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Female lifespan is longer in wild mammal animals than in humans – Phys.Org

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On average, women live longer than men: About 90% of people reaching 110 years old or more are women. The current record holder is Jeanne Calment, who was 122 years old, when she died in 1997.

Now a new study shows, that even greater differences in lifespan are found in wild mammals. The average female wild mammal lives 18.6 % longer than her male counterpart. In humans the difference is “only” 7.8 %.

The study was conducted by researchers from University of Southern Denmark and University Lyon 1 in collaboration with several international teams. It is published in the Proceedings of the National Academy of Sciences of the United States (PNAS).

Moose, killer whale and sheep

– The greatest differences are found in animals like Common brushtail possum, lion, killer whale, moose, greater kudu and sheep, says Fernando Colchero, associate professor and an expert in biostatistics at Interdisciplinary Centre on Population Dynamics, University of Southern Denmark.

The researchers compiled demographic data for more than 130 wild mammal populations and were able to estimate the average longevity and the rate of increase in the risk of dying as a function of age for both sexes.

The analyzes led to unexpected results. Not only do females generally live longer than males in wild mammals, but the difference in longevity between the sexes, although very variable depending on the population, in the vast majority of cases exceeds the difference observed in human populations.

Lower risk of female mortality during adulthood

– For about half of the mammal populations studied, the increased risk of mortality with age is actually more pronounced in females than in males, Fernando Colchero explains.

These results show that the larger longevity of females than males is most likely due to other factors that affect individuals during their entire adult life.

To reach this conclusion, Colchero and his colleagues calculated the average age at death, as well as the rate at which mortality increases with age.

Is risky male behavior a cause?

There is a common belief that males engage in potentially dangerous sexual competitions and live riskier lives than females, and that this could account for their shorter lifespan.

Contrary to this idea, this study reveals that the intensity of sexual selection does not directly modulate the amplitude of the differences in longevity observed between the sexes.

The results rather suggest that complex interactions between the physiological characteristics specific to each sex and local environmental conditions are at play.

We see many variations in the species studied. For some species, the males actually have the longest lifespan. That said, there is a statistically clear trend and there are a number of plausible explanations, says Dalia Conde, associate professor and an expert in animal conservation, Department of Biology, University of Southern Denmark.

Why do the females live longer?

One explanation is that males often are larger and put more energy in sexual characters such as growing larger horns than females. This requires energy, and if the animals live in a harsh climate, the males may be more vulnerable to these extreme environmental conditions.

One example is bighorn sheep (Ovis canadensis), When these animals live in an environment where resources are consistently available, there are almost no differences in their lifespans. But when they live in harsher environments, where winters are more severe, the males live much shorter lives.

Another explanation is that males produce more androgens (male hormones) than females. Androgens modulate immune performance and when present at high levels, they can impair some aspects of the immune defense, making males more susceptible to infections and diseases.

More information:
https://phys.org/news/2020-03-analysis-nonhuman-female-mammals-longer.html

Provided by University of Southern Denmark

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NASA taps SpaceX for future cargo deliveries to the lunar Gateway – SlashGear

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In an announcement on Friday, NASA revealed the first private American space company to receive a Gateway Logistics Services contract under the Artemis program: SpaceX. Under this new deal, SpaceX will eventually deliver various experiments, supplies, and other cargo to the planned lunar Gateway. The space agency has described this as a ‘significant step forward’ in its Artemis program, which is aiming for a manned return to the Moon by 2024.

Under a Gateway Logistics Services contract, NASA will be able to order missions for as long as 12 years, it explained on Friday. The space agency is working on making the lunar Gateway outpost a reality — it will be a small spaceship that remains in lunar orbit, serving as a living space for astronauts, a space lab for scientific work, and more.

As with the International Space Station today, the future Gateway will require regular shipments of cargo and other goods. SpaceX has worked extensively with NASA over the years to launch cargo deliveries, among other things, and it makes sense that the space agency would continue its work with the private space company.

