Ecology Flashcards
Populations are groups of individuals in one _______ and _______
place, time
A _______ _______ is the area throughout which a population occurs
Geographic Range
A _______ is the biotic and abiotic feature of a population’s range
habitat
Population _______ is how individuals are physically spaced out
density
Population _______ is the number of individuals and how that number changes through time
size
Ranges of populations change through time with _______ changes
environmental
Individuals in populations exhibit different _______ patterns (how they interact with each other)
spacing
_______ _______ : Individuals do not interact strongly with one another (not common in nature)
Random spacing
_______ _______: Behavioral interactions, resource competition
Uniform spacing
_______ _______: Uneven distribution of resources (common in nature)
Clumped spacing
_______ occur in areas in which suitable habitat is patchily distributed and is separated by intervening stretches of unsuitable habitat
Metapopulations
In dispersal: interaction may not be _______; Populations ________ and send out many dispersers; _______ populations have few dispersers; Individual populations may become _______; Population _______ may occur
symmetrical, increase, small, extinct, bottlenecks
In _______-_______ metapopulations, some areas are suitable for long-term habitat while others are not.
Source-sink
In source-sink metapopulations, populations in better areas (_______) bolster the population in poorer areas (_______)
source, sink
In source sink metapopulations, the species occupies a _______ area than is otherwise might. Also, the continuous colonization of empty patches prevents _______-_______ _______
larger, long-term extinction
_______ is the quantitative study of populations
Demography
Demography measures how _______ changes through time
size
Population growth can be influenced by the population’s _______ _______
sex ratio
Populations with _______ generations can increase in size more quickly than populations with _______ generations
short, long
_______ _______ is determined by the number of individuals in a different age group
age structure
_______: Group of individuals of the same age
Cohort
_______: Number of offspring produced in a standard time
Fecundity
_______: Death rate in a standard time
Mortality
_______ is the percent of an original population that survives to a given age
Survivorship
Natural selection favors traits that maximize the number of _______ _______ left in the next generation by an individual organism. 2 factors affect this quantity: _______ and how many offspring it produces each year
surviving offspring, lifespan
_______ offspring have a greater chance of survival
Larger
_______-_______ species delay reproduction. The advantage is that juveniles gain experience before the high cost of reproduction
Long-lived
_______-_______ species reproduce early. Time is important; delay may mean no offspring
Short-lived
_______ _______ model applies to populations with no growth limits
Exponential growth
Exponential growth equation: _______
r = (b-d) + (i-e) where r = rate of population increase; b = birth rate; d = death rate; i = immigration; e = emigration
_______ _______: e = i, and there are no limits on population growth, then: dN/dt = riN. N is the _______ of individuals in the population; dN/dt is the rate of change over time; ri is the _______ rate of natural increase for the population
Biotic potential, number, intrinsic
The biotic potential of any population is _______ , even when the rate of increase remains constant.
exponential
The result of unchecked exponential population growth is _______ _______
population explosion
_______ _______: Symbolized by K, is the maximum number of individuals that the environment can support
Carrying capacity
_______ _______ _______: Applies to populations as they reach K (carrying capacity, the max number of individuals the environment can support)
Logistic growth model
Logistic Growth Model: _______
dN / dt = rN (K - N) / K
As N approaches K, the rate of population growth begins to _______
slow
If N = K, the population growth rate is _______
zero
If the population size exceeds K, the population size will _______ until it reaches K
decline
_______-_______ factors affect the population and depend on population size
Density-dependent
_______-_______ factors, such as natural disasters, affect populations regardless of size
Density-independent
_______ _______ _______ of a population at any instant is limited by something unrelated to the size of the population, such as external _______ aspects
