Extinction is forever, endangered means we still have time. Save the endangered species.

 Bird conservation is a field in the science of conservation biology related to threatened birds. Humans have had a profound effect on many bird species. Over one hundred species have gone extinct in historical times, although the most dramatic human-caused extinctions occurred in the Pacific Ocean as humans colonized the islands of Melanesia, Polynesia and Micronesia, during which an estimated 750–1800 species of bird became extinct. According to World watch Institute , many bird populations are currently declining worldwide, with 1,200 species facing extinction in the next century. The biggest cited reason surrounds habitat lossOther threats include overhunting, accidental mortality due to structural collisionslong-line fishing bycatch, pollution, competition and predation by pet catsoil spills and pesticide use and climate change. Governments, along with numerous conservation charities, work to protect birds in various ways, including legislation, preserving and restoring bird habitat, and establishing captive populations for reintroductions.

Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point. Because a species' potential range may be very large, determining this moment is difficult, and is usually done retrospectively. This difficulty leads to phenomena such as Lazarus taxa, where a species presumed extinct abruptly "reappears" (typically in the fossil record) after a period of apparent absence.

More than 99% of all species that ever lived on Earth, amounting to over five billion species,[1] are estimated to have died out.[2][3][4][5] It is estimated that there are currently around 8.7 million species of eukaryote globally,[6] and possibly many times more if microorganisms, like bacteria, are included.[7] Notable extinct animal species include non-avian dinosaurssaber-toothed catsdodosmammothsground slothsthylacinestrilobites and golden toads.

                                                           Labrador duck ( Camptorhynchus labradorius)



 New Zealand quail (Coturnix novaezelandiae)

The truth is, scientists don’t know how many species of plants, animals, fungi, and bacteria exist on Earth. The most recent estimate put that number at 2 billion, and that will most likely change at some point.

One thing we do know: The western black rhinoceros, the Tasmanian tiger, and the woolly mammoth are among the creatures whose populations at one point dwindled to zero, and it’s possible that species extinction is happening a thousand times more quickly because of humans.

Extinction happens when environmental factors or evolutionary problems cause a species to die out. The disappearance of species from Earth is ongoing, and rates have varied over time. A quarter of mammals is at risk of extinction, according to IUCN Red List estimates.

To some extent, extinction is natural. Changes to habitats and poor reproductive trends are among the factors that can make a species’ death rate higher than its birth rate for long enough that eventually, none are left.

Humans also cause other species to become extinct by hunting, overharvesting, introducing invasive species to the wild, polluting, and changing wetlands and forests to croplands and urban areas. Even the rapid growth of the human population is causing extinction by ruining natural habitats.

Among the most famous species driven to extinction by humans is the dodo, a bird that primarily lived in the island nation of Mauritius and was popularized by its appearance in Lewis Carroll’s book “Alice’s Adventures in Wonderland.” Dodos were first mentioned by Dutch sailors in the late 16th century and last seen in 1662 after having been hunted to extinction. Passenger pigeons, billions of which frequently blanketed North American skies when Europeans arrived on the continent, went extinct when the last one died at the Cincinnati Zoo in 1914.

                                                                Tahiti rail

                                                        Great auk (Pinguinus impennis
                                    



Once a species has gone extinct, it never reappears on Earth again.

Harvard geneticist George M. Church, believe that ongoing technological advances will let us "bring back to life" an extinct species by cloning, using DNA from the remains of that species. Proposed targets for cloning include the mammoth, the thylacine, and the Pyrenean ibex. For this to succeed, enough individuals would have to be cloned, from the DNA of different individuals (in the case of sexually reproducing organisms) to create a viable population. Though bioethical and philosophical objections have been raised, the cloning of extinct creatures seems theoretically possible.

In 2003, scientists tried to clone the extinct Pyrenean ibex (C. p. pyrenaica). This attempt failed: of the 285 embryos reconstructed, 54 were transferred to 12 mountain goats and mountain goat-domestic goat hybrids, but only two survived the initial two months of gestation before they too died. In 2009, a second attempt was made to clone the Pyrenean ibex: one clone was born alive, but died seven minutes later, due to physical defects in the lungs.



Extinction is forever, endangered means we still have time.



THANK YOU !

By : NEHA

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