Transcript The Silence of the Frogs

The Silence of the Frogs
 1. According to scientists about 30% of North
American frogs are in trouble.
 2. Based on scientific reseach it is believed that
amphibians have been on earth for over 400
million years.
3. Frogs were able to survive catastrophes that
other organisms were not because of their ability
to live on both land and water.
 4. An ecosystem is defined as the
relationship among many species living in
a specific area and the relationship
between the species and the non living
components of the environment.
 5. Scientists are concerned about the
decline because frogs provide information
about both land and water ecosystems.
Thus, the health of frogs may well indicate
the health of the 2 ecosystems they live in.
 6. Amphibian means “ 2 lives.”
 7. Frogs may in twice the danger of other
organisms because they live in both land and
water during their life.
 8. Malaria is a disease carried by mosquitoes.
The disease affects humans.
 9. The increase in malaria can be linked to
frogs as frogs eat mosquitoes. Less frogs
means more mosquitoes. More mosquitoes
means more malaria.
 10. A detritus food chain is one involving
decomposers. The decomposers return nutrients
back into the environment.
 11. There are 4 main reasons why frogs are
disappearing:
 a) loss of habitat – place where frogs live are being
used for industry, homes, farmland and highways.
 b) air and water quality – pollution has caused
several problems with frogs as pollutants easily pass
through a frogs skin. Acid rain has also affected the
development of eggs laid in water containing high
acid levels as it affects sperms ability to swim as well
as embryos often show deformities
 c) ultraviolet radiation – uv radiation causes skin
burns which has then been linked to cell
damaged.
 d) climate change – global warming has caused
different areas to become dryer frogs begin to dry
out and eventually die.
 12.The graph on page 12 shows the decline of
frogs in an area where deforestation occurred
between 1985 and 1986.