural disasters, pollution, and other chemical/physical conditions. (often abiotic)
What is population demography, and how is it done?
-The quantitative study of populations to see how populations change size over time.
-Populations are broken down into parts, and birth and death rates of a specific age are considered.
Population growth is most influenced by the number of what?
Females
What are generation times?
The average interval between an individual’s birth and its offspring’s birth. (shorter generation times mean an increase in size more quickly.)(larger organisms have longer generations times normally)
What is a Cohort?
Group of individuals of the same age.
What is Fecundity?
Number of offspring produced in a standard time
What is mortality?
Number of individuals removed from the population.
What is the mortality rate formula?
dx/nx (number of deaths during time period/number alive at the start of a time period)
Define survivorship and survivorship curve.
-percent of the original population surviving to a given age.
-Graph of number of individuals surviving at each age interval.
What is a type 1 curve species?
The species have a small number of offspring and provide lots of parental care to make sure those offspring survive. This leads to few offspring that survive for a long time. (humans)
What is a type 2 curve species?
Organisms of this species die more or less equally at each age interval. (birds)
What is a type 3 curve species?
The species have lots of offspring at once but don’t provide much care for the offspring. This leads to a high amount of offspring mortality, with few surviving.
What do life tables show?
The probability of survival and reproduction through a cohort’s life.
Which of the following components is NOT typically used to construct a life table?
Birth rates, death rates, survival rates, or fertility rates.
fertility rates
Populations often remain what regardless of number of offspring born?
The same size.
What is the difference between Immigration and Emigration?
Immigration: individuals entering a population
Emigration: individuals leaving a population
What is a carrying capacity?
(k): The maximum number of individuals that an environment can support.
What is a J curve?
The curve of exponential growth in a population. There are no checks on the population’s growth.
What is logistical growth?
The growth of a population as it reaches its environment’s carrying capacity. Its curve will resemble a S shape.
What type of growth do humans have?
exponential
What is an ecological footprint?
The amount of productive land required to support an individual at the standard of living of a particular population through the course of his/her life.
What is a dominant species?
The most abundant species.
What is a keystone species?
The most influential species with respect to trophic levels.
What is a foundation species?
A species that allows other species to inhabit an area by altering the environment.
What is community ecology?
The study of interacting populations of species living within a particular area or habitat.
What is Intraspecific competition?
Competition within a species.