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.

 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: ▪ Competition between members of the same species.

 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 become specialized in order to exploit smaller or different parts of a 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.

 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.

 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.

 Eurasian milfoil or Scotchbroom.

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

 European starling and Pacific Oyster

 The word succession means “to take place of”.  Define ecological succession:  The gradual change in the type of plants in a community.

 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 the area was ignored, ecological succession would occur.

 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.

 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.

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

 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.

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