Megalodon is now considered to be a member of the family Otodontidae, genus "Carcharocles". Megalodon's older classification into "Carcharodon" was due to dental similarity with the great white shark. Most authors now think this is due to convergent evolution. The great white shark is more closely related to the extinct broad-toothed mako ("Isurus hastalis") than to megalodon. The dentition in those two sharks is similar, whereas megalodon teeth have much finer serrations than great white shark teeth. The great white shark is more closely related to the mako shark ("Isurus" spp.), with a most recent common ancestor about 4 mya. Those who still think megalodon and the great white shark are more closely related, argue that the differences between their dentition are minute and obscure.
Dust Bowl
The "Dust Bowl" is a phrase used to describe prairie regions of the United States and Canada in the 1930s. The Dust Bowl spread from Saskatchewan and Manitoba to the north, all the way to Oklahoma and parts of Texas and New Mexico in the south. In these areas, there were many serious dust storms and droughts during the 1930s. These caused major damage to the Dust Bowl areas' economies, ecology, and agriculture. The dust bowl was the worst man made disaster in U.S history. It was many dust storms that happened for many years.
The people who lived in the Dust Bowl area were mostly farmers. Many years of intense farming without rain left the soil dry. When strong winds blew, they covered cities, towns, and farms in dried, dusty soil, ruining the farmland.
One famous storm on April 14, 1935, called "Black Sunday", was so bad it covered dozens of cities in black clouds of dust and made it impossible to see the sky or even a few feet ahead. Writer Timothy Egan says that the Black Sunday storm "carried away twice as much dirt as was dug out of the earth to create the Panama Canal."
The Dust Bowl period is still considered one of the worst environmental disasters in United States history. Many thousands of people died from breathing in the dust, or from starvation. Many others who survived lost everything they had, and left the Dust Bowl to look for work in other parts of the country. These people were called "Dust Bowl refugees."
The seriousness of the Dust Bowl disaster later led to greater use of crop rotation, reforesting and other techniques to preserve the quality and quantity of topsoil in American and Canadian farms. Many songs, books, and works of art were created to tell stories of the people affected by the dust storms. Some of the most famous of these works are the novels "The Grapes of Wrath" and "Of Mice and Men", by John Steinbeck, the songs of folk music singer Woody Guthrie, and the photography of Dorothea Lange, who took pictures of many Dust Bowl refugees and their families.
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Passionfruit
The Passionfruit (also spelled passion fruit) is a small, spherical fruit. It is purple when ripe, and green when not ripe. The fruit contains many small, black seeds covered with the fruit's flesh. It is tart and sweet. The seeds can be eaten on their own or used for various cooking recipes. Passion fruit is not a very common fruit in England.
Mosasaur
Mosasaurs were large, predatory marine lizards of the Upper Cretaceous. The first fossil Mosasaur, "Mosasaurus hoffmanni", was found in the Netherlands in 1776. It was named in 1822 by W.D. Conybeare.
The type specimen was found in a chalk quarry in Maastricht, Holland. It was found by a German army surgeon, Johann Hoffmann, who collected fossils for the Haarlem Museum. During a struggle for ownership, the skeletal parts went to the museum, whilst the skull stayed with the owner of the land, who refused to let anyone see it.
The true identity of the monster was decided correctly by the French anatomist Georges Cuvier. In 1795 French troops were outside Maastricht, and Cuvier arranged for the large skull to be saved when they stormed the town. The skull duly went to Cuvier in Paris, because he was the leading comparative anatomist of the day. He recognized the skull as that of a giant lizard, from its teeth and skull bones, though not until 1808, and by then the son of a Dutch professor, Adriaan Camper, had already had the same idea. The discovery of the specimen was important in another way, because it helped to convince Cuvier that extinction of some species was a fact. Cuvier later came up with a catastrophism-type theory.
Mosasaurs breathed air, were powerful swimmers, and were well-adapted to living in the warm, shallow epicontinental seas of the Upper Cretaceous. Mosasaurs were so well adapted to this environment that they gave birth to live young, rather than return to the shore to lay eggs, as sea turtles do. Thousands of fossils have been found, from every continent. There are about 40 known species. Most skeletons have been found in North America in chalk laid down in the Western Interior Seaway.
An interesting fact is that ichthyosaurs had died out by the middle of the Upper Cretaceous, and plesiosaurs and sea-going crocodiles were in decline. The reasons for this are not known: perhaps there was increased competition from large predator fish. It is this large marine predator niche that mosasaurs apparently occupied. They gave birth to live young, just as the ichthyosaurs had done. They flourished in the later Cretaceous, only to become extinct at the K/T extinction event.
The type species was estimated to be 33' (10m) long. "Mosasaurus" had four paddle-like limbs on a long, streamlined body and a long, powerful tail. The large head had huge jaws, up to 4 ft (1.2 m long) with many teeth. The jaws could open about 3 feet (1 m). The lower jaw is loosely hinged to the skull with a moveable joint on each side (behind the teeth). This loose joint let it swallow huge prey. They would have hunted fish, turtles, molluscs, and shellfish. Ammonites have been found bearing mosasaur teeth marks.
The smallest-known mosasaur was "Carinodens belgicus", which was about to long and probably lived in shallow waters near shore, cracking molluscs and sea urchins with its bulbous teeth. Larger mosasaurs were more typical: mosasaurs ranged in size up to . "Hainosaurus" holds the record for longest mosasaur, at .
Scientists have wondered whether ancient reptiles like mosasaurs were warm-blooded or cold-blooded. Scientists from the University of Plymouth studied many animals that dive and hold their breath, from insects to whales. They found that larger animals can hold their breath longer than smaller animals because they can store more oxygen for their size, and they found this difference was much bigger for warm-blooded animals than for cold-blooded animals. They said this could be why modern whales became so large. They concluded that the large size of mosasaurs, like whales, meant they were more likely to be warm-blooded than cold-blooded.
Many other species of mosasaur have since been found, for example, "Tylosaurus". "Mosasaurus maximus" was found at Onion Creek, Texas. All have the same general body style and pattern of life, though some, like "Prognathodon", had crushing teeth for dealing with shellfish. Present thought is that their closest living relatives are the monitor lizards.
Nevermind
Nevermind is the second studio album by the American rock band, Nirvana. It was released on September 24, 1991 by DGC Records. It was produced by Butch Vig and was the first release by the band on the record label. It was also the first release with drummer Dave Grohl.
Even though it wasn't thought to have been very popular before its release, "Nevermind" was a very big success. On January 11, 1992, it had reached number one on the US "Billboard" 200. The main single, "Smells Like Teen Spirit" was very successful and reached number six on the "Billboard" Hot 100. The three other singles were: "Come as You Are", "Lithium", and "In Bloom". "Nevermind" was selling up to 300,000 copies a week between 1991 and 1992.