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Human beings have a part extinct birds becoming extinct
Human beings have a part in extinct birds becoming extinct. They often kill a species of bird or other animal for food, clothing, for profit from specific pieces of the animal, or for their personal collections. Within the last 280 years or so, 42 species and 44 subspecies have become extinct. Hawaii has lost 9 species and 7 species within the last 200 or so years and North America has lost 2 bird species and 3 subspecies. Ratites are large, flightless birds that are characterized by their breastbone, which looks like a raft. Flightless birds are those birds that rely on their ability to swim or run, considering they have lost the ability to fly.
Flightless birds also have more feathers than their flying counterparts. Ratites differ from other flightless birds in that they have no keel on their sternum. This means that even if they did develop wings to fly, they would be unable to do so, for they lack a strong anchor for suitable wing muscles. Most of the ratite birds are now extinct birds.
The ratite group of living birds includes the ostrich, emu, cassowary, kiwi, and rhea. The kangaroo island emu, the king island emu, the moa (Dinornis giganteus), Elephant bird (Aepyornis maximus), and the diatryma are all extinct birds. The King Island Emu was discovered on King Island (thus its name), which is located between Australia and Tasmania. It is believed these ratite birds became extinct due to hunting and to fires started on the island by sailors passing through. The elephant bird was a giant ratite native to Madagascar. It is believed to be extinct since around the 16th century. It is believed by some that these large extinct birds became extinct as a result of human actions. It is speculated that when people arrived on the island of Madagascar, they harvested the elephant bird eggs for food. It is also possible that with the introduction of rats and dogs (who accompanied the colonists). The elephant egg population was reduced as the animals preyed upon them. Two other theories have been suggested as to the cause of the extinction of the elephant bird. One is that humans hunted and killed them for meat. The other is that a climate change occurred in Madagascar (intense drying out of the land), which would have contributed to a lack of available food and water. The extinction of some ratite birds is a mystery, but we can usually point to climate, human beings or other predators as either the single cause or a combination of factors which brought about the loss of these amazing species. When they say that a species or animal is extinct, what does that actually mean? If an animal, or bird, is extinct, it means that there are no longer any species of that animal alive any where in the world. To determine whether or not a species is in fact extinct, it is crucial that all attempts possible be made to locate the species and that there have not been any confirmed sightings of the species for many years. There have been many cases where a species was declared extinct, but in fact they were not! Sometimes a group of animals are significantly reduced in their number as a result of lack of food or a poor breeding season. Other times, the species may simply reside in an unpopulated and remote area and so haven't been seen for long periods of time and therefore thought to be extinct. One such example is the takahe, which hadn't been sighted for over 50 years and thought to be on the extinct birds list. However, a man by the name of Geoffrey Orbell found the bird in 1948, living in a remote Fiordland valley. What causes a species to become extinct? Many times it is a combination of factors. Environmental changes can be a factor. Climates or an animals' habitat can be altered or changed, causing a reduction in breeding or a lack of food. When people clear forests, thereby destroying the species' habitat and killing the animals in the process, the species has no place to live and eventually die off completely. Predators can have an affect on an entire species by killing all of them. For example, when humans arrived in New Zealand many years ago, they brought with them new predators, such as pigs, cats, dogs, and rats. They killed and ate birds, ate the bird eggs, and consumed the birds' food source. If there is competition for the same food source and a species is unable for whatever reason to find it elsewhere, they could become extinct.
the dodo bird is one of the extint birds
the kakoka
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