Rate of growth, environmental
_______ availability affects life history adaptations.
Resource
_______-_______ populations are adapted to thrive when population is near its carrying capacity
K-selected
When resources are limited, the cost of _______ is high
reproduction
_______-_______ populations are populations far below their carrying capacity, where resources are abundant
r-selected
In r-selected populations, costs of reproduction are _______
low
In r-selected populations, selection favors individuals with the highest _______ rates
reproductive
Most natural populations show live history adaptations that exist along a continuum of _______- and _______- selected traits
r, K
Some K-selected life history traits include: Small _______ size, late _______, and a high degree of _______ _______
offspring (brood), reproduction, parental care
_______-_______ species are adapted to function well in rapidly changing environments
r-selected
In r-selected species, the organisms are generally _______, have _______ generation times, and produce many offspring in a single reproductive event. They usually receive little or no _______ _______.
small, short, parental care
r-selected species have a high _______ - populations grow exponentially when conditions are favorable. Also, most offspring die before reaching _______ maturity (Type ___ survivorship)
r max, sexual, III
In K-selected species, the organisms are generally _______, have _______ generation times, and produce little offspring (high quality) in a single reproductive event. They usually receive substantial _______ _______.
large, long, parental care
r-selected species have a low _______ - populations grow slowly. They have Type ___ or ___ survivorship)
r max, I, II
A biological _______ are species that occurs at any particular locality
community
Biological communities are characterized by species _______ (the number of species present) and primary _______ (the amount of energy produced)
richness, productivity
_______: Places where the environment changes abruptly
Ecotones
_______: The total of all the ways an organism uses the resources of its environment
Niche
Examples of niches are: _______ utilization, _______ consumption, _______ range, _______ conditions, etc.
Space, food, temperature, mating
_______ competition occurs when two species attempt to use the same resource and there is not enough resource to satisfy both
Interspecific
_______ competition is when there are physical interactions over access to resources
Interference
_______ competition is when the same resources are consumed
Exploitative
A _______ niche is an entire niche that a species is capable of using, based on physiological tolerance limits and resource needs
fundamental
A _______ niche is the actual set of environmental conditions, presence or absence of other species, in which the species can establish a stable population
realized
_______ _______: If two species are competing for a limited resource, the species that uses the resource more efficiently will eventually eliminate the other locally
Competitive exclusion
_______ _______ is often seen in similar species that occupy the same geographic area, where they divide limited resources
Resource partitioning
_______ _______ is differences in morphology evident between sympatric species
Character displacement
_______ is the consuming of one organism by another
predation
Plants adapt to predation (_______) by evolving mechanisms to defend themselves. They evolve _______ defenses (secondary compounds) like oils or poison
herbivory, chemical
Herbivores _______ to continue eating plants despite defense mechanisms
coevolve
Insects and other animals that are poisonous use _______ coloration.
warning
Organisms that lack specific chemical defenses use _______ coloration to help them blend with surroundings.
cryptic
Camouflaged animals do not usually live in _______
groups
_______ allows one species to capitalize on defensive strategies of another
mimicry
_______ mimicry is where mimics look like a distasteful species
Batesian
_______ mimicry is where several unrelated but poisonous species come to resemble one another
Mullerian
_______ is where 2 or more kinds of organisms interact in more-or-less permanent relationships
Symbiosis
_______ benefits both species. They may coevolve
Mutualism
_______ benefits one species at the expense of another
Parisitism
_______ benefits one species and is neutral to the other
Commensalism
_______ species are species whose effects on the composition of communities are greater than one might expect (like beavers)
Keystone
_______: Communities have a tendency to change from simple to complex
Succession
_______: Early successional species are characterized by _______-_______ species tolerant of harsh conditions
Establishment, r-selected
_______: Early successional species introduce loyal changes in the habitat. _______-_______ species replace r-selected species.
Facilitation, K-selected
_______: Changes in the habitat caused by one species inhibits the growth of the original species
Inhibition
Communities are constantly changing as a result of: _______ changes, _______ invasions, _______ events
Climatic, species, disturbance
_______ is common, rather than exceptional in many communities
Disturbance
