|
Changes
in Resources
A
brief change in the limited resources of an ecosystem may
alter the size of a population or the average size of individual
organisms and that long-term change may result in the elimination
of animal and plant populations inhabiting the Earth.
Changes
in limited resources
Have you ever been to an amusement park and a ride that you
really wanted to go on is broken down? What if this happens
several times at the same park? If a main attraction to an
amusement park breaks down, it might make some people leave.
If this happens the rating of the park will go down, probably.
Some people may never come back, and others may not return
as much as they would usually. The system has broken down.
Well this is pretty much the same thing that happens in an
ecosystem.
Changes
to an ecosystem
Humans can and do alter ecosystems. One example of this is
over-fishing. If certain species are overfished, their numbers
grow smaller and other species loose part of their foodchain.
So on and so forth. It causes a chain reaction.
Endangered
and Extinct Species
Long-term change many lead to the elimination of animal and
plant populations. Many species are endangered or extinct
because of several factors. These factors include:
- the
destruction of their habitat (both natural and man-made)
- interlopers:
species that are not naturally of a habitat that are introduced
to that habitat (e.g. rats, cats, insects)
- overexploitation:
for example, overfishing.
|
