The declarations of the extinction of many species turn out to be inaccurate
Andrew Rivkin
Scientists studying the rainforests, rivers, coral reefs,
Deserts and islands across the planet are increasingly encountering a new species
of biological species: the dead-the living. They still exist, but they are important
as extinct.
It turns out that many biological species, of which a tiny number of individuals remain,
Somehow find ways to adapt, even if temporarily, to the sweeping changes
in their environment. The process of extinction is longer and more complex than many biologists
They are used to thinking, and sometimes the possibility arises that a biological species that is disappearing
will return and gain a foothold in his environment.
Some, like the Puerto Rican parrot, whose population seems to have succeeded
To reproduce somewhat after being reduced to only 12 individuals, they are indeed capable
to recover Other species fail to do this, although many biologists do
We come to their aid. "When you see great animals and plants, and you know
That you might be one of the last to see them, you are overwhelmed with feeling
A tremendous loss," says Dr. Stuart Pym, an expert on the extinction of species
Biology at Columbia University. It is quite similar to observing soon
Old family and loved one who is about to die. You don't know exactly when Uncle Joe
The elderly will be overwhelmed and die."
The stubbornness of species on the brink of extinction sometimes creates embarrassment in battle
Ecologists and biologists specializing in species conservation. Two decades ago they predicted
Many experts, that by the year 2000 about 20% of the biological species in the world
will become extinct It did not happen, and among ecologists there is a growing recognition that it is over
For many species, the game is not as direct and unambiguous as it is
Depicted in the mathematical models. These models, which predict extinction rates,
Based on the following data: the density of a biological species in the habitat
its and the speed with which the habitat is destroyed (usually by man).
The discrepancy between theory and reality led some biologists
Call for a change in the method in which environmentalists describe the process
extinction, and to change the way scientists study it.
A growing group of scholars argue that giving far-reaching statements
sect, which compares the current extinction events to the extinction of
The dinosaurs 65 million years ago. These comparisons, they say,
express certainty that does not exist in science. They add that the scientists
To emphasize that the extinction process extends over a period that is very difficult to measure or
Appreciate. "When it comes to the extinction of species, we have to forget about the time scale
the human one," says Dr. John Ellroy, an ecologist at the University of California
in Santa Barbara. "For a biological species, a human life span is a fraction
second".
A major problem that frustrates the scientists studying the existing species
Endangered is that they are not aware of all the biodiversity on the globe
Country. There is a huge gap between the number of species sorted by science -
Less than 2 million - and the estimate of the number of all existing species:
Between 7 million and more than 100 million, depending on who is counting.
Last year Dr. Ross McPhee, Curator of Mammals at the Museum of History surveyed
of Nature in Washington, the "Red List" of the Conservation Union
the world, a report published every four years, in which all species are detailed
which were declared extinct. McPhee found dozens of mistakes in the list: species that appeared
In the list, even though they are not extinct, and extinct species that the report did not mention. Analysis
A separate analysis of the fish extinction data yielded similar findings.
Some biologists claim that the concern regarding the current turmoil in the world
Nature needs to soften with the help of raising awareness that big changes -
Including extinction and new biological differentiation - they are an essential element of life
on the surface of the earth.
Puerto Rico, for example, 97% of its forests disappeared in the centuries after colonization
The European one, returned in the last decades to be forested, and now they live in it
Local species alongside exotic species. The ginkgo tree is almost extinct
in its original home in China, and was preserved only in a few monasteries. It is now common
around the world and managed to establish itself in some environmentally unfriendly places.
Brooklyn, for example. It turns out that with a little help, many species manage to get up
from the boards
(Originally published on 23.10)
© Published in "Haaretz" on 10/31/2000
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