Test 2 Flashcards
Define Population
Group of individuals of the same species that live in a given area.
What is distribution?
The geographic area where individual species are present.
3 factors that can influence the distribution and abundance of organisms?
Habitat suitability
Historical factors
Dispersal
What is geographic range?
The entire geographic region over which a species is found.
Why would a species geographic range be poorly understood? For example, little was know about the monarch butterfly’s range for this region.
Because a species life range also includes all of it’s stages of life, which can be hard to study. Little was know about the monarch until it was discover where they migrated in the winter.
Unsuitable habitats within a species geographic range lead to _________
Populations having patchy distributions.
In natural populations which is more common: clumped dispersion , regular dispersion, or random dispersion?
Clumped
What affects dispersion patterns?
Resources, competition, individual behavior, and dispersal.
Are based counts are used to estimate populations of_______ organisms.
Immobile
In what estimation approach are organisms counted in a series of sample plots or quadrants and the resulting numbers are used to estimate population size?
Area-based counts.
What is an ecological niche?
The abiotic and biotic conditions that a species needs to grow, survive, and reproduce
What is a niche model ?
A tool that predicts a species geographic distribution based on the environmental conditions the species is known to occupy.
Habitat mosaics cause clumped dispersion patterns. Name species that exhibit this.
Clematis fremontii and the red kangaroo, fl scrub jay, fl sand skink.
What is a population?
Individuals of one species in a specified area that interact with one another.
What is Survival rate?
Sx
The chance an individual of age x will survive to be x+1.
What is survivor ship?
Lx
The proportion of individuals that survive from birth to age x.
What is fecundity?
The average number of offspring produced by a female while she is of age x.
In a type one survivorship curve what age groups have the highest survival rate? What kind of species follow this pattern?
New burns, juveniles, and young adults have high survival rates.
People and elephants
Birds that have a constant chance of survival from one age to the next exhibits what type of survivorship curve?
Type 2
In type 3 survival ship curves, which individuals have the highest chance of survival?
Adults
Typical of species that produce large number of young.
European starling has a _____ distribution?
World wide.
Clematis fremontii has a limited distribution and is _______ to ______.
Endemic, U.S
Florida scrub jay
Very limited distribution. Endemic to fl
Aphelocoma coerulescens.
Florida sand skink
Very very limited deist runtime. Endemic to a few counties
Noeseps reynoldsi.
Absolute abundance.
Population size and density.
What is population structure and what are it’s characteristics?
The arrangement of individuals of a pop.
- Abundance
- Spacing
- Demography
What is a survey? And what are some examples?
Estimation of population size by sampling a portion.
- Plot sampling
- Point counts
- Mark recapture
- Transect.
Causes of clumped dispersion patterns :
- unevenly distributed resources
- social organisms
- dispersal limited
Causes of uniform distribution:
- competition for resources
- territoriality
Dispersion at community level is affected by:
- mutualism
- predation
- competition
- territoriality
What is the dispersion pattern when the the mean = the variance?
random
What is the relation ship on the mean and variance for a clumped pattern?
Variance > mean
When variance < mean what dispersal pater is exhibited?
Uniform
Both the creosote and saguaro are found in _____ areas and are limited by ________. Which plant is limited by temperature? Which plant has a larger distribution?
Dry, moisture. Saguaro can’t tolerate freeze for > 36 hours.
Creosote has a larger distribution.
This an example how abiotic facts determine abundance and distribution.
What type of environment to fl scrub jays live?
In open areas where there is less dense scrub due to burns.
Define scrub
Xeric (very dry) sandy areas dominated by several stunted species of oaks.
S. Blanoides are a species of barnacles who’s distribution is limited by:
- temperature (to the north)
- competition w/ other barnacles ( to the south)
Habitat mosaics are cause by variations ______ and _____. Habitat mosaics cause ______ dispersion patterns. Example?
biotic, and abiotic factors, clumped.
Clematis fremontii, fl scrub jay, fl sand skink.
What is a life table?
Summary of ages specific survival probabilities and fecundity rates.
What does a life table tell us?
- Chance of surviving to next time unit
- Life expectancy
- Reproductive output at a specific age
What can determine reproductive output?
Size, age, life strategies
What are the two ways in which class specific survival and fecundity data can be collected and summarized?
Cohort life table, and static life table