the sixth extinction? topic 7 pg. 66-72. did you know.... in the last 600 million years, there have...
TRANSCRIPT
The Sixth Extinction?
Topic 7
Pg. 66-72
DID YOU KNOW....
In the last 600 million years, there have been 5 major declines in Earth’s Biodiversity!
In the last 65 million years, the rate at which new species were formed has been greater than the rate of extinction
Today, the rate of extinction may be 70 extinctions per day!
Which type of species is most diverse?
As the rate of extinction increases, the scales are tipped toward an overall trend of decreasing biodiversity.
EXTINCTION
NEWSPECIES
How have humans affected Biodiversity?
http://www.youtube.com/watch?v=csqJ_ULmQL8 Human Impact (Call of Life) 9 min
Human Impacts Some areas of the world
support greater biological diversity than others
What promotes the growth of plants, which leads to more complex food chains and greater biodiversity?
Disapprearing Habitats A grizzly bear is an example of a
bioindicator species. What does that mean?
Species that help indicate environmental change
Usually one of the first effects of human interference in an ecosystem is loss of large carnivores such as bears and wolves
Where Have all the Grizzlies Gone? Pg. 68 Read “Think About it” Define extirpation Work with a partner to study the
map and brainstorm possible reasons to explain why grizzly bear populations have decreased
Analyze: #1-4 (work with partner)
The population explosion Developing nations are often
hardest hit by population explosion
Areas of tropical rain forests are often cleared to make small farms Extinction of particular species Loss of food and protection Lack of nutrients in soil
Prevents regrowth in forests
Pains and GainsTopic 8: pg. 73-78
How do we deal with the loss of biodiversity?
What do you think? Answer in your notes!
Protected Areas
Protected Areas are preserves, refuges and national parks set up to protect wildlife and habitat.
ZOOS Educational institution Protect and preserve
endangered animals Maintain genetic diversity of
particular species Supports research on
biodiversity around the world
Seedbanks Gather and store seeds from
plants that are threatened with extinction
Run by different people (governments, individuals)
Preserve genetic diversity
Global treaties
Local and global co-operation Protect endangered plants and
animals
Convention of International Trade of Endangered Species (CITES) Prevent import and export of
animals Leopards and cheetah skins
Rhinoceros and elephant tusks
Rare birds
Are there any problems or issues that you see in these diversity-conserving measures?
Answer in your notes!
To do:
Topics 6-8 Wrap Up, 1-7, 9, 10 Due for Monday
Topic 6-8 Quiz will be on Monday!