Chapter 3 slides

Community Ecology

1

Adaptation = genetic trait that improves an

organism’s chance at survival and

reproduction

Not a real

adaptation

2

Two butterfly species – one tastes bad and the

other doesn’t (but looks like it does)

3

Darwin’s Galapagos Island Finches

4

If females prefer large elaborate tails, then

those are the males that pass their genes on

get bigger and more elaborate with each

generation

5

6

Species that are best adapted to their

environment have a better chance at survival

and reproduction

“environment” includes habitat, climate,

presence of predators or competitors,

availability of resources, natural disasters

These factors can change

Species that do not adapt do not survive

DIVERSITY is required for adaptation!

7

Peppered moth

example

It’s important

to remember

that no moth

changed its

colour

The number of moths of each colour changed

8

Niche = an organisms role in an ecosystem

Examples: top predator, pollinator, decomposer,

mussel consumer, cave dweller, etc.

If two species occupy the same niche AND

resources are limited COMPETITION

Limits the size and health of an individual

and/or population

9

Luongo’s niche? Goalie

His competition? Schneider (same niche)

If Luongo’s playing well, Luongo plays more. If Schneider doesn’t perform well, Luongo plays more.

How well the

Sedins play has

no effect on how

much ice time

Luongo gets

(DIFFERENT NICHE)

10

What effect would each of the following have on the competition level for Luongo?

If the canucks were allowed 5 backup goalies competition would increase (more individuals

occupying same niche)

If the canucks were allowed to play two goalies at once competition would decrease (more resources = less

competition)

If the canucks were only allowed to dress one goalie instead of two competition would increase (fewer resources = more

competition)

11

Foreign species (Introduced species) =

species that are not native to an ecosystem

Invasive species = species which harms its

new ecosystem

How? It out-competes native species

Have an advantage because they have no

predators/consumers

Humans cause introduction of species to new

ecosystems worldwide

12

Process by which plants in an ecosystem

change gradually over time

13

PRIMARY – ecosystem begins as bare rock (no soil)

First settlers (pioneer species) create soil

Eventually climax community including all types/sizes of plants and consumers

SECONDARY – same as primary but soil is already present

Occurs after events such as forest fires

14

Pioneer species

growing in lava rock