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ch 13 pop growth and regulation - Coggle Diagram
ch 13 pop growth and regulation
pop grow rapid under good conditions
exponential growth model
growth rate=number of new indaviduals produce in an ammount of time - death indaviduals
intrensic growth rate=(r) highest per capita growth rate(born-dead/total)
Nt=Noe^rt(No current population, intrensic growth rate r, time t, e log 2.72, Nt future pop.)
j shaped curve
rate of growth at any time= dN/dt(change in pop over time)=rN
geometric growth model
Nt=No(lamed)^t
related logelamed=r
population doubling time
exponentialy= t=loge 2/r
geometricly= t=log e 2 /loge lamed
pop growth can be aff by density indapendint/dependent factors
density-indapendent= limit pop regardless of ensity natural disasters drought,
impacted by climate change more freeses and huracanes, fires
density dependent
negative density dependent=pop growth decreses as density increases
self thining curve=graph relationship that shows decrese in pop
positive density depend/ inverse density dependince= rate of pop growth increases as density increases
commonly in small populations and finding mates or ect parasites
log growth model incorperates density dependence.
carrying compacity=maximum population that can be supported by its enviroment(K)
dN/dt=rN(1-N/K)
s shaped curve
inflection point=pop reaches highest growth rate
life tables demonstate efect of age size and life hystory on pop growth.
age structure= porportion of indaviduals that occors in different age classses
baby booms= lots of kids
survivorship curves
tipe 1=low mortality earily in life and high later in life humans elephants
type 2= consistant ortality over age's squirls
tyoe 3=high moretality earily low moretality late in life (insects and plants that produce seeds in the hundreds oaks)
life tables=complation of class specific survival and fecundy data.oftin based on females
survining to next age class =(nx)x(sx)
of new offspring=(nx)x(sx)x(bx)
sx=survival rate n=population, b=births x=age (lx)=survivors
calculationg survivorship=lx l2=l1s1(second year)
net reproductive rate=total number of female offspring that we expect an average female to birth in her lifetime.
R0=E(lx)(bx)
generation time=average time between birth of an indavidual and the birth of offspring= T=(E(x(lx)(bx))/(E(lx)(bx))
intrensic rate of increase=(lamid or r)=lamid a =R(net reproductive rate)^1/T
pop grows>1 pop shring <1 R0
collecting data for life tables
cohort life table=group of indaviduals born at the same time then quantify survival and fecundy till last indavid dies
static life table quantify all data of all indaviduals for a single time interval.
dependent on global warming
from fossil records