Archive for the ‘Extinct Species’ Category
Comet hit killing Mammls questioned
March 23rd, 2010 | 
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The theory that a huge comet hit might have generated huge forest fires, which stands as a reason of extinction of the oldest creatures, mammals has been questioned as there are new developments which are suggesting that it might not be the main reason for their extinction.
A group of reasearchers who have been working in finding what caused the extinction of the fauna from the phase of the earth hundreds of years ago have recently come across reports of coal samples that have been collected from the rivers believed to be deposited since 12 900 years, the time huge mammals existed and found that there are no signs of huge continental scale fire on it.
This brings forth doubts that was it the comet hit the main reason for the fauna to disappear or is there some other reasons as well which might have fuelled the happening.
But no solid evidence has yet been developed to prove this hypothesis completely, but taking this as the initial link, scientists are researching more into the matter.
Tasmanian tiger’s mystery – Uncovered
Tasmanian tiger’s mystery – Uncovered
Since the last known surviving Tasmanian tiger died in the Tasmanian zoo in 1936, the animal has been in the list of extinct animal for the past 73 years. Little was understood about the family line of the animal until recent studies are conducted to uncover the unknown.
With the advancement in DNA technology, researchers are finally able to fully mapped the DNA sequence of Tasmanian tigers. This in terms could help researchers in understanding family line of the animal, as well as providing information relating to the process of their extinction. The Tasmanian tiger, also called the thylacine, is believed to have been in the path of extinction much earlier. According to Webb Miller, who led the study, the thylacines were eliminated from mainland Australia as early as 3,000 years ago due to the competition from dingos. By 1930s, bounties were introduced to curb thylacine’s predation on sheep. Eventually, a deadly disease caused their population to plunge in the 1900 to 1910.
DNA sequencing by Miller and his team discovered that there is an ultra-low genetic diversity in thylacine. The DNA analysis also affirmed thylacine as being a species crossed between a dog and a tiger. However, it was a marsupial more closely related to insect-eaters called numbats, and a distance relative to kangaroos and koalas.
Archaeopteryx one of the earliest birds had a very poor hearing ability
Scientists have concluded that Archaeopteryx lithographica the earliest bird had a hearing ability similar to the modern emu, which is known to have the lowest of hearing ranges.
A team of scientists have conducted several experiments on various specimens (reptiles and birds) and have come to a conclusion that by determining the length of a particular inner part of the ear one can actually determine the hearing ability of the reptiles and modern birds.
Based on these observations the scientists have come to know that the living reptiles have a poor hearing when compared the modern birds.
A long cochlear duct indicates that the animal has a clear and healthy hearing and it also indicates that the creature has a very healthy vocal communication.
Scientists used the same technique to determine the hearing ability of Archaeopteryx, one of the earliest birds. Scientists have observed that the bird had a 2000 Hz hearing ability which is regarded as a poor hearing ability according to the modern bird standards.
Early feathers of dinosaurs were nothing but ornaments
A study led by Xing Xu at Chinese academy of Sciences, prove that the early feathers on dinosaurs were
just a token of display and nothing else.
The team led by Xing Xu has found a 125 yea old Dinosaur fossil, which belonged to Beipiaosaurus (an early
species of theropods) in the north east china which was believed to be a part of one of the oldest
dinosaur species Theropods.
A different kind of feathers was witnessed by the team on this 125 year old fossil, which they believe
wasn’t used for either for flying nor for staying warm.
When compared to the feathers observed on other theropods that have been discovered during so many years these feathers are considerably small and slender. Basically fit for neither flying nor generating warmth.
Adding to it the feathers were found on that part of the body, where one finds ornaments on the modern
birds. This led to the conclusion that the first feathers of dinosaurs were for nothing more than visual display.
Scientists recovered details about Tasmanian tigers through its DNA
Scientists succeeded in collecting details about an extinct animal named “Tasmanian Tiger”.
These creatures ceased from existence in the early nineties. These were mostly found in the Australian
territory.
A group of scientists managed to extract DNA samples from the hair of these animal preserves found at
Swedish and US museums.
The Tassie Tiger officially known as Thylacinus cynocephalus depicted a dog in the way it looked and had a
few similarities of cat like the stripes on its body.
According to the scientists the DNA samples that they have collected from the last two creatures had
identical DNA.
Scientists say that hunting was regarded as the reason why the animal species went extinct, but the DNA
study of the animals suggests that the existence of the species was never intended to last long.
The last of the animals died in Hobart Zoo in 1936 after which no one has ever seen another Tasmanian
tiger.
Christmas Island’s native rats wiped out by pathogens
Christmas Island’s native rats wiped out by pathogens
Scientists have found that native rat species, Rattus macleari and R. nativitatis, belonging to Australia’s Christmas Island have been wiped out entirely by a type of pathogen. The research was done via DNA means in both the extinct native rats.
