Section 3.3. Describe (at least) 3 things that make up an organism’s niche: Habitat What/when it eats What eats it How it reproduces How much

Community Interactions

Section 3.3


Describe (at least) 3 things that make up an organism’s niche: Habitat What/when it eats What eats it How it reproduces How much water it needs


Explain how an organism’s niche is slightly different than its habitat: The niche is more than just where the

organism lives, it also includes what it does.

Organisms may share the same habitat, but never the same niches.


Examine fig. 1 on page 68, then explain how the lynx and the wolf are able to share the same habitat without too much competition.


Examine fig. 1 on page 68, then explain how the lynx and the wolf are able to share the same habitat without too much competition. Each has different behaviours or traits

that allow them to exploit different parts of the niche: different timing, different hunting strategies.


Explain what happens when two species are forced to occupy the same niche rather than the same habitat.

COMPETITION will occur!


Define competition: Competition occurs when species make

use of the same resource so that their niches conflict or overlap with each other.


Explain the difference between interspecific competition and intraspecific competition. Interspecific competition:▪Competition between different species.


Explain the difference between interspecific competition and intraspecific competition. Intraspecific competition:▪Competitionbetweenmembers ofthe samespecies.


Explain how the hawk and the owl have adapted traits that have allowed them to adapt to competition between them.


Explain how the hawk and the owl have adapted traits that have allowed them to adapt to competition between them. The hawk works on the day-shift

(diurnal). The owl works on the night-shift

(nocturnal). This way, even though their niches are

similar, they don’t overlap so that they can coexist


Define adaptive radiation: Adaptive radiation occurs when species

adapt differently to changes in the environment.

Species becomespecialized inorder to exploitsmaller ordifferent parts ofa habitat.


How did the finches on the Galapagos Islands undergo adaptive radiation in order to reduce competition among themselves? Over time, the finches adapted different

beak sizes and shapes in order to exploit the different food sources available to them.


Adaptive Radiation


Define proliferation: Proliferation occurs when organisms

with these adapted traits increase in numbers due to natural selection.

The Impact of Foreign Species Define a foreign species:

Species that are introduced into an area that they are normally not native to.

So why do these foreign species often pose a real danger to native species? 1. Sometimes they out-compete native

species for a niche. 2. They rarely have any natural predators

in the new habitat.

The Impact of Foreign Species

Give one example where the introduction of a foreign species is beneficial.


Give one example where the introduction of a foreign species is beneficial. The introduction of food crops like corn,

wheat, and fruit trees.


Give one example of a foreign plant species that was introduced into BC that proved to be harmful to the ecosystem.


Give one example of a foreign plant species that was introduced into BC that proved to be harmful to the ecosystem. Eurasian milfoil or Scotchbroom.


Give two examples of foreign animal species that were either intentionally or unintentionally introduced to BC.


Give two examples of foreign animal species that were either intentionally or unintentionally introduced to BC. European starling and Pacific Oyster

Succession

The word succession means “to take place of”.

Define ecological succession: The gradual change in the type of plants

in a community.

Succession

Suppose a logging company has clear-cut a section of the forest for its timber, but never replanted the trees that it cut down.

Over time, if thearea was ignored, ecologicalsuccession wouldoccur.

Succession

What is the name of the first step in ecological succession?

Succession

What is the name of the first step in ecological succession? Pioneer species.

Give an example of an organism that very often begins primary succession and what they are called.

Succession

Lichen or mosses often appear first because they can grow during conditions of no soil or nutrients and begin by breaking down rock and trapping windblown particles and producing soil.

They are called pioneer plants.

http://danny.oz.au/travel/iceland/p/3056c-pioneer-plant.jpg

Succession

In the end, if there is sufficient rainfall, nutrients and sunlight, the community will develop into a stable ecosystem called a climax community.

Succession

Succession

Define secondary succession: Secondary succession occurs when

there is already decent soil in the area, but something like a fire or clear-cut logging has removed the natural vegetation.

Seeds that are in the soil, or brought by the wind/birds now become the pioneer species eventually becoming a climax community.

Assignment

CYU 3.3 page 73: 1, 3, 4, 5, 6, (full sentences) 7, 8, ( multiple choice) 9, 11, (full sentences)

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Section 3.3. Describe (at least) 3 things that make up an organism’s niche: Habitat What/when it eats What eats it How it reproduces How much