Himalayas were born 47 mn years ago

Sydney/Washington: An international team of scientists has discovered the first oceanic microplate in the Indian Ocean— identifying when the initial collision between India and Eurasia occurred leading to the birth of the Himalayas. The team of Australian and US scientists believe the collision occurred 47 million years ago when India and Eurasia initially smashed into each other. Although there are at least seven microplates known in the Pacific Ocean, this is the first ancient Indian Ocean microplate to be discovered. "The age of the largest continental collision on Earth has long been controversial. Knowing this age is particularly important for understanding the link between the growth of mountain belts and major climate change," said lead author Dr Kara Matthews from University of Sydney's school of geosciences. Radar beam images from an orbiting satellite have helped put together pieces of this plate tectonic jigsaw and pinpointed the age for the collision, whose precise date has divided scientists for decades. The new research shows that 50 million years ago, India was travelling northwards at speeds of some 15 cm a year — close to the plate tectonic speed limit. Soon after, it slammed into Eurasia crustal stresses along the mid-ocean ridge between India and Antarctica intensified to breaking point. The crustal stresses caused by the initial collision cracked the Antarctic Plate far away from the collisional zone and broke off a fragment the size of Australia's Tasmania in a remote patch of the central Indian Ocean. "Dating this collision requires looking at a complex set of data but we have added a new observation which has not been previously used to unravel the birth of this collision," explained professor Dietmar Muller in a statement from University of Sydney. The authors, including professor David Sandwell from Scripps Institution of Oceanography in the US, have named the ancient Indian microplate as the Mammerickx Microplate — after Dr Jacqueline Mammerickx, a pioneer in seafloor mapping. The ongoing tectonic collision between the two continents produces geological stresses that build up along the Himalayas and leads to numerous earthquakes every year. According to professor Sandwell, humans had explored and mapped remote lands extensively but the same was not true for our ocean basins. "We have more detailed maps of Pluto than we do of most of our own planet because about 71 percent of the Earth's surface is covered with water," Sandwell added. The advances in comparatively low-cost satellite technology are the key to charting the deep, relatively unknown abyssal plains, at the bottom of the ocean, he pointed out. The paper was published in the journal Earth and Planetary Science Letters. — IANS. Source: Article
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Venus flytrap


