Wolf-sized otters roamed Earth over 6 million years ago

January 25, 2017

Washington, Jan 25: Prehistoric otters may have been of the size of a modern wolf, say scientists who have discovered 6.24 million-year-old fossils of one of the largest otter species known to science. Remains of the large extinct otter, which had large, powerful jaws and is estimated to have weighed about 50 kilogrammes, was found in the northeastern Yunnan Province in China.

Wolf

The species, named Siamogale melilutra, belongs to an ancient lineage of extinct otters that was previously known only from isolated teeth from a different, much older species that was recovered in Thailand. Researchers from Cleveland Museum of Natural History in the US recovered a complete cranium, mandible, dentition and various skeletal elements - offering a wealth of insight into the taxonomy, evolutionary history and functional morphology of this new species.

"While the cranium is incredibly complete, it was flattened during the fossilisation process," said Denise Su, from the Cleveland Museum of Natural History. "The bones were so delicate that we could not physically restore the cranium. Instead, we CT-scanned the specimen and virtually reconstructed it in a computer," said Su.

The CT restoration showed a combination of otter-like and badger-like features, giving way to the species name "melilutra," which combines the Latin names for badger (meles) and otter (lutra). Siamogale melilutra had a large, powerful jaw with the enlarged, bunodont (rounded-cusped) teeth typical of many otter lineages.

This raises the question of whether these bunodont teeth were inherited by all otters from a common ancestor or evolved independently in different otter lineages over time because of the evolution of similar adaptations to thrive in similar environments - a phenomenon called "convergent evolution."

Through their analysis, researchers found that bunodont teeth independently appeared at least three times over the evolutionary history of otters, suggesting convergent evolution to be the cause. The completeness of the specimens from Shuitangba allows the scientists to better understand the evolutionary history of otters and specifically this enigmatic genus from the Miocene, of which there had been little information.

The findings show that Siamogale belongs to one of the oldest and most primitive lineages of the otter family, which goes back at least 18 million years in the form of Paralutra from Europe. The scientists are working to understand other aspects of the life of Siamogale melilutra.

"The discovery of the otter helps solve some questions about otter relationships, but has opened the door to new questions," said Xiaoming Wang from the Natural History Museum of Los Angeles County in the US. The study was published in The Journal of Systematic Paleontology.

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Agencies
February 6,2020

Washington D.C., Feb 6: An international team of astronomers has found an unusual monster galaxy that existed about 12 billion years ago when the universe was only 1.8 billion years old.

The team of astronomers was led by scientists at the University of California, Riverside.

Dubbed XMM-2599, the galaxy formed stars at a high rate and then died. Why it suddenly stopped forming stars is unclear.

"Even before the universe was 2 billion years old, XMM-2599 had already formed a mass of more than 300 billion suns, making it an ultra massive galaxy," said Benjamin Forrest, a postdoctoral researcher in the UC Riverside Department of Physics and Astronomy and the study's lead author.

"More remarkably, we show that XMM-2599 formed most of its stars in a huge frenzy when the universe was less than 1 billion years old and then became inactive by the time the universe was only 1.8 billion years old," Forrest added.

The team used spectroscopic observations from the W. M. Keck Observatory's powerful Multi-Object Spectrograph for Infrared Exploration or MOSFIRE, to make detailed measurements of XMM-2599 and precisely quantify its distance.

The study results appear in the Astrophysical Journal.

"In this epoch, very few galaxies have stopped forming stars, and none are as massive as XMM-2599," said Gillian Wilson, a professor of physics and astronomy at UCR in whose lab Forrest works.

"The mere existence of ultramassive galaxies like XMM-2599 proves quite a challenge to numerical models. Even though such massive galaxies are incredibly rare at this epoch, the models do predict them."

"The predicted galaxies, however, are expected to be actively forming stars. What makes XMM-2599 so interesting, unusual, and surprising is that it is no longer forming stars, perhaps because it stopped getting fuel or its black hole began to turn on. Our results call for changes in how models turn off star formation in early galaxies," the professor stated.

The research team found XMM-2599 formed more than 1,000 solar masses a year in stars at its peak of activity -- an extremely high rate of star formation. In contrast, the Milky Way forms about one new star a year.

