Lecture 9 + 10 Flashcards
Competition between individuals of the same species is which type of competition?
Intraspecific competition
A single algal species competes for a required resource, silicate. As the number of individuals increases, there is less silicate available for the original individuals. This is an example of:
Exploitation (competition)
Snowy plovers, a coastal bird species, are found to live only on sandy beaches. Where snowy plovers live is referred to as their:
Habitat
Competition between individuals of the same species can have effects on their
- survival
- growth
- reproduction
- access to mates
For any given species, there is a _______, which describes the niche that occurs under normal circumstances of interspecific competition within a community and typically differs from the hypothetical ______, which describes the niche that the species would inhabit if interspecific competition was removed.
realized niche, fundamental niche
The Competitive Exclusion Principle states that
If two competing species coexist in a stable environment, then they do so as a result of niche differentiation
Six types of species interactions
- amensalism
- commensalism
- competition
- exploitation
- mutualism
- neutralism
The six types of species interactions are based on how 2 species influence each other’s fitness
A negative, positive, or no effect on another species.
Example of exploitation
+/-
A spider eats a fly
Example of competition
-/-
A sparrow and a cardinal eat the same seeds
Example of mutualism
+/+
A butterfly and a flower
Example of neutralism
0/0
Two species that don’t influence each other
Example of commensalism
+/0
A vulture eats the scraps of a lion’s kill
Fungi on dead trees
Example of amensalism
-/0
A flower is stepped on by an elephant
Frog calls affecting an owl’s ability to hear prey/mice
Competition
Can be for any limited resource (ex. mates, locations, food, etc.)
It is a -/- interaction, it is not like sports
- there are costs to competition energetic expenditure, time, risk of injury, etc.
Pizza arrives at a party and those individuals who randomly smell and find the pizza first will get the pizza and some people will go hungry. What type of competition is this?
Intraspecific competition and exploitation competition
- however, not technically a species interaction
- not the same as an +/- exploitation interaction; this is a form of competition based on exploiting resources
At a pizza party, you drop your pizza but a cute dog prevents you from getting the pizza. What type of competition is this?
Interspecific competition
Interference competition
At a party, someone else flirts with your potential mate. What kind of competition is this?
Intraspecific competition
Interference competition
Intraspecific competition
Occurs among individuals of the same species
Interspecific competition
Occurs between individuals of different species
Exploitative competition (resource or scramble competition)
Competition between individuals by reducing availability of shared resources
Interference competition (contest competition)
Direct competition between individuals for scarce resources by one impeding or denying access to the resource by another
Competition
As population size increases intraspecific competition typically becomes greater.
This also applies to interspecific competition (the -/- interaction). If there are many individuals of a competitor species around, it can reduce fitness.
Competition over resources
Resource utilization curves
ex. small ground finches eat small seeds, medium eat medium seeds, large eat large seeds. Three different resource curves: seed depth (mm) x diet proportions