How many species are at risk of extinction?
15
Recovery
o
The
recovery time of a forest is nearly
40 years
, whereas the recovery of a marine area is
only about 10 years.
o
Disturbances such as agriculture can take 50 years to recover, logging can take 30 years
to recover, and deforestation can also take up to 30 years to be recovered.
Why we should preserve biodiversity
1.
New
medicines
from untested species
25% of all drugs come from nature.
Nature is our free pharmacy!
A biodiversity treaty stated that developing nations should receive royalties from the
plants we sell for medicine, but the US didn’t sign it. We should pay for them so that the
developing nations can preserve them!
2.
Improved
ecosystem function
Ecosystems are our human life support and is based on biodiversity.
3.
Food
from new species
Only 30 species currently provide 90% of the food that we eat, but there are 1 million
described plant species!
There are 600 species of dogs, but only 50 species of beans. We can obviously create
more variety!
ECOL 1000
Lecture #8
February 4, 2016
Green Revolution: creating
new types of crops with high nutrient quality
Modern crops
are bred for fast growth, short stalks, and large number of kernels per ear/stalk.
They require a lot
more energy to grow than wild crops!
Wild varieties
of crops are
disease, drought, and pest resistant
Why we preserve biodiversity
Besides for
medicine
, ecosystem
services
, and
food
, more reasons include
Preservation of
genetic diversity
o
Doomsday vault preserves seeds in long term storage for future use in case the earth is
destroyed.
16
o
Humans have begun a “clean-freak” culture where we are out to destroy microbes.
These
