Extinction in biology means the loss of existence of a species or group of the taxon. The extinction time of a species is marked by the death of the last individual of the species, although the ability to breed is no longer present. But because the distribution of a species or taxon can be very large, it is very difficult to determine the time of extinction. This difficulty can lead to a phenomenon called Lazarus taxon, in which a species is considered extinct but reappears.
In biology and ecology, extinction is the termination of an organism or of a group of organisms (taxon), normally 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 at 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. [1]
Extinction is an event of loss of the whole species. Extinction is not an uncommon event because species regularly appear through speciation and disappear through extinction.In fact, almost all the species of animals and plants that once lived on earth have become extinct, and extinction seems to be the ultimate fate of all species. Extinction has occurred continuously throughout the history of life, although sometimes the rate of extinction has increased sharply in the event of mass extinction.
In the history of the earth has been recorded five times mass extinction event, this occurred during the Cambrian, Ordovician, Devonian, Permian, and Cretaceous. Among the five mass death events, the events of mass death in the Permian period are the most abundant events in earth's history.
At that time it reached about 70% of extinct organisms. However, during Cretaceous times before mass events, the number of living organisms has exceeded the circumstances before the Permian death. After the death of Cretaceans, now the number of organisms is still increasing again so that the estimated number of organisms has doubled from the state before the events of Permian death.
Terry Gates, a joint postdoctoral researcher with NC State and the North Carolina Museum of Natural Sciences, and colleague Rodney Sheetz from the Brigham Young Museum of Paleontology, came across the fossil in storage at BYU. First excavated in the 1990s from Utah's Neslen formation, Rhinorex had been studied primarily for its well-preserved skin impressions. When Gates and Sheetz reconstructed the skull, they realized that they had a new species. "We had almost the entire skull, which was wonderful," Gates says, "but the preparation was very difficult. It took two years to dig the fossil out of the sandstone it was embedded in -- it was like digging a dinosaur skull out of a concrete driveway."
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After the world was struck by the discovery of the largest dinosaur in Argentina and the ancient animal spinosaurus Spinosaurus, the largest dinosaur with the largest nose, Rhinorex condrupus was discovered. Formerly living in an area that is now a city of Utah in America. Rhinorex lived in the late Cretaceous period, a chalk era about 80 million years ago.
Rhinorex can be defined as "King of the Nose", plant-eating animals and close relatives of Parasaurolophus and Edmontosaurus. This nose king was discovered by researchers from North California State University and Brigham Young University. Its length reaches 30 feet and weighs four tons. Terry Gates, a researcher from NC State said, "If this dinosaur had such a large nose size he might have had a remarkable olfactory."
The usefulness of the big nose of Rhinorex remains a mystery. It does not close the possibility of hiding magnitude as the attraction of the opposite sex, the identity of the species, even as a means of destroying food. The whole skull and the results are amazing, "Gates said. It took two years to remove Rhinorex fossils from the Land. Rhinorex used to live in swampy areas, about 50 miles from the coast. This dinosaur was the only herbivorous living-living herbivorous dinosaur in the Cretaceous / lime period-found with the complete fossils.
From a study conducted by researchers from England, it can be concluded that the methane gas released by the dinosaurs that caused the extinction of these giant animals. According to calculations, the prehistoric creatures have been blowing more than 500 million tons of methane a year into the air. This figure is enough to warm the planet Earth and accelerate their own extinction.
Until recently, asteroid blows and volcanic activity around 65 million years ago were mentioned as the cause of the extinction of dinosaurs. However, in a study published in the journal Current Biology, the plant-eating giant sauropod is a species accused of causing it.
As an illustration, an argentinosaurus weighs about 90 tons and has a length of 42 meters, averaging half a ton of ferns per day. He will produce a lot of methane as he decomposes the food in the gastrointestinal tract, then releases the gas through the sewer.
The production of dinosaurs' methane reaching 500 million tons per year is proportional to the current and human-caused greenhouse gas emissions. The amount can be predicted about 21 times stronger than CO2 in trapping heat temperatures on Earth's surface and causing climate change. By comparison, cattle and livestock that exist around the world today only produce 100 million tons of methane per year.
A partial skeleton of the new dinosaur, including a skull and teeth, was discovered on a beach near Cardiff. It was analyzed by a team of UK scientists led by Dr. David Martill from the University of Portsmouth, and was identified as a new species and genus of the theropod dinosaur. “Approximately 40% of a skeleton including cranial and postcranial remains representing a new genus and species of basal neotheropod dinosaur is described,” Dr. Martill and his colleagues from the Amgueddfa Cymru – National Museum Wales, the University of Manchester, and the University of Portsmouth, wrote in a paper in the journal PLoS ONE. “It was collected from fallen blocks from a sea cliff that exposes Late Triassic and Early Jurassic marine and quasi marine strata on the south Wales coast near the city of Cardiff.”
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A partial skeleton of new dinosaurs, including skulls and teeth, was found on a beach near Cardiff. The findings were analyzed by a team of British scientists led by Dr David Martill of Portsmouth University. As a result, the dinosaur fossils were identified as new species of the Theropod dinosaur genus.
"Approximately 40% of the skeletons (including skull remnants and beyond the skull) represent genera and new species from the basal image of the Neotheropod dinosaur," Dr. Martill and his colleagues from Amgueddfa Cymru - National Museum of Wales, University of Manchester, and Portsmouth University. They reveal it in a paper in the journal PLoS ONE.
But the estimate is based on scattered evidence. For Argentinosaurus, for example, only a few spinal, hip bones and some other bones are found. The giant's tailbone, Therefore, the discovery of Dreadnoughtus is greeted with joy.
Although his skull did not last, almost half of the remaining skeletons were preserved. And if you look at only the main bones, more than two-thirds of the animals appear intact in the form of fossils. Thus Dreadnoughtus offers a new "window" to look at the anatomy, biomechanics, and evolution of titanosaurs. Of course, this could trigger debate about which one is really the biggest dinosaur.
REFERENCE
EndNote:
1. Extinction wikipedia source
2. Releases source
3. New species dinosaur wales source