Dinosaurs shrank to birds in order to survive

May 7, 2014

Dinosaurs_shrankLondon, May 7: Dinosaurs are alive and here! Although most dinosaurs went extinct 65 million years ago, one dinosaur lineage survived and lives on today as a major evolutionary success story - the birds, according to a new Oxford study.

The study that'weighed' hundreds of dinosaurs suggests shrinking their bodies may have helped the group that became birds to continue exploiting new ecological niches throughout their evolution, and become hugely successful today.

An international team, led by scientists at Oxford University and the Royal Ontario Museum, estimated the body mass of 426 dinosaur species based on the thickness of their leg bones.

The team found that dinosaurs showed rapid rates of body size evolution shortly after their origins, around 220 million years ago.

However, these soon slowed: only the evolutionary line leading to birds continued to change size at this rate, and continued to do so for 170 million years, producing new ecological diversity not seen in other dinosaurs.

"Dinosaurs aren't extinct; there are about 10,000 species alive today in the form of birds. We wanted to understand the evolutionary links between this exceptional living group, and their Mesozoic relatives, including well-known extinct species like T rex, Triceratops, and Stegosaurus," said Dr Roger Benson of Oxford's Department of Earth Sciences.

"We found exceptional body mass variation in the dinosaur line leading to birds, especially in the feathered dinosaurs called maniraptorans. These include Jurassic Park's Velociraptor, birds, and a huge range of other forms, weighing anything from 15 grams to 3 tonnes, and eating meat, plants, and more omnivorous diets," said Benson, who led the study.

The team believes that small body size might have been key to maintaining evolutionary potential in birds, which broke the lower body size limit of around 1 kilogramme seen in other dinosaurs.

They examined rates of body size evolution on the entire family tree of dinosaurs, sampled throughout their first 160 million years on Earth.

"What we found was striking. Dinosaur body size evolved very rapidly in early forms, likely associated with the invasion of new ecological niches. In general, rates slowed down as these lineages continued to diversify," said Dr David Evans at the Royal Ontario Museum, who co-devised the project.

"But it's the sustained high rates of evolution in the feathered maniraptoran dinosaur lineage that led to birds - second great evolutionary radiation of dinosaurs," said Evans.

The evolutionary line leading to birds kept experimenting with different, often radically smaller, body sizes - enabling new body 'designs' and adaptations to arise more rapidly than among larger dinosaurs.

Other dinosaur groups failed to do this, got locked in to narrow ecological niches, and ultimately went extinct.

The research was published in the journal PLOS Biology.

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Agencies
January 3,2020

Giving each and every app access to personal information stored on Android smartphones such as your contacts, call history, SMS and photos may put you in trouble as bad actors can easily use these access to spy on you, send spam messages and make calls anywhere at your expense or even sign you up for a premium "service", researchers from cybersecurity firm Kaspersky have warned.

But one can restrict access to such information as Android lets you configure app permissions. 

Giving an app any of these permissions generally means that from now on it can obtain information of this type and upload it to the Cloud without asking your explicit consent for whatever it intends to do with your data.

Therefore, security researchers recommend one should think twice before granting permissions to apps, especially if they are not needed for the app to work. 

For example, most games have no need to access your contacts or camera, messengers do not really need to know your location, and some trendy filter for the camera can probably survive without your call history, Kaspersky said. 

While decision to give permission is yours, the fewer access you hand out, the more intact your data will be.

Here's what you should know to protect your data.

SMS: An app with permission to send and receive SMS, MMS, and WAP (Wireless Application Protocol) push messages, as well as view messages in the smartphone memory will be able to read all of your SMS correspondence, including messages with one-time codes for online banking and confirming transactions.

Using this permission, the app can also send spam messages in your name (and at your expense) to all your friends. Or sign you up for a premium "service." You can see and conrol which apps have these rights by going to the settings of your phone.

Calendar: With permission to view, delete, modify, and add events in the calendar, prying eyes can find out what you have done and what you are doing today and in the future. Spyware loves this permission.

Camera: Permission to access the camera is necessary for the app to take photos and record video. But apps with this permission can take a photo or record a video at any moment and without warning. Attackers armed with embarrassing images and other dirt on you can make life a misery, according to Kaspersky.

