Cow may be biggest mammal if humans keep up extinctions: Study

Agencies
May 12, 2018

Oslo, May 12: The spread of humans around the world from Africa thousands of years ago wiped out big mammals in a shrinking trend that could make the cow the biggest mammal on Earth in a few centuries` time, a scientific study said on Thursday.

The spread of hominims - early humans and relatives such as Neanderthals - from Africa coincided with the extinction of mammals such as the mammoths, sabre-toothed tiger and glyptodon, an armadillo-like creature the size of a car.

"There is a very clear pattern of size-biased extinction that follows the migration of hominims out of Africa," lead author Felisa Smith of the University of New Mexico told Reuters of the study published in the journal Science.

Humans apparently targeted big species for meat, while smaller creatures such as rodents escaped, according to the report examining trends over 125,000 years.

In North America, for instance, the mean body mass of land-based mammals has shrunk to 7.6 kg (17 lbs) from 98.0 after humans arrived.

If the trend continues "the largest mammal on Earth in a few hundred years may well be a domestic cow at about 900 kg" (2,000 lbs), the U.S. team wrote.

That would mean the loss of creatures including elephants, giraffes and hippos. In March, the world`s last male northern white rhino died in Kenya.

But other research casts doubt on a continued shrinking of mammals, partly because of conservation efforts to stave off threats to wildlife such as climate change, loss of forest habitats and pollution and expanding cities.

Thomas Brooks, chief scientist of the International Union for Conservation of Nature (IUCN) who was not involved in the study, said the projection of ever smaller mammals was "doom and gloom."

"Happily I don`t think it`s very likely," he told Reuters, saying that other research suggests that large animals such as elephants are more likely to benefit in protected areas than smaller ones.

And a Red List of threatened species, maintained by the IUCN, also lists some wild mammals roughly the size of a cow - such as the African buffalo or the brown bear - as unendangered.

The Science study also excludes marine mammals such as the blue whale, the largest creature that has ever existed. It is endangered on the Red List but the populations are rising after a moratorium on hunts.

Smith said that "my optimist hat would like to say that it`s not going to happen because we love elephants`." But she said populations of large land mammals were falling and "declining population is the trajectory to extinction."

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Agencies
June 13,2020

The Brazilian government said that the Amazon rainforest witnessed deforestation of a record 829 sq km in May, the highest monthly level since 2015.

On Friday, the National Institute for Space Research (INPE) said that deforestation in the Amazon increased by 91 sq km compared to the same period last year, reports Xinhua news agency.

Between January and April, destruction of the forest by illegal loggers and ranchers rose 55 per cent, or a total of 1,202 sq km was wiped out, it said.

The Real-time Deforestation Detection system, a federal project created to monitor human activity in the Amazon, alerted authorities to the increase in the rate of destruction of the rainforest.

A recent study by the Amazon Environmental Research Institute (IPAM) warned that deforestation in 2020 could reach 11,900 sq km if the pace of May, June, and July follows the historical average.

Deforestation in the region has soared since President Jair Bolsonaro took office last year, according to conservation groups.

He has argued that more farming and mining in protected areas of the forest were the only way to lift the region out of poverty.

Bolsonaro's environmental policies have been widely condemned but he has rejected the criticism, saying Brazil remains an example for conservation.

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Agencies
May 12,2020

New Delhi, May 13: Prime Minister Narendra on Tuesday announced Rs 20 lakh crore special economic package for the country to be 'self-reliant' and deal with COVID-19.

"I announce a special economic package today. This will play an important role in the 'Atmanirbhar Bharat Abhiyan.' The announcements made by the government over COVID, decisions of RBI and today's package totals to Rs 20 lakh crore. This is 10 per cent of India's GDP," said Prime Minister Modi in his address to the nation. The Prime Minister said that humanity would not accept defeat from the coronavirus but the people have to stay safe and move forward.

"We had never seen or heard about such a crisis ever before. This is definitely unimaginable for mankind. It is unprecedented. But humanity will not accept defeat from this virus. We have to not only protect ourselves but also move forward," he said.

Talking about the gravity of the virus, Modi said: "It has been four months the world is fighting COVID-19. More than 42 lakh people from different countries have been infected by COVID-19. More than 2.75 lakh people have lost their lives due to the virus. In India too many families have lost their dear ones, I express my condolences to them."