In a statement, NASA Kennedy Space Center’s Deep Space Logistics manager Mark Wiese said:

This is an exciting new chapter for human exploration. We are bringing the innovative thinking of commercial industry into our supply chain and helping ensure we’re able to support crews preparing for lunar surface expeditions by delivering the supplies they need ahead of time.

At this point in time, NASA says that it is planning supply missions to the Gateway that will involve a cargo spacecraft spending between six and 12 months at the outpost each time. SpaceX plays an important role in NASA’s Artemis program and future Mars ambitions, but it isn’t the only private American space company working with the space agency. Among others, Boeing also has considerable involvement with the Artemis program.

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Astronaut tips to survive lockdown: Talk, teamwork, treats – The Jakarta Post – Jakarta Post

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Stick to a daily routine, stay connected with family and treat yourself occasionally – those are some of the tips German astronauts gave for surviving lockdown during the coronavirus crisis, which they said was much like their time in space.

Thomas Reiter, 61, who was the first German astronaut to perform a spacewalk, recalled during a Skype conversation with other astronauts on Thursday how he had a tight daily routine in space.

“I think it’s important to follow a conscious routine in such a situation … keeping that routine all week,” said Reiter, now retired.

But weekend treats were important to look forward to.

“During the week we picked out the things from the food container that each person liked the most for a Friday or Saturday evening and then had a bit better food,” he said.

Reiter recalled using Skype to connect with his family from the International Space Station. Sitting in front of a bookshelf, he recommended using lockdown to catch up on reading.

“You have to be able to retreat,” he said, but added that in confinement with others, people must put the group first. “You work together as a crew, you have to think of the others.”

Matthias Maurer, 50, the newest addition to the European Space Agency’s astronaut corps, said it was important to address any niggles before they blow up into arguments.

Read also: ‘Embrace your passion’: Confinement tips from French barrel sailor

“Everyone of us has a quirk which we are comfortable with but which can annoy others,” he said, recalling how his taste for bananas annoyed a colleague who couldn’t stand their smell.

“If he hadn’t said that so politely and clearly, I would have continually annoyed him,” said Maurer.

Alexander Gerst, 43, who commanded the International Space Station, addressed the anxiety people may feel during the coronavirus epidemic.

Before a mission, astronauts think about the worst that could happen and then train how to respond.

“Then you have the feeling not that you are losing control, but that you have some control over the situation,” he said.

“Now the situation is similar. We have a very effective means of limiting this illness – that is that we stay at home.”

Reiter urged people to act likes astronauts going into quarantine before a mission – a protocol to prevent illness in space.

“Some people take the attitude ‘I’m young, I’m not at danger, I have no symptoms, so I don’t need to pay attention’,” he said. “It is up everyone to behave appropriately now, just like for us in quarantine.” 

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Uranus has started leaking gas, NASA scientists confirm – Happy Mag

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As if 2020 couldn’t get any more cursed, NASA scientists looking back through decades-old data from the Voyager 2 spacecraft have discovered a mysterious gas escaping from Uranus.

The data showed some mysterious force sucking the atmosphere straight out of the planet and into space.

Uranus

Photo: NASA/JPL

Highly detailed and scientific NASA research can confirm that something massive is coming out of Uranus.

Buried data reveals that when the spacecraft flew past the gas giant in 1986, it passed through something called a plasmoid that escaped and stole a big old cloud of the planet’s atmosphere along with it.

NASA have learnt from Voyager 2’s gassy expedition that the plasmoid itself was about 127,000 miles long and twice as wide. The data, first published in August in the journal Geophysical Research Letters, will be able to give NASA a much more detailed understanding of Uranus’ atmospheric composition, however won’t be able to tell them everything.

“Imagine if one spacecraft just flew through this room and tried to characterise the entire Earth,” NASA researcher Gina DiBraccio said in a new press release. “Obviously it’s not going to show you anything about what the Sahara or Antarctica is like.”

NASA researchers are hypothesising that a similar unexpected release of gas may explain how Mars ended up as barren and dry as it is. However for this to be known for sure, NASA would have to fly another spacecraft back to Uranus and have a good rummage around.

“It’s why I love planetary science,” DiBraccio said. “You’re always going somewhere you don’t really know.”

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