DISPERBAL AND...

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DISPERSAL AND COLONIZATION ANI MARDIASTUTI

Transcript of DISPERBAL AND...

DISPERSAL

AND

COLONIZATION

ANI MARDIASTUTI

Process whereby an organism is able to

spread from its plate of original to

another locality

Dispersal

Dispersal → hinders by

environmental factors → barriers

Barriers

Physical Barriers ☻ Water

☻ Topography (Mountain, Cliffs, valley)

☻ Desert

Ecological Barriers ☻ Climate zones

☻ Living environment

☻ Cultural desert

☻ Ecological “desert” (Salinity, Soil type, etc)

Dispersal

Active

(by the organism)

Passive

(by a carrier)

Active Dispersal

Plants → seeds, spores

Animal → organs and modes of

locomotion

Passive Dispersal

Anemochore dispersal

(wind and air current)

Hydrochore dispersal (water)

Anemohydrochore dispersal

Biochore dispersal (other organism)

Anthropochore dispersal (by human)

Anemochore Dispersal

Airborne

By air

Hydrochore Dispersal

Rafting Eaten by birds

Anemohydrochore Dispersal

Biochore Dispersal

Burung laut

Burung merpati

Anthropochore

Dispersal Unintention

Anthropochore Dispersal by Intention

Dispersal Route

Dispersal

Route

Sweepstaker

Dispersal Route Lard Bridge

A process of setting down by an organism in

a new habitat

Colonization

Good Colonizers

Able to with stand extreme

condition (? Of food and water)

Good ability to reproduce good

Good competitor, if necessary

“pioneer” species

Dispersal

Colonization

Existence

Colonization of Krakatau (Erupted in 1883)

Colonization of Krakatau (40 years)

Colonization of Krakatau (100 years)

DISPERSAL AND COLONIZATION

1. Start with

one continuous

population.

Then, a colonist

floats to an

island on a raft.

2. Finish with

two populations

isolated from

one another.

Island

Continent

Why would these

populations

diverge into

separate

populations?

DISPERSAL AND COLONIZATION

1. Start with

one continuous

population.

Then, a colonist

floats to an

island on a raft.

2. Finish with

two populations

isolated from

one another.

Island

Continent

- genetic drift -

colonists are few and

likely to be non-

random sample of

original population

- natural selection -

selection pressures in

new environment are

unlikely to be the

same as in old

environment

- leads to different

species on islands vs.

mainland