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The Venus flytrap (also Venus's flytrap or Venus' flytrap), Dionaea muscipula, is a carnivorous plant native to subtropical wetlands on the East Coast of the United States. It catches its prey—chiefly insects and arachnids— with a trapping structure formed by the terminal portion of each of the plant's leaves and is triggered by tiny hairs on their inner surfaces. When an insect or spider crawling along the leaves contacts a hair, the trap closes if a different hair is contacted within twenty seconds of the first strike. The requirement of redundant triggering in this mechanism serves as a safeguard against a waste of energy in trapping objects with no nutritional value. Dionaea is a monotypic genus closely related to the waterwheel plant and sundews, all of which belong to the family Droseraceae. Description: The Venus flytrap is a small plant whose structure can be described as a rosette of four to seven leaves, which arise from a short subterranean stem that is actually a bulb-like object. Each stem reaches a maximum size of about
three to ten centimeters, depending on the time of year, longer leaves with robust traps are usually formed after flowering. Flytraps that have more than 7 leaves are colonies formed by rosettes that have divided beneath the ground. Illustration from Curtis's Botanical Magazine byWilliam Curtis (1746–1799) The leaf blade is divided into two regions: a flat, heart-shaped photosynthesis-capable petiole, and a pair of terminal lobes hinged at the midrib, forming the trap which is the true leaf. The upper surface of these lobes contains red anthocyanin pigments and its edges secrete mucilage. The lobes exhibit rapid plant movements, snapping shut when stimulated by prey. The trapping mechanism is tripped when prey contacts one of the three hair-like trichomes that are found on the upper surface of each of the lobes. The trapping mechanism is so specialized that it can distinguish between living prey and non-prey stimuli such as falling raindrops; two trigger hairs must be touched in succession within 20 seconds of each other or one hair touched twice in rapid succession, whereupon the lobes of the trap will snap shut in about one-tenth of a second. The edges of the lobes are fringed by stiff hair-like protrusions or cilia, which mesh together and prevent large prey from escaping. (These protrusions, and the trigger hairs, also known as sensitive hairs, are probablyhomologous with the tentacles found in this plant’s close relatives, the sundews.) Scientists have concluded that the Venus flytrap is closely related to Drosera (sundews), and that the snap trap evolved
from a fly-paper trap similar to that of Drosera. The holes in the meshwork allow small prey to escape, presumably because the benefit that would be obtained from them would be less than the cost of digesting them. If the prey is too small and escapes, the trap will reopen within 12 hours. If the prey moves around in the trap, it tightens and digestion begins more quickly. Speed of closing can vary depending on the amount of humidity, light, size of prey, and general growing conditions. The speed with which traps close can be used as an indicator of a plant's general health. Venus flytraps are not as humidity-dependent as are some other carnivorous plants, such as Nepenthes, Cephalotus, most Heliamphora, and some Drosera. The Venus flytrap exhibits variations in petiole shape and length and whether the leaf lies flat on the ground or extends up at an angle of about 40–60 degrees. The four major forms are: 'typica', the most common, with broad decumbent petioles; 'erecta', with leaves at a 45-degree angle; 'linearis', with narrow petioles and leaves at 45 degrees; and 'filiformis', with extremely narrow or linear petioles. Except for 'filiformis', all of these can be stages in leaf production of any plant depending on season (decumbent in summer versus short versus semi-erect in spring), length of photoperiod (long petioles in spring versus short in summer), and intensity of light (wide petioles in low light intensity versus narrow in brighter light). When grown from seed, plants take around four to five years to reach maturity and will live for 20 to 30 years if cultivated in the right conditions. Courtesy: http://en.wikipedia.org/wiki/Venus_flytrap, Open images in browser to find its source of sharing.
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The Legend of Man eating tree of Madagaskar


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In 1881 a magazine called the South Australian Register ran a story by a traveler called Carle Liche. He tells us that while travelling through Madagascar, he was horrified to watch the native Mdoko tribe sacrifice a woman to a man-eating tree. He stated that the , a young girls is forced to drink the liquid from the tree. Then she is compelled to get up into the middle of the tree. The leaves raise slowly and completely hide the girl. The tree's tendrils took the woman by the neck and strangled her, before apparently engulfing the body. As her screams fade, the leaves rise until she is visible no more. Upon returning to the site ten days later, Liche finds nothing but a grinning skull within the plants’ now-lowered leaves. The story of the Man-Eating Tree of Madagascar is one of the great tall tales of the colonial era. It first appeared in the South Australian Registar, apparently having been written by Liche himself. It was repeated in several books thereafter. In central America, reports of a similar tree called the Ya-Te-Veo appeared around 1887.In his 1924 book "Madagascar, land of the man-eating tree" former Michigan Governor Chase Osborn recounted Liche's tale, and mentioned that missionaries and locals in Madagascar all knew of the deadly tree. The tree, is described as similar to a colossal pineapple. It is about eight feet tall and six feet around the base. It has long tendrils, which reach upward, each about as thick as the arm of a man. The leaves are large and concave, and are lined with "claws". From the tree comes an intoxicating liquid, which the natives drink.Tribes seem to worship it, giving it young girls as sacrifice. It is said to take the lives of young girls rather than men. When the sacrifice begins, a young girls is forced to drink the liquid from the tree. Then she is compelled to get up into the middle of the tree. The leaves raise slowly and completely hide the girl. The pressure of the tendrils and leaves is like a vise and it is said the body of the girl is crushed. Only the bones of the victim are found. Unfortunately, Liche's accounts may have been an exaggeration, as both the Mdoko tribe nor the man-eating tree have ever been found anywhere on the island of Madagascar. Researchers who investigated this case in the 20th century found no evidence to prove Liche’s story . They guessed that the idea of man-eating plants might have come from carnivorous plant or "meat-eating" trees that rather trap animals, mostly insects, and take the nutrients out of the unfortunate victim's body. As Madagascar is at this time a still heavily-forested country that remains alien to outsiders and most of its part is still kept under the wraps. So, we can hope in near future we will come to know about the reality behind this fact. Source: Article
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Top 9 Most Dangerous Birds