"XMM-2599 may be a descendant of a population of highly star-forming dusty galaxies in the very early universe that new infrared telescopes have recently discovered," said Danilo Marchesini, an associate professor of astronomy at Tufts University and a co-author on the study.

"We have caught XMM-2599 in its inactive phase," Wilson said, who led the W. M. Keck Observatory data acquisition
Co-author Michael Cooper, a professor of astronomy at UC Irvine, said this outcome is a strong possibility.

"Perhaps during the following 11.7 billion years of cosmic history, XMM-2599 will become the central member of one of the brightest and most massive clusters of galaxies in the local universe," he said.

"Alternatively, it could continue to exist in isolation. Or we could have a scenario that lies between these two outcomes," he stated.

The study was supported by grants from the National Science Foundation and NASA.

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May 27,2020

Due to impacts of COVID-19, shipments of total mobile phones are forecast to decline 14.6% in 2020, while smartphone shipments will achieve a slightly slower decline of 13.7 % year over year to total 1.3 billion units this year, according to a Gartner forecast on Tuesday.

"While users have increased the use of their mobile phones to communicate with colleagues, work partners, friends and families during lockdowns, reduced disposable income will result in fewer consumers upgrading their phones," Ranjit Atwal, Senior Research Director at Gartner, said in a statement.

"As a result, phone lifetimes will extend from 2.5 years in 2018 to 2.7 years in 2020," said Atwal.

In 2020, affordable 5G phones were expected to be the catalyst to increase phone replacements, but now it is unlikely to be the case.

5G phones are now forecast to represent only 11% of total mobile phone shipments in 2020.

"The delayed delivery of some 5G flagship phones is an ongoing issue," said Annette Zimmermann, Research Vice President at Gartner.

"Moreover, the lack of 5G geographical coverage along with the increasing cost of the 5G phone contract will impact the choice of a 5G phone."

Overall, spending on 5G phones will be impacted in most regions apart from China, where continued investment in 5G infrastructure is expected, allowing providers in China to effectively market 5G phones.

The combined global shipments PCs, tablets and mobile phones are on pace to decline 13.6% in 2020, according to the forecast.

PC shipments are expected to decline 10.5% this year. Shipments of notebooks, tablets and Chromebooks are forecast to decline slower than the PC market overall in 2020.

"The forecasted decline in the PC market in particular could have been much worse," said Atwal.

"However, government lockdowns due to COVID-19 forced businesses and schools to enable millions of people to work from home and increase spending on new notebooks, Chromebooks and tablets for those workers. Education and government establishments also increased spending on those devices to facilitate e-learning."

Gartner said that 48 per cent of employees will likely work remotely at least part of the time after the COVID-19 pandemic, compared to 30 % pre-pandemic.

Overall, the work from home trend will make IT departments shift to more notebooks, tablets and Chrome devices for work.

"This trend combined with businesses required to create flexible business continuity plans will make business notebooks displace desk based PCs through 2021 and 2022," said Atwal.

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March 18,2020

Thiruvananthapuram, Mar 18: To raise awareness about protective measures against coronavirus, Kerala Police released a dance video on the State Police Media Centre's Facebook page promoting the washing of hands, here on Tuesday.

In the video, the police officers were seen dancing to the tunes of Kalakkatha from the Malayalam action-drama thriller Ayyappanum Koshiyum while demonstrating the right technique for washing hands.

The video gained over 27,000 likes and over 2,400 comments and more than 33,000 netizens shared the video.

The video has received a positive response with users congratulating Kerala Police for the initiative.

"Congrats Kerala police media for this kind of initiative," one user commented on Facebook. Another user thanked the police in the comments section saying, "Super super thanks to KL (Kerala) police."

The number of people who have tested positive for the coronavirus in Kerala is 25.

The total number of confirmed COVID-19 cases in India has reached 147, including 122 Indians and 25 foreign nationals, said the Ministry of Health and Family Welfare earlier today.

Globally, the virus has infected more than 184,000 people and killed more than 7500, as per the data available on the World Health Organisation website.

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