Contacts: With permission to read, change, and add contacts in your address book, and access the list of accounts registered in the smartphone, an app can send your entire address book to its server. Even legitimate services have been found to abuse this permission, never mind scammers and spammers, for whom it is a windfall.

This permission also grants access to the list of app accounts on the device, including Google, Facebook, and many other services.

Phone: Giving access to your phone means permission to view and modify call history, obtain your phone number, cellular network data, and the status of outgoing calls, add voicemail, access IP telephony services, view numbers being called with the ability to end the call or redirect it to another number and call any number.

This permission basically lets the app do anything it likes with voice communication. It can find out who you called and when or prevent you from making calls (to a particular number or in general) by constantly terminating calls. 

It can eavesdrop on your conversations or, of course, make calls anywhere at your expense, including to pay-through-the-nose numbers, Kaspersky warned.

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Agencies
June 19,2020

Denser places, assumed by many to be more conducive to the spread of the coronavirus that causes COVID-19, are not linked to higher infection rates, say researchers.

The study, led by Johns Hopkins University, published in the Journal of the American Planning Association, also found that dense areas were associated with lower COVID-19 death rates.

"These findings suggest that urban planners should continue to practice and advocate for compact places rather than sprawling ones, due to the myriad well-established benefits of the former, including health benefits," says study lead author Shima Hamidi from Johns Hopkins Bloomberg School of Public Health in the US.

For their analysis, the researchers examined SARS-CoV-2 infection rates and COVID-19 death rates in 913 metropolitan counties in the US.

When other factors such as race and education were taken into account, the authors found that county density was not significantly associated with county infection rate.

The findings also showed that denser counties, as compared to more sprawling ones, tended to have lower death rates--possibly because they enjoyed a higher level of development including better health care systems.

On the other hand, the research found that higher coronavirus infection and COVID-19 mortality rates in counties are more related to the larger context of metropolitan size in which counties are located.

Large metropolitan areas with a higher number of counties tightly linked together through economic, social, and commuting relationships are the most vulnerable to the pandemic outbreaks.

According to the researchers, recent polls suggest that many US citizens now consider an exodus from big cities likely, possibly due to the belief that more density equals more infection risk.

Some government officials have posited that urban density is linked to the transmissibility of the virus.

"The fact that density is unrelated to confirmed virus infection rates and inversely related to confirmed COVID-19 death rates is important, unexpected, and profound," said Hamidi.

"It counters a narrative that, absent data and analysis, would challenge the foundation of modern cities and could lead to a population shift from urban centres to suburban and exurban areas," Hamidi added.

The analysis found that after controlling for factors such as metropolitan size, education, race, and age, doubling the activity density was associated with an 11.3 per cent lower death rate.

The authors said that this is possibly due to faster and more widespread adoption of social distancing practices and better quality of health care in areas of denser population.

The researchers concluded that a higher county population, a higher proportion of people age 60 and up, a lower proportion of college-educated people, and a higher proportion of African Americans were all associated with a greater infection rate and mortality rate.

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Agencies
June 12,2020

Mumbai, Jun 12: Following an overwhelming response for the mega rights issue of Mukesh Ambani-owned Reliance Industries, the partly paid-up rights shares are set to debut on stock exchanges on June 15.

The biggest ever Rs 53,124 crore rights issue was subscribed 1.59 times and received bids worth Rs 84,000 crore on June 3.

Reliance said the rights issue saw a huge investor interest, including from lakhs of small investors and thousands of institutional investors, both Indian and foreign.

In 2019, Ambani said in the Reliance's annual general meeting that the company will be net zero debt by March 2021. The company is on course to achieve its target ahead of the deadline.

"In spite of the COVID-19 crisis and the lockdowns, the due-diligence by Saudi Aramco for the planned investment in the O2C business is on track as both the parties are committed and actively engaged," he said recently.

"With a strong visibility to these equity infusions, Reliance is set to achieve net zero debt status ahead of its own aggressive timeline. We believe rights issue was a part of the company's strategy of deleveraging its balance sheet," said Ambani. 

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