"Today when the entire world is in crisis, we will have to further firm our resolve," he added.

The Prime Minister on Monday held a video conference meeting with Chief Ministers of all states to discuss the road ahead in India's fight against COVID-19 and noted that he was of the firm view that measures needed during the third phase of lockdown will not be needed in the fourth phase.

Prime Minister Modi had said the need was to reduce the transmission rate of the disease and to increase public activity gradually while adhering to all the guidelines and efforts to be made towards achieving both these objectives.

The phase three of the lockdown is coming to an end on May 17.

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News Network
April 28,2020

Los Angeles, Apr 28: People who experience loss of smell as one of the COVID-19 symptoms are likely to have a mild to moderate clinical course of the disease, according to a study which may help health care providers determine which patients require hospitalisation.

The findings, published in the journal International Forum of Allergy & Rhinology, follows an earlier study that validated the loss of smell and taste as indicators of infection with the novel coronavirus, SARS-CoV-2.

According to the scientists from the University of California (UC) San Diego Health in the US, patients who reported loss of smell were 10 times less likely to be hospitalised for COVID-19 compared to those without the symptom.

"One of the immediate challenges for health care providers is to determine how to best treat persons infected by the novel coronavirus," said Carol Yan, first author of the current study and rhinologist from the UC San Diego Health.

"If they display no or mild symptoms, can they return home to self-quarantine or will they likely require hospitalisation? These are crucial questions for hospitals trying to efficiently and effectively allocate finite medical resources," Yan said.

The findings, according to the researchers, suggest that loss of smell may be predictive of a milder clinical course of COVID-19.

"What's notable in the new findings is that it appears that loss of smell may be a predictor that a SARS-CoV-2 infection will not be as severe, and less likely to require hospitalisation," Yan said.

"If an infected person loses that sense, it seems more likely they will experience milder symptoms, barring other underlying risk factors," she added.

Risk factors for COVID-19 previously reported by other studies include age, and underlying medical conditions, such as chronic lung disease, serious heart conditions, diabetes, and obesity.

In the current study, the scientists made a retrospective analysis between March 3 and April 8 including 169 patients who tested positive for COVID-19 at UC San Diego Health.

They assessed olfactory and gustatory data for 128 of the 169 patients, 26 of whom required hospitalisation.

According to the researchers, patients who were hospitalised for COVID-19 treatment were significantly less likely to report anosmia or loss of smell -- 26.9 per cent compared to 66.7 per cent for COVID-19-infected persons treated as outpatients.

Similar percentages were found for loss of taste, known as dysgeusia, they said.

"Patients who reported loss of smell were 10 times less likely to be admitted for COVID-19 compared to those without loss of smell," said study co-author Adam S. DeConde.

"Moreover, anosmia was not associated with any other measures typically related to the decision to admit, suggesting that it's truly an independent factor and may serve as a marker for milder manifestations of Covid-19," DeConde said.

The researchers suspect that the findings hint at some of the physiological characteristics of the infection.

"The site and dosage of the initial viral burden, along with the effectiveness of the host immune response, are all potentially important variables in determining the spread of the virus within a person and, ultimately, the clinical course of the infection," DeConde said.

If the SARS-CoV-2 virus initially concentrates in the nose and upper airway, where it impacts olfactory function, that may result in an infection that is less severe and sudden in onset, decreasing the risk of overwhelming the host immune response, respiratory failure, and hospitalisation, the scientists added.

"This is a hypothesis, but it's also similar to the concept underlying live vaccinations," DeConde explained.

"At low dosage and at a distant site of inoculation, the host can generate an immune response without severe infection," he added.

Loss of smell, according to the study, might also indicate a robust immune response which has been localised to the nasal passages, limiting effects elsewhere in the body.

Citing the limitations of the study, the scientists said they relied upon self-reporting of anosmia from participants, which posed a greater chance of recall bias among patients once they had been diagnosed with COVID-19.

They added that patients with more severe respiratory disease requiring hospitalisation may not be as likely to recognise or recall the loss of smell.

So the researchers said more expansive studies are needed for validating the results.

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