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Malaria came from gorillas Western Lowland Gorillas are seen in a forest clearing called a bai in the northern Republic of Congo. Malaria may have spread globally from a single gorilla to a single human. Prof Yash
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Universe Trends |
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Malaria came from gorillas Malaria appears to have jumped to humans from gorillas, and the parasite may have spread globally from a single gorilla to a single human, according to researchers. DNA from the droppings of nearly 3,000 apes—gorillas, chimpanzees and bonobos—shows the strain of malaria parasite most common in humans is virtually identical to one of many strains that infects gorillas. It is far more distant than strains affecting chimps and their close cousins, the bonobos, Beatrice Hahn of the University of Alabama at Birmingham and colleagues reported. Hahn and colleagues used ape droppings collected to study the origins of the AIDS virus for their study, published in the journal Nature. “We had them all nicely organised, genetically characterised in our freezer,” Hahn said in a telephone interview. Hahn’s team tested genetic material from the human immunodeficiency virus for their AIDS studies and took a similar approach for the latest work, looking for DNA from malaria parasites, including the Plasmodium falciparum parasite that causes most human cases. “Wild apes, in particular the common chimps and the western gorillas, are naturally infected with at least eight or nine different Plasmodium species,” Hahn said. For years chimps were the chief suspects. But Hahn’s data shows that gorillas, and only gorillas, are infected by a Plasmodium species virtually identical on the genetic level to the type that infects humans. “Now, how many mosquitoes were biting however many humans or gorillas I do not know,” Hahn said. “But the end result is, based on sequence analysis of 105 human Plasmodium parasites, it looks like there was a single transmission.” In other words, the parasite only had to infect one person or a small group of people before quickly taking hold and spreading to much of the world. Malaria, which kills an estimated 8,00,000 people a year according to the World Health Organization, is spread when a mosquito feeds on an infected person and carries the parasite to another human. There is no cure and no vaccine, although drugs can control the infection and help prevent the spread. The findings could eventually have implications for efforts to get rid of malaria, said Dr. Larry Slutsker, who heads the malaria program at the U.S. Centers for Disease Control and Prevention. “If we were trying to eradicate, meaning we were trying to rid the planet of every last parasite and there was a reservoir in western gorillas, that would have implications for eradication. I don’t think we are there, obviously,” he said. Gorillas, or the areas where they live, would likely have to be included in any such program so the parasite could not once again move into people. Slutsker said the parasite may not necessarily have spread to people from apes via a mosquito. It can also be spread by direct blood transfer—perhaps while a gorilla was being butchered for food. Many experts believe this is how HIV first spread to humans. What the researchers cannot say is when this happened. HIV mutates—evolves—quickly and these changes can be used as what is known as a molecular clock to date changes. Malaria parasites change much more slowly, Edward Holmes of Pennsylvania State University wrote in a commentary on the Nature study. Many human diseases come from animals, including influenza, plague and West Nile virus.
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Universe What is a solar tsunami? How does it damage transformers and
transmission lines? The Sun is a very active body. Active in the sense that besides hot gases with their heat and light that we sense on the earth even sitting on the ground very large electromagnetic phenomena define its surface life. Lot of material on the surface is ionized and there are lot of magnetic fields and plasma clouds whirling around. Besides the convective and radiative energy coming from the thermonuclear furnace inside, the fact that the sun rotates produces tangling movements of plasma and winding up magnetic fields. Energy locked up in magnetic fields gets released on occasion. All this also produces emission of charged particles from the surface of the sun. Often there are solar flares rising up to great height. In some violent activities lot of coronal mass is thrown out at great speed. Continuous emission of charged particles is called the solar wind, which really plasma streaming out, carrying with it the locked in magnetic fields. This solar wind does travel towards the earth. However the earth is mostly protected from its impact because of its magnetic field. However close to magnetic poles this protection is not available because in these regions the field direction is almost parallel to the direction from which the charged particles come. There fore they do enter the earth atmosphere and that is seen in spectacular phenomena of Aurora, which nothing but the light emitted by the ionised nitrogen and oxygen of air. Coming now to the specific question you have asked, the solar wind is not a uniform, well-behaved wind. There are occasion on which explosions occur on the surface of the sun and a lot of coronal mass is injected into the wind. Occasionally, this is at great speed and its impact on the earth is felt in strong disturbances of magnetic field of the earth. This produces large electromagnetic events in which electrical circuits and transmission lines can be severely affected, particularly in Polar Regions. In that sense the happening can be considered to have the nature of a tsunami though, in my view, the description is more colourful than completely analogous. If a body is sent into the solar system, keeping it far from heavy bodies like planets, moons etc., then will it start orbiting the sun? If yes, then how can just the gravitational pull of the sun impart an orbital motion to it? Just think that the body you sent up is the earth itself. If that body had enough momentum to go near the sun and had a reasonable translational velocity it can orbit the sun. But think of a ball you throw up while playing cricket. It already has the right velocity and momentum to orbit the sun. Indeed it is already doing that along with the whole earth. Another way of understanding this is to think of a large number of asteroids, of all sizes that orbit the sun in slightly different orbits. Many meteors that come from far away do end up orbiting the sun though often in orbits not easily observed with naked eye. You must have heard of the Halley’s comet that goes around the sun once in about 70 years - and it has been doing that for thousands of years if not much longer. Sun has its influence up to very large distances. Perhaps you are wondering whether we could put our own satellites around the sun. Of course we can, though the easiest way is to make them satellites of the earth and let the earth carry them around the sun on the back of the earth itself. |
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Trends OSLO Flowers picked up to 150 years ago in Victorian England show that old collections of pressed plants around the world can help the study of climate change, scientists said on Wednesday. Ecologists compared samples of early spider orchids, held in collections with notes showing the exact day in spring when they were picked in southern England from 1848-1958, and dates when the same flower blossomed in the wild from 1975-2006.
Wind could have parted Red Sea for Moses WASHINGTON Moses might not have parted the Red Sea, but a strong east wind that blew through the night could have pushed the waters back in the way described in biblical writings and the Koran, U.S. researchers reported on Tuesday. Computer simulations, part of a larger study on how winds affect water, show wind could push water back at a point where a river bent to merge with a coastal lagoon, the team at the National Center for Atmospheric Research and the University of Colorado at Boulder said.
New elephant shrew species maybe found in Kenya NAIROBI Researchers may have discovered a previously unknown species of the giant elephant shrew—a small mammal with a nose like a trunk—in a remote Kenyan forest. They said Tuesday they captured images of the rat-sized animal on camera-traps in the Boni-Dodori forest along Kenya’s northeastern coast while they were researching biodiversity. |
Malaria appears to have jumped to humans from gorillas, and the parasite may have spread globally from a single gorilla to a single human, according to researchers.
DNA from the droppings of nearly 3,000 apes—gorillas, chimpanzees and bonobos—shows the strain of malaria parasite most common in humans is virtually identical to one of many strains that infects gorillas.
