Competition Flashcards
Define two ways population abundance can increase in two ways it can decrease
Through immigration and birth or through emmigration and death
Define exponential growth
As a unit increases the rate of change increases, it is proportionate to the current value
Malthus Observed that human populations typically display logistic or exponential growth? Under what conditions is this known to be true
He observed that humans typically display exponential growth which can only happen if there are enough resources to do so, any species will grow exponentially if they have the opportunity to
As a population grows and approaches its K, does competition increase or decrease
It increases, K is the symbol for carrying capacity of the environment and represents the max number of individuals that can be supported in a given population. As the population grows near the max K competition increases because the availability of resources diminishes
What is the growth rate of a population at K? Growth rate at a point exceeding K
The growth rate at K is zero, if it exceeds K then the growth rate will be negative and the population abundance will drop until it is at K
Explain what gave rise to the four unique morphotypes of arctic charr in Iceland
Intense competition and becoming trapped in the lake with very low productivity and extremely low species diversity
Any mutations that allowed the species to exploit alternative resources would release the severe selection pressure
What did Elton mean by the term functional niche? What are the two main limitations of this sort of approach
He saw the niche as being a description of the ecological function of the species. Limitations are that it is difficult to quantify and therefore it cannot be analyzed or tested and it is too broad/ interactions may not be clear
Hutchinson Redefine this idea by coming up with the fundamental niche and realized niche define and contrast these two
Fundamental niche is the ideal niche that a species would have if there is no competition or predation
Realized niche is the niche that the species takes up based on the competition and limited resources of its ecosystem
Competition will increase or decrease as the area of niche overlap increase is between two species
It will increase because these two species will start to compete for this niche, nice overlap is a prerequisite for competition in the greater the overlap the greater the competition
If two species have extensive or even full niche overlap is there a competition between these two species
No not necessarily, the shared resource has to be limiting
Identify three ways to increase the number of species in a community
Increase range of resources
Increase degree of specialization
Increase the overlap tolerated between competitors
Fully saturate the available resources
As a community matures do we expect the fundamental niche of a species to grow our contract why
Contract because the community matures, more species colonize the area and as a result a species find itself in competition with more and more species. Therefore overtime it’s realized niche starts to contract
Give an example for each of the following types of competition mate, exploitative, preemptive, interference
Mate: to Bull Moose fighting over a cow
Exploitative: commercial fisherman harvesting salmon
Preemptive: A barnacle establishing a rock surface, no space for others
Interference: Any territorial species that restricts access to an area, lions
Define and give an example of a secondary sexual characteristics
Characteristics that males have to show the females that they have enough energy to create many children, show fitness to the females during meat competition
Pink salmon have humps on their back’s, red color, and long jaws
Are secondary sexual characteristics more common in females or males why
Males, This is used for males to compete with other males to show greater fitness two females (show their ability to harvest resources from the environment )
