Transcript Biodiversity

Biodiversity
Unit 3
Environmental Science 1
What is diversity?
Diverse: differing from
one another;
composed of distinct
or unlike elements or
qualities
Diversity: the condition
of being diverse
Biodiversity: Biological
diversity in an
environment indicated
by number of different
species of plants and
animals
Why is there diversity?
Charles Darwin
came up with the concept
of “Law of Natural
Selection” – meaning only
the fittest survive
If only the fittest survive –
why so much diversity?
Over time organisms
develop a niche in the
environment – they serve a
purpose and in turn the
environment needs that
organism to function
Why is there diversity?
If only the strong survive, why are
there so many organisms?
Three reasons:
1. Because of niches
2. Geological separation
3. Environmental factors
Why is there diversity?
Niches:
Niches are jobs or roles
an organism has in a
particular ecosystem
If two organisms are
competing for the same
niche the weaker
organism will “lose” –
this is simply called
competition
An exotic or invasive
species has no
competition or
predators and can
overtake and/or destroy
an ecosystem
Why is there diversity?
Geologic
separation
For example, the same
species may be separated
by migration, plate
tectonics, etc and adapt to
a new environment and as
a result a new species
forms
Environmental
reasons
The warmer and wetter
the climate the more
diversity it can hold
because there is less
fluctuation in conditions
The Importance of Diversity
Biodiversity is
important to human
survival
For example, was seen
in the potato famine of
the 1840’s – only a few
species of potatoes
were planted and when
a fungus killed off the
potatoes 2 million
people died of hunger
and disease
Importance of Diversity
Reasons for
preserving
biodiversity
All life has a right to
exist
Variety adds enjoyment
to life
Diversity brings stability
to our biosphere
Diversity has economic
and medical value
Modern agriculture is
tied to biodiversity
What effects biodiversity?
Competition is
when two
organisms are
competing for
similar resources –
they both fill the
same niche
When two
organisms are in
the same niche
resources become
scarce one or both
organisms become
effected
What effects biodiversity?
Adaptation effects
biodiversity by
increasing it – an
organism that is
adapted to a variety of
environment is less
limited in where it can
live – that is one of the
reasons why there are
so many humans on
the planet
How to Preserve Diversity
Set aside large areas
of land to preserve the
wilderness in the form
of parks, monuments
and wildlife refuges
Collect, preserve and
maintain a variety of
seeds from different
areas
Use genetic
engineering to change
genetic information at
the molecular level
Endangered Species
Extinct: the last remaining
member of the species has
died, or is presumed
beyond reasonable doubt
to have died
Examples: Thylacine,
Dodo, Passenger
Pigeon
Extinct in the wild:
captive individuals survive,
but there is no free-living,
natural population
Examples: South
China Tiger, Alagoas
Curassow
Endangered Species
Critically endangered:
faces an extremely high
risk of extinction in the
immediate future
Examples: Arakan
Forest Turtle, Javan
Rhino, Brazilian
Merganser
Endangered: faces a very
high risk of extinction in the
near future
Examples: Blue
Whale, Snow Leopard,
African Wild Dog, Tiger,
Albatross, Crowned
Solitary Eagle
Endangered Species
Vulnerable: faces a
high risk of extinction
in the medium-term
Examples: Cheetah,
Gaur, Lion, Wolverine
Conservation
Dependent: The
following animal is not
severely threatened,
but the animal must
depend on
Examples: Spotted
Hyena, Leopard Shark,
Black Caiman
Endangered Species
Near Threatened:
may be considered
threatened in the near
future
Examples: Blue-billed
Duck, Solitary Eagle,
Small-clawed Otter ,
Maned Wolf
Least Concern: no
immediate threat to
the survival of the
species
Examples: Brown Rat,
Nootka Cypress, Wood
Pigeon