Community ecology ii species interactions
This presentation is the property of its rightful owner.
Sponsored Links
1 / 33

Community Ecology II: Species Interactions PowerPoint PPT Presentation


  • 91 Views
  • Uploaded on
  • Presentation posted in: General

Community Ecology II: Species Interactions. Ecological communities: Assemblages of two or more species living and interacting in the same area. Species interactions : the ways different organisms affect each other and how they have adapted to each other’s presence.

Download Presentation

Community Ecology II: Species Interactions

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Community ecology ii species interactions

Community Ecology II: Species Interactions


Community ecology ii species interactions

Ecological communities: Assemblages of two

or more species living and interacting in the same area.

Species interactions: the ways different organisms

affect each other and how they have adapted to each other’s presence.


Community ecology ii species interactions

FOUR main kinds of species interactions; all play

a role in the formation of community structure...

Competition (-,-)

Predation, parasitism (+,-)

Mutualism (+,+)

Commensalism (+,0)


Community ecology ii species interactions

Interspecific Competition:

Use or defense of a resource by one species

that reduces availability of that resource

to a different species.

exploitative competition

interference competition


Competition in paramecium

Competition in Paramecium


Community ecology ii species interactions

Competitive Exclusion:

A result of competition between species

for a limiting resource, in which one

species completely eliminates the other.


Community ecology ii species interactions

Ecological Niche:

  • a species’ ecological ‘role’

  • all the environmental factors that influence

  • the growth, survival, and reproduction of a species

  • an n-dimensional hypervolume within which

  • a species’ population growth is positive


Community ecology ii species interactions

3-dimensional niche


Community ecology ii species interactions

Fundamental Niche vs Realized Niche

Fundamental Niche: the niche that a species potentially

could occupy, in the absence of competitors.

Realized Niche: the niche to which a species is restricted

in the presence of competitors.


Competition in barnacles

Competition in Barnacles


Community ecology ii species interactions

EXPERIMENT

RESULTS

Ecologist Joseph Connell studied two barnacle species—Balanus balanoides and Chthamalus stellatus —that have a stratified distribution on rocks along the coast of Scotland.

When Connell removed Balanus from the lower strata, the Chthamalus population spread into that area.

This suggests that Balanus is the superior competitor, preventing Chthamalus from occupying the low tide zone.


Community ecology ii species interactions

When Balanus are removed from the intertidal zone, Chthamalus expands to occupy the space formerly occupied by Balanus. What would you predict if one removed Chthamalus?

A) Since Balanus is the superior competitor, it probably would move up into the space Chthamalus occupied.

B) Since Chthamalus is the superior competitor, it probably would move down into the space Balanus occupied.

C) Since Balanus is the superior competitor, it probably cannot live in the high intertidal zone.

D) Balanus would disappear as well, since it preys on Chthamalus.

E) Because of the mutualistic association, the range of Balanus would shrink.


Community ecology ii species interactions

Competitive Release:

Expansion of a species’ ecological

niche when a competitor is removed

(usually in a removalexperiment).


Community ecology ii species interactions

Q: How do similar species coexist?

A1: Resource Partitioning


Community ecology ii species interactions

Resource Partitioning

  • Species using similar resources can coexist when the habitat is spatially and temporally complex, thus allowing for niche specialization


Community ecology ii species interactions

Anolis spp.


Community ecology ii species interactions

Number of different Anole species on different islands


Community ecology ii species interactions

FOUR main kinds of species interactions; all play

a role in the formation of community structure...

Competition (-,-)

Predation, parasitism (+,-)

Mutualism (+,+)

Commensalism (+,0)


True predators prey is killed immediately upon successful attack

True Predators - prey is killed immediately upon successful attack

Great White Shark, Siberian Tiger,

…Fox Squirrel?


Community ecology ii species interactions

Partial Predators- prey usually not killed but many prey organisms affected during predators lifetime - grazers, browsers

Giraffe, Bison, Monarch Caterpillar


Community ecology ii species interactions

Predators can influence species withincommunities by selecting for anti-predator adaptations in prey…


Behavioral defenses

Behavioral Defenses


Morphological defenses

Morphological Defenses


Community ecology ii species interactions

Morphological Defenses

Cryptic coloration

Flexible crypsis


Aposematic or warning coloration

Morphological & Physiological Defenses

Aposematic or Warning Coloration

Monarch Butterfly and Caterpillar


Blue jay eats monarch but vomits due to cardiac glycoside from milkweed

Blue jay eats monarch, but vomitsdue to cardiac glycoside from milkweed


E g wolves and moose on isle royale

Predators can also influence the abundance

and distribution of their prey.

e.g. Wolves and Moose on Isle Royale


  • Login