The Dhaka Times Desk The last surviving woolly mammoth group on the planet died out in a random and sudden mysterious event. Such information has been published in a new study.
This group of mammoths was isolated from the rest of the world for 6,000 years on Wrangel Island in present-day northern Russia's Siberia. They were previously believed to have become extinct through genetic inbreeding.
Love Dalen, an evolutionary geneticist at the Center for Paleogenetics in Stockholm and senior author of the new study, said in a statement, "We can now confidently reject the idea that mammoths were few in number and went extinct for genetic reasons." Perhaps then some random incident happened, in which they were killed. If that random event had not happened, the mammoth would still be on the planet today.
Roughly 300,000 to 10,000 years ago, woolly mammoths roamed the frigid plains of Europe, Asia, and North America. As the ice melted across the north, their survival food slowly disappeared. Due to which their range of movement was also narrowed.
It was during this period that a small herd of mammoths crossed the ice off the northwest coast of Siberia and began living on Wrangel Island. About 10,000 years ago, when the ice crossing also disappeared, the small group of mammoths became isolated from the mainland population. Mammoths lived alone on the frozen island for another 6 thousand years.
In the new study, researchers used DNA from bones and teeth to analyze the genomes of 21 mammoths to examine the consequences of Wrangel Island. They found that woolly mammoths on the island showed signs of inbreeding and low genetic diversity.
But what ultimately happens to the animals is still somewhat of a mystery, the researchers said. For further investigation they will also look for clues to undiscovered mammoth fossils from the last 300 years on Wrangel Island. They believe that their findings are very useful for understanding the ongoing diversity of crises.
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How to prevent dengue
Dengue is a mosquito-borne viral fever. This fever is different from other viral or bacterial fevers. However, this fever is not contagious in any way. This viral fever can occur alone or in combination with other viruses (chikungunya, yellow fever, Burma forest, flu, respiratory syncytial) and bacteria (pneumococcus).
Dengue fever is divided into two categories depending on the severity of symptoms and fever.
1. Common dengue fever
2. Dengue fever with bleeding.
In the case of common dengue fever, the following symptoms are mainly seen-
1. Sudden high fever lasting 2 to 7 days.
2. Severe headache.
3. Pain behind the eyes.
4. Along with the fever, red rash appears all over the body.
5. Severe pain in whole body as well as back pain.
6. Nausea or vomiting.
7. A rash or red bumps on the skin.
In case of dengue fever with bleeding:
1. Bleeding from nose, mouth or vomiting with high fever within 2 to 48 hours.
2. Fluid accumulation in chest or abdomen along with fever.
If any of these symptoms appear, seek medical attention immediately.
On the other hand
Wait at home for the first 3 days of fever. On the other hand, sponge the whole body with water every now and then. This will reduce the level of fever. Drink enough water and rest. After that, if the fever does not decrease or if it continues to increase after some time, consult a doctor immediately.
Things to do to prevent Dengue:
1. Try to keep the surroundings of the house as clean as possible.
2. If there are flower tubs or broken plastic bottles, can shells, tires or polythene inside the house, clean them quickly and drain the accumulated water from the flower tubs.
3. Spray or fog at least 3 times a week to kill mosquitoes.
4. You can keep mosquito repellent cream with you while going out.
5. After evening, younger and older members of the household should use mosquito nets.
6. Clean up any accumulated rain water, as this is the time when Aedes mosquitoes lay their eggs.
7. On the other hand, you can use mats along with mosquito nets to avoid mosquito infestation.
8. Since Aedes mosquitoes bite during the day, it is important to avoid sleeping with mosquito nets while sleeping during the day. Source: https://dmpnews.org
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