Download Ecology

Biodiversity
Day 6
What is Biodiversity?
The variety of life in an area that is
determined by the number of different
species in that area.
• There are 2 main types:
Number of
different species in
a community
1) Genetic Diversity
The variety of genes in a
population
2) Species Diversity
Why is biodiversity important?
1)Direct
economic
value
Penicillin: Derived from
bread mold
Teosinte: A
distant relative
of corn w/
resistance to
viral diseases
Domestic corn
plant
2)Indirect
value – ex.
treatment of
diseases
Madagascar Periwinkle: Used to
treat childhood forms of leukemia
Extinction Rates
• The gradual process of becoming extinct is
known as background extinction.
• Mass extinctions: When a large percentage of
all living species become extinct in a relatively
short period of time.
• 250 MYA: Over
90% of species
died
Estimated number of Extinctions since
1600
Group
Mainland
Island
Ocean
Total
Approximate
Number of
Species
Percent of
Group
Extinct
Mammals
30
51
4
85
4000
2.1
Birds
21
92
0
113
9000
1.3
Reptiles
1
20
0
21
6300
0.3
Amphibians
2
0
0
2
4200
0.05
Fish
22
1
0
23
19,100
0.1
Invertebrates
49
48
1
98
1,000,000+
0.01
Flowering
Plants
245
139
0
384
250,000
0.2
Five Most Recent Mass Extinctions
Cretaceous Period (65 MYA)
Triassic Period (200 MYA)
Permian Period (250 MYA)
Devonian Period (360 MYA)
Ordovician Period (444 MYA)
Activity: Understanding Geological
Time
• Working in your groups, you will get the
following supplies:
– A meter stick
– A roll of 5 meters of paper
– Colored pencils
• Using the worksheet, plot out the dates.
– 1 million years is a millimeter
– 1 billion years is a meter