What color would Earth look like to aliens?

Welcome, ladies, gentlemen, everybody, to Friday. To greet the end of the week, I want to ask: What do you think Earth would look like if it were orbiting a different star?

This is not the premise of a sci-fi novel. Rather, it is the question Passant Rabie poses in her latest story on how the color of alien worlds could provide clues as to whether these distant planets may actually host life of some kind.

It’s our top story of the day. But keep scrolling for more fascinating reports on the discovery of a brain-immune system communication circuit critical to understanding how we store and burn fat, and three strange ancient creatures that could change how you think about mammals.

I’m Claire Cameron, and this is Inverse Daily. Tell a friend to subscribe using this link.

This is an adapted version of the Inverse Daily newsletter for Friday, August 20, 2021. Subscribe for free and earn rewards for reading every day in your inbox. ✉️

Look: 3 prehistoric mammals show how quickly life evolved after the dinosaurs — After the Cretaceous beasts were wiped out, small mammals began to populate the Earth — and get bigger, thanks to more available habitats and food resources. Jenn Walter shows you what we mean in her latest visual feast for Inverse.

As Walter explains, perhaps as much as 93 percent of mammalian life went extinct along with non-avian dinosaurs. Yet just a few hundred thousand years later — a small drop in the ocean on Earth-time scale — mammals began to rise once more, spreading, and diversifying rapidly.

Scientists have just discovered the remains of three of these ancient mammals in Wyoming. Together, they help to paint a picture of what life in this fractious period of Earth’s history was like. Surprisingly, these creatures were all really quite small — the largest was as big as a typical cat, the researchers report.

See the creatures.

Related links:

• When Texas was chaos: This ancient discovery puts the state in a new light
• The real Paleo diet: Scientists debunk ancient food myths
• Listen to the haunting music of ancient peoples for first time in 18,000 years

How can scientists find alien worlds? They can hunt for one special color — A new study examines what Earth would look like if it were orbiting different stars as a way to look for alien planets. Passant Rabie explains what this has to do with a fundamental process to do with plants and other life on Earth: Photosynthesis.

During photosynthesis, cells within vegetation take in carbon dioxide and energy from the Sun and make sugar molecules and oxygen. Photosynthesis, in turn, leaves a distinct signature on the wavelengths reflected by the Earth, known as the “red edge.”

A paper published in the journal Frontiers in Astronomy and Space Sciences suggests that on other planets, the red edge would not be red — if those planets don’t contain life. As scientists hunt for planets that could host alien life, observing the color of the planets’ wavelengths may be a clear indication there’s life existing beyond Earth.

What the scientists say: “If photosynthetic organisms around other stars exhibit similar edge-like spectral reflectance features, we might expect red edge analogs to occur on the long-wavelength side of the optimal pigment absorption.”

Read the full story.

Read these next:

• Phobos: Why the largest Martian moon may reveal alien life
• Ancient aliens: the millennia-long history of obsessing about extraterrestrials
• Young, hot-headed stars could actually be good hosts for life

Men feel better about aging than women, study shows — A study published Wednesday in the journal PLoS ONE looked at the gender disparity in individual attitudes toward longevity in Japan. Elana Spivack has more:

There is now quantifiable evidence to suggest that men really do have a sunnier outlook on aging than do women — and in turn, they are also more interested in staying alive for longer. This may be the first empirical study to examine individual attitudes toward aging in our super-aging society.

Research shows women tend to outlive men, yet these data suggest men are more inclined to embrace aging with open arms. Female study participants were 15 percent less likely than their male counterparts to believe longevity is a good thing.

This isn’t the first time men have been highlighted as a population that embraces longevity. Gender inequity, among other things, can account for this dramatic difference. There is a theory that women are less keen on living forever because they’re more likely to face daily trials and tribulations and shoulder the burden of aging more than men.

Key quote: “Understanding people’s outlook on aging can give us a lot of information on the next steps of how to get people to view aging more in a more positive outlook.”

Read the full story.

More longevity stories:

• Scientists say this invisible exercise counts more than your workout
• Five reasons drinking coffee improves brain power
• How fast we age may hinge on one unexpected mineral

‘Deep fat’ study reveals a surprising brain-immune system connection — Visceral or deep fat is the so-called “hidden” fat around our organs. Inverse contributor Sofia Quaglia reports on a new study in Nature that examines fat in the context of the brain and immune-system cells.

The study shines a light on the mechanics of how the brain and body work in tandem via the peripheral nervous system. This refers to the nerve endings that regulate physiological processes in the body without the brain having to consciously think about them, like blood pressure.

The study’s senior author, Henrique Veiga-Fernandes tells Inverse that a roadmap of these connections has been “lacking.” Veiga-Fernandes is a principal investigator and co-director at the Champalimaud Research Programme in Portugal.

“It’s sort of a forgotten cousin of the brain, which is understandable because everybody relates to the brain. But the brain needs to communicate with the periphery,” he says.

Read the full story.

Delve deeper:

• Beige fat study hints at immune system and metabolism connection
• Mysteriously “slimy” mice lead to surprise fat loss discovery
• Scientist debunks the most confusing myth about eating fat

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