When you think about birds, you probably think of small, cute animals flying through the air, swooping down to reach their nest. Maybe you think of those “pretty” song birds in the morning. I, personally find them annoying. In any case, the image of a bird generally doesn’t produce anything terrifying. However, not all birds are cute, and not all of them are nice, so to speak. There are hundreds of birds that could attack a human, and do a lot of damage. Here is a list of nine most dangerous bird.

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1. Cassowaries Cassowaries, an endangered species, are large, flightless birds that live in the rainforests, woodlands and swamps of Australia. Cassowaries are unpredictable, aggressive and are known to kick up their large, clawed feet. Their kicks are capable of breaking bones, and their claws have been likened to daggers.

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2. Ostriches:  Ostriches are suspicious, skittish and can be dangerous. They're the largest living bird (they can reach over 9 feet tall and 350 pounds) and they can outrun you (a steady 30 miles an hour for 10 miles straight). Like the cassowary, they have strong legs (their kick can kill a hyena) and sharp claws.

3. Canada Geese: Canada geese are very aggressive and, particularly if you (purposely or inadvertently) come near their nests or young, they may chase you away and even bite you.

4. Seagulls: Seagulls are extremely aggressive and are known to attack and even peck at people's heads to protect their nests and young. In fact, in Britain people have been forced to carry umbrellas to avoid the attacks, at least one woman was taken to an emergency room with deep beak wounds to her head, and a pet dog was killed by the birds.

5. Owls: Owls are raptors, or birds of prey, and they use their talons and beaks to kill and eat their catch. In a closed space, or if the bird was scared or agitated, it could cause serious harm to you. 

Hawk And Falcon
6. Hawks and Falcons: Also birds of prey, the sharp talons and beaks that hawks and falcons use to hunt, along with their quick speed and agility, pose serious dangers to humans, even if the birds are just babies (falcons' beaks are also specially configured to cut through the spinal cords of their prey).

7. Eagles:  Eagles are strong (strong enough to carry away something that weighs four pounds), aggressive birds, and although they don't pose much of a danger to humans in the wild, in a closed space their beak and talons could easily harm a human. (FYI, they can eat about a pound of fish in just four minutes.)

8. Vultures:  If cornered, a vulture (many species of which are now endangered) may hiss or make a low grunting sound at you. They, of course, also have sharp, hooked beaks that can tear meat, along with excellent eyesight.

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9. Rheas: The rhea, native to South America, is a large, flightless bird that can grow to be 60-80 pounds. Though smaller than ostriches and not as aggressive as cassowaries, rheas have heavily muscled legs, hard spurs on their feet and their kicks can bring a force of 800 pounds per square inch. Source: Article
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Tendulkar bats for green energy

Gurgaon, July 26, (IANS) Legendary batsman Sachin Tendulkar Friday advised his fans not to waste natural resources and double up efforts to save the environment. Tendulkar was in the city to launch Toshiba's environment conservation initiative 'Bat for the Planet'. "We should save our natural resources by taking small steps on our behalf because the change cannot happen overnight. As we keep ourselves healthy, we should keep our earth healthy. In the dressing room after a good performance on the field, we are asked to double up the good performance likewise we should double up our efforts to save environment," Tendulkar said. The master blaster distributed prizes to the winners of a painting competition, which had a theme based on various environmental issues, for children from 40 different schools. "The kids are very creative and aware of the energy problem. We will raise money for under privileged children by auctioning the painting," Tendulkar said. Source: News Track India, Image: flickr.com
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