Upgrade to remove ads
BIO 150 lecture 9
Terms in this set (62)
the expansion, decline, or maintenance of populations;
one of the most important areas of ecology as it holds the key to understanding and, hopefully, preventing the decline and extinction of endangered species, the control of pests, including parasites and pathogens, and the maintenance of economically and culturally important populations.
1. Dispersal can increase or decrease local population densities 2. Ongoing dispersal can join numerous subpopulations to form a metapopulation. 3. A survivorship curve summarizes the pattern of survival in a population. 4. The age distribution of a population reflects its history of survival, reproduction, and potential for future growth 5. A life table combined with a fecundity schedule can be used to estimate net reproductive rate (R0), geometric rate of increase (λ), generation time (T), and per capita rate of increase (r)
Key Concepts: 5
1. Dispersal can increase or decrease ____population densities.
(dispersal into the local population)
(dispersal out of the local population)
Passive (esp. plants)
distance traveled depends on the quality of the dispersal agent
Active (mobile animals)
young vs adults vs sub-adults; male vs female
Natal dispersal and Breeding dispersal
dispersal of active (mobile animals) (2)
Dispersal _______ during periods of population decline
Dispersers seek vacant habitat
distance depends on surrounding environment
Exploratory forays before leaving _____ site
1st uncontested site
Rule of dispersal: move to the __________ and no further
dispersing and sedentary
Organisms have __and _____ stages
Migration; evolutionary or environmental
dispersal with a return to the place of origin; in response to an ______ or_______ adaptation or pressure
Daily, seasonal (short- or long-range)
Only 1 return trip
(e.g. pacific salmon)
Only offsprings return
(e.g. monarch butterfly)
_____ populations are in the process of increasing their geographic range
climate change, to changing food supply
Range changes in response to ______ and ______
2. Ongoing dispersal can join numerous subpopulations to form a _______
A group of distinct, partially isolated subpopulations in widely separated discrete patches of breeding habitat within a matrix of unsuitable habitats that are linked only by dispersal / migration;
independent, local, habitat fragmentation, conservation of species
in metapopulation, each subpopulation has its own dynamics (_________);____ extinctions; re-colonizations; rescue effect; highly applicable to problems of __________ and ______________
3. A _____________ summarizes the pattern of survival in a population.
Patterns of _______ vary from one species to another; dictated by environment
3 Types (I, II, and III)
type of survivorship curves
Humans and most primates have a ______ survivorship curve.
In a ____ curve, organisms tend not to die when they are young or middle-aged but, instead, die when they become elderly.
Species with ______ curves usually have small numbers of offspring and provide lots of parental care to make sure those offspring survive.
Many bird species have a ______ survivorship curve.
In a ______ curve, organisms die more or less equally at each age interval.
Organisms with this type of survivorship curve may also have relatively few offspring and provide significant parental care.
Trees, marine invertebrates, and most fish have a ______ survivorship curve.
In a ______ curve, very few organisms survive their younger years.
However, the lucky ones that make it through youth are likely to have pretty long lives after that. Species with this type of curve usually have lots of offspring at once—such as a tree releasing thousands of seeds—but don't provide much care for the offspring
(1) Age distribution/population profiles, (2) Cohort life tables, (3) Static life tables
Recorded as part of life tables; can be estimated by (3)
4. The ________ of a population reflects its history of survival, reproduction, and potential for future growth.
proportion of individuals belonging to each age group
Gives an echo of past events influencing the population
May predict future outcomes
(1)Expanding, (2)Stable, (3) Declining
3 types of age distribution
An age-sex pyramid
is a "snapshot" of a population in time showing how its members are distributed among age and sex categories.
proportion of males to females
net reproductive rate (R0), geometric rate of increase (λ), generation time (T), and per capita rate of increase (r)
5. A life table combined with a fecundity schedule can be used to estimate
summarize birth and death rates for organisms at different stages of their lives.
an organism's potential for reproduction; measured by the number of gametes, seed set, propagules
the tabulation of birth rates for females of different ages in a population
Cohort life table
dynamic life table
a group of individuals born at the same time or over a short period
Cohort life table
Used to determine age- or stage-specific fecundity and mortality rates, survivorship, and basic reproductive rates, enables an analysis of their annual variation.
Static life table
contains the age groups in a population at one particular period of time.
Cohorts are not followed in time reconstructed using ___________ ______.
The assumption is that the mortality experienced by the cohort at any age ____ ______ in time
is the average number of offspring each individual leaves.
A value greater than 1
A value ________indicates a growing population.
is the average time from one generation to the next (e.g. from egg to egg or seed to seed of the next generation).
A negative r value
would indicate a declining population,
a positive r
indicates a growing population,
indicates a stable population.
can be used as a sensitive indicator of the ecological effects of environmental change.
THIS SET IS OFTEN IN FOLDERS WITH...
BIO 150 lecture 2
BIO 150 lecture 3
BIO 150 Lecture 8
BIO 150 lecture 10
YOU MIGHT ALSO LIKE...
Chapter 9 Population Growth
Chapter 10 Population Dynamics Ecology
OTHER SETS BY THIS CREATOR
people of genetics