Final Exam Flashcards
Define: Ecological Niche
The range of resources and conditions allowing the species to maintain a viable population, describes how an organism or population responds to the distribution of resources.
Define Ecosystem
An ecosystem is a geographic area where plants, animals and other organisms, as well as weather and landscapes, work together to form a system through their interactions
Define Population Abundance
The total number of individuals of a species or type present in a given area, ecosystem or particular habitat
Define high abundance
A species is considered abundant when it has a high population relative to the size of area it inhabits.
Population Density vs Population Abundance
Population abundance is the total number of individuals in a population, and population density is the number of individuals within a certain area
Define Population Density
Average number of individuals per unit area
Define Population Distribution
Describes how the individuals are distributed, or spread throughout their habitat (in response to favourable conditions)
(Clumped, random, uniform)
Define Population
Individuals of the SAME SPECIES inhabiting a defined space in a particular time
Define Geographic Range of a Population
Area encompassing all individuals/ populations of a species
Define the Law of Tolerance
The existence, abundance and distribution of a species in an ecosystem is determined by whether the levels od one or more physical/chemical factors fall within the tolerated range by those species
True or False: Two species can occupy the same niche indefinitely
FALSE
Important: Many species that appear to coexist in the same niche actually differ by tolerance to some environmental factor
They will have competititon for resources
True or False: Food availability influences habitat suitability
True
True or False:
Generalists have a smaller geographical range
False - LARGER
What is census?
A census is a study of every unit, everyone, or everything in a population.
Mark Re-Capture Equation
Mark Re-Capture Assumptions
- No marks are lost
- All individuals in the population have an equal probability of being captured
- The population is not increased by births or immigration between marking and recapture
- Marked and unmarked individuals die and emigrate in the same rates
What is the n-dimensional hypervolume of niche concept?
This is the Hutchinsonian Niche where the dimensions are the environmental conditions and resourcez, that define the requirements of an individual or a species population to persist.
Define Population Size
Countable quantity representing the number of individual organisms in a population.
What aspects of abundance do population density and population size measure?
Population Density measures the population abundance in a specific area
Population size gives the total number of inhabitants
If two species’ niches overlap, their habitats …
may or may not overlap which is dependent on other niche requirements.
If their habitats are overlapping, there could be competition between the two species.
What does a species’ niche encompass?
Both the physical environmental conditions it requires (like temperature or terrain) and the interactions it has with other species (predation or competition)
