Ecosystem Diversity
1. What is biodiversity?
2. Where did all these species come
from?
3. Can new species form?
4. How do humans effect biodiversity?
5. How do we prevent extinction?
6. Why is it important to have so many
different species? (in other words,
what roles do they play in an
ecosystem?
Tuesday
1. What is biodiversity? (p 78-80)
2. Where did all these species come from?(p 80-83)
3. Can new species form?(p 86-87)
What is biodiversity?
• Biodiversity is the variety of the earth’s species, the
genes they contain, the ecosystems in which they live
and the ecosystem processes such as energy flow that
sustain all life.
• Its super important, really its vital.
• Just for grins: ID: 1.8 million but think there is 4100million out there.
• How we look at biodiversity
–
–
–
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Species diversity
Ecosystem diversity
Functional diversity
Genetic diversity (allows to adapt)
Where did all these species come
from?
• Biological Evolution: change over time. (in
populations not individuals)
• Darwin’s theory:
– Common ancestor
– Natural selection: most fit organism survives to
reproduce.
– Allows organisms to adapt to their environment.
– What causes the changes in individuals = mutations
Mutation= individuals are selected=populations evolve
that are better adapted to the changing environment.
Can new species form?
• Speciation: forming of a new species.
• Mechanisms for speciation: reproductive
isolation or geographic isolation.
Wednesday
1. How do humans effect biodiversity? (pg. 8789)
2. How do we prevent extinction?
3. Why is it important to have so many different
species? (in other words, what roles do they
play in an ecosystem?
What are the effects humans cause in
a species?
1. Extinction vs. Endemic
-mass extinction: amphibians?
2. Invasive species
How do we prevent extinction?
1. Conservation (protected areas)
2. Insure species diversity:
(species richness vs species evenness).
species richness: lots of different
organisms
species evenness: relative abundance of
each species.
Species richness = sustainability
Roles
• Ecological niche: the role of a species
• Generalist: can live in many different places and eat many
different foods? (raccoons, deer, beetles, rats, mice)
• Specialist: occupy a narrow niche (panda, tiger
salamanders)
• Native species vs. invasive (nonnative, alien, exotic)
• Indicator species: species that provide early warning signs.
• Keystone species: have a larger effect on an ecosystem than
their numbers would suggest. (alligator or prairie dogs)
• Foundation species or ecological engineers: plays a major
role in shaping communitites by creating and enhancing
their habitats.
Now that we have looked back over
our notes…
• Speciation: Of Ligers & Men - Crash Course
Biology #15 – YouTube
• Words you may want to add that are not in your
book. ( I don’t have to tell you your book is not
the best)
• Allopatric speciation
• Sympatric speciation
Lets get ready for POPULATION
ECOLOGY!!!
Population Ecology
Characteristics
Factors
Growth Models
Estimating Populations
Measuring Diversity