Those that are extant but threatened by extinction are referred to as threatened or endangered species. By Michael Evans - Sun, 29 May Within these captive-breeding programs, species are bred with the hope that offspring can be raised and then returned to the wild. And of course there are equally justified arguments for keeping species based purely on their aesthetic and cultural importance, or for their own sake.
For this, we need to work hard on preventing species extinction. And although some de-extinctionists insist that the knowledge we gain from de-extinction science may help us to save current species, this is a very dicey premise given the dire situation of the current mass extinction.
Several species have also been listed as extinct since Within a short time they had wiped out several of the island's native birds and other fauna. If we want to avert extinctions from our legacies we will need to direct conservation efforts most into areas carrying the highest debts.
Modern elephants have a difficult time reproducing in captivity already. Preventing existing endangered species from going extinct should take precedence over reviving species already lost.
The main cause of habitat degradation worldwide is agriculture, with urban sprawl, logging, mining and some fishing practices close behind. Instead, the foxes killed off native Australian marsupials.
Other species that are not in immediate danger but that have small populations and so could move quickly toward extinction are called vulnerable or candidate species. Pseudoextinction is much easier to demonstrate for larger taxonomic groups. There are a variety of causes that can contribute directly or indirectly to the extinction of a species or group of species.
Some of these species are already menaced by the loss of their habitats. Pollution is a major disrupter and destroyer of ecosystems and this was graphically illustrated following the April Deepwater Horizon oil disaster in the Gulf of Mexico.
The dodo of Mauritiusshown here in a illustration by Roelant Saveryis an often-cited example of modern extinction  Currently an important aspect of extinction is human attempts to preserve critically endangered species.
This has unknowingly led to a decrease in their reproduction and hence put them on the endangered list. A spike in extinction rates was solely responsible for the end-Ordovician, end-Permian and end-Cretaceous events, but a drop in rate of evolutionary origin of new species also seems to have contributed to the late Devonian and end-Triassic events.
On a worldwide basis, the resulting rise in sea levels can disrupt the ecosystems of many species, including humans. By conservative estimate, this destruction means that 50 to species in the tropics become extinct each day.
Human activity is releasing harmful chemicals into the air, water and soil all over the planet. There is no way of knowing how many undiscovered treasures have been lost to extinction. In one month, it is estimated that between 30 and 1, species disappear.
In one day alone, we can say good-bye to at least one plant or animal species. Calculating extinction rates can be difficult, in part because no one knows exactly how many species there are. Scientists have identified at.
Current rates of extinction, however, are estimated to have reached to 10, times this rate. Put bluntly, the annual species body count is no longer a. Problem: Extinction of Plant and Animal Species Massive extinctions have occurred five times during the earth's history, the last one was the extinction of the dinosaurs, 65 million years ago.
Scientists are calling what is occurring now, the sixth mass extinction. Problem of the extinction of many rare species The problem of the extinction of many rare species is becoming more and more serious in the recent years, so the governments of the world have established many nature reserves to protect these species.
Chongming Dongtan Nature Reserve is one of the most important wetland kinds of national nature reserves. There are many examples of co-extinction, but the most common is that of the dinosaurs.
When the climate of the Earth changed very suddenly many of the plants died, which resulted in the loss of herbivorous (plant eating) dinosaurs.Problem of the extinction of many