Transcript 1.3 and 1.4 - WordPress.com

Classifying Animals
- PROKARYOTE vs EUKARYOTE
- UNICELLULAR vs MULTICELLULAR
- Dichotomous Keys
What is biodiversity?
• 3 levels of biodiversity are...
• Genetic, Species, Ecosystem
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Level 1: Genetic Diversity
The genetic differences among species are attributed
to species having different alleles of the same gene.
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Genetic Diversity
• Why is it important?
• Gene pool: the sum of all the versions
of all the genes (alleles) in a
population
• How do you define a population?
 Same species, area and time.
• Would there be a greater genetic
diversity within a species or a pop’n?
Within a species.
White-cheeked Rosella,
showing genetic variation that
is geographically based
Within a population.
Spring Beauty, where different
genetic strains are found in the
same forest.
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Homo sapiens, where
genetic diversity has a
geographic pattern, but
which shows much
diversity within local
populations too.
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Distribution of O blood type in South America
The O allele is almost fixed whereas A is rare and B is absent)
Level 2: Species Diversity
Beetles: Over 350,000 species on Earth
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Species Diversity
• The variety and abundance of species
in a given area.
– E.g. populations, subspecies, “races”
• Species diversity helps conservationists
decide where to concentrate efforst
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Species Diversity is all around us…
• “Researcher Finds New Bee Species in
Downtown Toronto” (2010)
• A York University Ph.D. student, who
discovered a new species of bee on his way to
the lab one morning, has completed a study
that examines 84 species
of sweat bees in Canada…
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Level 3: Ecosystem Diversity
Ecosystems are hard to
characterize since (a)
boundaries are often “soft”,
and (b) no two landscapes
are really the same.
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Ecosystem Diversity
• The variety of ecosystems in the
biosphere.
• Ecosystems provide “ecosystem services”
– Each a different organ in the body of earth
– Pg. 37 #9
• They are resilient
• Why is it bad for humans to alter
ecosystems to enhance its “services”?
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Ecosystem Diversity
• Which of the following are ecosystems?
a)
b)
c)
d)
e)
Flower basket
Surface of your skin
Schoolyard
Lake Ontario
The tundra
• What do your answers tell you about
ecosystem diversity?
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Homework
• Create a dichotomous key for Kingdoms
– Use Table 1.5 on page 29 as a guide