population distribution and abundance and life histories Flashcards
(29 cards)
what is a population
a group of individuals of the same species that live within a certain area and interact with one another
how can abundance be reported
population size
density
what study was used to show that despite climatic conditions being similar insect abundance varies
a 6 year study of 23 species that feed on goldenrod
define dispersal
a process in which individuals move away from a population in which they were born to another locatin where they settle and reproduce
why can it be difficult to count individuals
it is hard to determine what an individual actually is, for example some trees produce clones or runners so count as one individual
what is a unitary organism
organisms which are highly determinate with fertilsiation, birth, gorwth etc
what is a modular organism
organisms which are unpredicatble forms and growth and development is according to the environment
what limits distributions
habitat suitability
historical factors
abiotic factors
what restricts the barnacle semibalanus balanoides
temperature and competition from other species
give an example of how dispersal abilities and geologic events affects the distributi0on of species
polar bears evolved from brown bears in the artic but are not found in the artic due to the inability to disperse through tropical regins
what is geographic range
includes areas occupied by all life stages of a species, some species migrate long distances between summer and winter habitats
what is a regular spatial arrangement
individuals are evenly spaces
what is a random spatial arrangemnet
individuals are scattered randomly
what is a clumped spatial arrangement
indiivudals are clumped together
what determines dispersino patterns
the distribution of resources
what are area based counts used for
to estimate the abundance of immobile organisms
40,10,70,80 and 50 beetles are counted in five 10 by 10 quadrats how many per m sqauered
40+10+70+80+50/5 then divide by 0.02= 5000
what method is used to estimate the abundance of mobile species
mark recapture mthods
what is the lincon index
M/N=R/C
m= marked individuals
n= total pop size
R= recaptured
c- captured
what are life histories
a record of events relating to growth development reproduction and survival of an organism
define phenotypic plasticity
where one genotype may produce different phenotypes under different environmental conditions producing different morphs of the same species
define polyphenism
a single genotype produces several distinct morphs
what does sexual reproduction result in
genetic variation
isogamy = equal gametes
anisogamy = unequal gamets
define semelparous
a single distinct reproductive period then death