The extinction could be dated back to between 1899 and 1908, where Hindustan first brought in the black rats to the island in 1899. The black rats, also named ship-jumping black rats, were at that time carrying a protozoan known as Trypanosoma lewisi. A related organism causes sleeping sickness in humans. Soon, the protozoan was spread via fleas between the different species of rats, leading to the dying of both the native rat species. Shortly thereafter, both native species were never seen again.
Comparison between DNA samples of native rats at two different periods, before and after black rats were introduced, suggests that a type of protozoan have led to their extinct.
Scientists have found that native rat species, Rattus macleari and R. nativitatis, belonging to Australia’s Christmas Island have been wiped out entirely by a type of pathogen. The research was done via DNA means in both the extinct native rats.
The extinction could be dated back to between 1899 and 1908, where Hindustan first brought in the black rats to the island in 1899. The black rats, also named ship-jumping black rats, were at that time carrying a protozoan known as Trypanosoma lewisi. A related organism causes sleeping sickness in humans. Soon, the protozoan was spread via fleas between the different species of rats, leading to the dying of both the native rat species. Shortly thereafter, both native species were never seen again.
Comparison between DNA samples of native rats at two different periods, before and after black rats were introduced, suggests that a type of protozoan have led to their extinct.
Christmas Island’s native rats wiped out by pathogens
Caribbean monk seal officially extinct
Caribbean monk seal officially extinct
A status review [under the Endangered Species Act] was done which affirmed that Caribbean monk seal is now officially extinct. The seal, covered in brown fur tinged with gray, and with a yellow belly, was the only subtropical seal native to the Caribbean. There are two other species of monk seal, however, both are being classified as endangered with only 1,200 and 500 seals remaining respectively.
The history of Caribbean monk seal extinction can be traced back to the 1600s and 1700s, where they were preyed by the European settlers for meat, oil, and be used to seal bottoms of boats. Eventually by the 1800s, their population falls to such a small group whereby sightings of them were rare. The seal was last seen on a group of reef islands between Jamaica and Mexico’s Yucatan Peninsula. Though there have been reports of several sightings since they last appeared in 1952, it was hard to verify the reliability of those sources. Other sightings were verified to be seals of other species, such as hooded seals, bearded seals, and harbor seals.
As for the now endangered Hawaiian monk seal, its population is believed to plunge below 1,000 in the next couple of years. The declination is approximately 4 percent per year. The seals were threatened with habitat loss, limitation in food, marine debris and shark predation. Plans to conserve the animal are undergoing, though much efforts need to be done.
With the lost of Caribbean monk seal, conservationists pledged to conserve the already endangered Hawaiian monk seals.
Scientists found fossils of extinct species in Saharan desert
Scientists claim that they have managed to un earth two extinct species which are among the 50 species which were never been able to trace.
A group of British and Moroccan scientists went searching for fossils in the Saharan desert.
The group which included a lot of paleontologists has confirmed that these fossils belonged to important species namely: New species of pterosaur, a flying reptile from the Mesozoic era, and a new type of sauropod, a giant four-legged herbivore from the Jurassic period.
A large beak of the giant flying reptile was unearthed along with bones, of a sauropod which was reported to be atleast 3.3 feet in length.
The groups of scientists claim that this discovery of recovering two fossils at one time is really a great achievement so far by them
Oldest web has been discovered by scientists
The world’s oldest web has been discovered by the scientists.
Scientists believe that this web belongs to the era which existed about 140 millions of years ago.
Oxford University pale biologist Martin Brasier is leading a research on this new discovery.
He believes that arachnids have been using their silky nets since the dinosaur age.
It has been observed that the pattern in which the webs have been linked to each other matches the gardeners’ worlds over.
This spider web was traced in a pre historic piece of amber which was collected by an amateur fossil hunter in England around two years ago.
A microscopic observation of the sample has revealed that there are webs in it which were 2 mm in diameter and were found buried inside the piece.
Search is set to find traces of the extinct Ivory billed woodpecker
Ivory billed woodpecker, the elusive bird which was believed to be extinct is believed to be still around.
Allan Meuller thinks he has seen the bird in the swamps of Eastern Arkansas, where he was camping.
To confirm the existence of the bird Allan set a search to the swamps of Eastern Arkansas with 26 volunteers and three skilled biologists.
According to the biologists the ivory bill is most active in March and April, which is its nesting period.
The group will set forward for its search from this weekend.
There have been many groups earlier who have tried to trace the existence of the ivory bill, but failed. Ignoring such things Allan is confident that his team will trace the black and white woodpecker.
The search for the bird first started four years, when it is believed that the bird has first showed its existence to the world. Scientists and biologists have been trying desperately to find the bird’s trace.
