Oldest primitive animal fossil found in China
Beijing: Scientists have discovered the world’s oldest primitive animal fossil in China, suggesting that animals have been on Earth for at least 600 million years.
A new study described a well-preserved, rice grain-sized primitive sponge fossil recovered from 600-million-year old rocks in southwest China’s Guizhou Province.
The prior oldest known primitive sponge fossil only dated to 530 million years ago, in early Cambrian period. “It’s the world’s earliest and most credible fossil record of primitive animal bodies,” said lead author Maoyan Zhu of the Nanjing Institute of Geology and Palaeontology, which is part of Chinese Academy of Sciences.
“The discovery will help remove doubts as to whether animals have emerged on Earth 600 million years ago,” said Zhu.
An analysis found that the fossilised animal, slightly more than 1.2 mm wide and 1.1 mm tall, displays multiple independent characters of modern adult sponges, Xinhua News agency reported.
The analysis was based on advanced imaging techniques including scanning electron microscope and synchrotron X-ray tomography.
Researchers said the specimen is composed of hundreds of thousands of cells, and has a gross structure consisting of three adjacent hollow tubes sharing a common base.
“These features showed it’s a primitive animal very similar to modern sponges and could have lived a filter-feeding life through its simple water canal system on the shallow sea floor,” Zhu added.
Sponges are the most primitive living animals. They have only differentiated cells, but no real organs or tissues. The study was published in the journal PNAS. (PTI)
‘You could be a descendant of Genghis Khan’
London: Millions of modern Asian men have descended from 11 powerful dynastic leaders who lived up to 4,000 years ago – including Mongolian warlord Genghis Khan, a new study has found.
Geneticists from the University of Leicester examined the male-specific Y chromosome, which is passed from father to son, in more than 5,000 Asian men belonging to 127 populations.
Most Y-chromosome types are very rare, but the team discovered 11 types that were relatively common across the sample and studied their distributions and histories.
Two common male lineages have been discovered before, and have been ascribed to one well-known historical figure, Genghis Khan, and another less-known one, Giocangga.
The Leicester team found genetic links via a chain of male ancestors to both Genghis Khan and Giocangga, in addition to nine other dynastic leaders who originated from throughout Asia and date back to between 2100 BC and 700 AD. “The youngest lineages, originating in the last 1700 years, are found in pastoral nomadic populations, who were highly mobile horse-riders and could spread their Y chromosomes far and wide,” the project’s leader, Professor Mark Jobling from Leicester’s Department of Genetics, said. “For these lineages to become so common, their powerful founders needed to have many sons by many women, and to pass their status – as well as their Y chromosomes – on to them. The sons, in turn, could then have many sons, too. It’s a kind of trans-generation amplification effect,” said Jobling.
“Identifying the ancestors responsible for these lineages will be difficult or impossible, as it would rely on finding their remains and extracting and analysing ancient DNA,” first author of the study, Patricia Balaresque, now at Universite Paul Sabatier in Toulouse, said. “This hasn’t yet been done for Genghis Khan, for example, so the evidence remains circumstantial, if pretty convincing,” Balaresque added.
The study was published in the journal European Journal of Human Genetics. (PTI)
Teacher sacked for letting students get drunk
London: A female teacher in Britian has been sacked for allegedly letting underage students of a boarding school get drunk on a supervised trip to an Indian restaurant.
Deana Hall, 53, claims she was made a scapegoat, and was unfairly dismissed from her job following the incident in Lancashire, north-west England.
The students and three staff members from Moorland High School in the town of Clitheroe drank wine, lager and spirits as they enjoyed Indian food at Balti Stan restaurant at Clayton-le-Moors.
“She still can’t accept that she did anything wrong and I think it’s appalling,” head teacher Jonathan Harrison said in evidence during an employment tribunal hearing this week. “She brought the school into disrepute. She was in breach of the trust of the school and the parents and her conduct could have led to a serious injury to a student who, under the influence of alcohol, could have wandered out of the restaurant and into the path of a car which could have closed the school down. “I find it impossible that she has not accepted any wrong doing.” The hearing was shown a series of pictures allegedly showing students with alcohol and heard that one boy drank a glass of wine and three pints of lager, and that he bought a Jack Daniels with Coke for another student. Hall said it was the responsibility of her superior, boarding house manager, Deborah Richards, to secure the correct permissions. Following the incident on May 16, 2014, Richards resigned her position and told the head teacher that she accepted full responsibility.
“Mrs Richards rang me up afterwards and told me that she felt awful that we were going to lose our jobs because she had not done her job correctly,” Hall told the tribunal in her claim of “unfair dismissal”.
“No student was drunk at all and we made sure of that at the end of the night. “I would not have permitted alcohol at all if I had organised the trip but my boss said that it was ok and I had no reason not to trust her,” she said. The judgement in the case has been reserved by Judge Rebecca Howard and is expected to be given in the next four weeks. (PTI)
