Could a Corpse Seed Life on Another Planet?

By William Herkewitz | October 25, 2016 10:40 am
an astronaut drifts through space

(Credit: Shutterstock)

One day, it’s bound to happen. An astronaut dies in space.

Maybe the death occurred en route to Mars. Maybe she was interstellar, on board solo spacecraft. Or maybe the body was thrust out an airlock, a burial at space.

That corpse (or the corpse’s spacecraft) could spend anywhere from decades to millions of years adrift. It would coast listlessly in the void, until the creeping tendrils of gravity eventually pulled it into a final touchdown. Likely this corpse will burn up in a star.

But lets say it lands on a planet. Could our corpse, like a seed on the wind, bring life to a new world? Read More

CATEGORIZED UNDER: Space & Physics, Top Posts

Wanted: Stem Cell Super Donors

By Kim Smuga-Otto | October 24, 2016 3:16 pm
Pictured is a microscopic view of brain cells generated from induced pluripotent stem cells in the laboratory of University of Wisconsin-Madison neuroscientist Su-Chun Zhang. The induced cells, derived from reprogrammed skin cells, seem to have many of the all-purpose qualities of human embryonic stem cells, but a team led by Zhang, writing in the Feb. 15, 2010, edition of the Proceedings of the National Academy of Sciences, reports the induced cells seem to differentiate less efficiently and faithfully than their embryonic counterparts. Used and distributed with permission by: UW-Madison University Communications 608/262-0067 Photo by: courtesy Su-Chun Zhang/Baoyang Hu, UW-Madison Date: 2010 File#: file provided 02/10

Pictured is a microscopic view of brain cells generated from induced pluripotent stem cells in the laboratory of University of Wisconsin-Madison neuroscientist Su-Chun Zhang. (Courtesy: Su-Chun Zhang/Baoyang Hu, UW-Madison)

Our bodies’ cells didn’t evolve to flourish in a petri dish. Even fast-growing skin cells stop dividing and turn thin and ragged after a few weeks outside the body. This natural obstacle limited the therapeutic potential of lab-grown cells – if you can’t grow the cells, you can’t use them to heal damaged tissue.

Then, a decade ago, Nobel Prize winner Shinya Yamanaka identified a cocktail of genes that, when added to mouse skin cells, transformed them into a new kind of cell that grew happily in ever expanding colonies. More importantly, these cells, dubbed “induced pluripotent stem cells” (iPSC), had their internal clocks set back to an earlier stem cell-like state, giving them the ability to grow into any other cell type found in the body. Read More

CATEGORIZED UNDER: Health & Medicine, Top Posts

Can Science Save the Banana?

(Credit: Shutterstock)

(Credit: Shutterstock)

The banana is the world’s most popular fruit crop, with over 100 million metric tons produced annually in over 130 tropical and subtropical countries. Edible bananas are the result of a genetic accident in nature that created the seedless fruit we enjoy today. Virtually all the bananas sold across the Western world belong to the so-called Cavendish subgroup of the species and are genetically nearly identical. These bananas are sterile and dependent on propagation via cloning, either by using suckers and cuttings taken from the underground stem or through modern tissue culture.

The familiar bright yellow Cavendish banana is ubiquitous in supermarkets and fruit bowls, but it is in imminent danger. The vast worldwide monoculture of genetically identical plants leaves the Cavendish intensely vulnerable to disease outbreaks. Fungal diseases severely devastated the banana industry once in history and it could soon happen again if we do not resolve the cause of these problems. Plant scientists, including us, are working out the genetics of wild banana varieties and banana pathogens as we try to prevent a Cavendish crash. Read More

CATEGORIZED UNDER: Living World, Top Posts
MORE ABOUT: agriculture

Why Our ‘Procrastinating’ Brains Still Outperform Computers

By Parashkev Nachev, UCL | October 21, 2016 3:56 pm

(Credit: Shutterstock)

Automated financial trading machines can make complex decisions in a thousandth of a second. A human being making a choice – however simple – can never be faster than about one-fifth of a second. Our reaction times are not only slow but also remarkably variable, ranging over hundreds of milliseconds.

Is this because our brains are poorly designed, prone to random uncertainty – or “noise” in the electronic jargon? Measured in the laboratory, even the neurons of a fly are both fast and precise in their responses to external events, down to a few milliseconds. The sloppiness of our reaction times looks less like an accident than a built-in feature. The brain deliberately procrastinates, even if we ask it to do otherwise. Read More

CATEGORIZED UNDER: Mind & Brain, Top Posts

In Pursuit of the ‘Cosmopolitan Chicken’

By Nathaniel Scharping | October 14, 2016 12:29 pm

The Mechelse Redcap crossbreed created by Koen Vanmechelen. (Credit: Koen Vanmechelen)

Let us consider the humble chicken.

Or, rather, consider a world without them. Gone are breakfast burritos at Sunday morning brunch, wings at your next tailgate, half the menu at an Italian restaurant, your grandma’s precious soup recipe and nearly every fast-food chain out there. It’s a bleak world, to be sure. 

Given the extent to which we rely on the nameless, faceless birds that gift us so many culinary delights, perhaps it’s time we paid more attention to them. That’s the insight behind the Cosmopolitan Chicken Project, an artistic endeavor 20 years in the making. It’s the brainchild of Belgian artist Koen Vanmechelen, and it celebrates the wonder and power of the riotous diversity found in the myriad lineages of chickens the world over. Read More

CATEGORIZED UNDER: Living World, Top Posts
MORE ABOUT: animals

5 Ways Yeast Will Help Save Lives

By Carl Engelking | October 6, 2016 2:09 pm
A bowl of dried yeasts. (Credit: Shutterstock)

A bowl of dried yeast. (Credit: Shutterstock)

Try to imagine life without yeast. It’s kind of a bummer.

The single-celled fungi are the leavening agents that gave rise to sourdoughs, ciabattas and chewy pizza crusts. They’re the microorganisms that convert sugar into carbon dioxide and ethanol to give beer and wine its intoxicating effects. They are used to produce insulin. You can buy yeast supplements. Yeast also played an instrumental role in a Nobel Prize win earlier this week.

Yeast, it turns out, is a life-saver. Although there are some 1,500 different species, it is one of the most well studied eukaryotic organisms known to science, and it’s serving on the front lines as a model organism for cutting-edge research in genetics, biology, agriculture and medicine.

Here are five reasons we owe this simple organism a debt of gratitude. Read More

CATEGORIZED UNDER: Living World, Top Posts
MORE ABOUT: microbes & viruses

Flesh-Eating Bacteria Like It Hot

By Hannah Gavin | September 30, 2016 12:05 pm
Vibrio vulnificus bacteria. (Credit: Wikimedia Commons)

Vibrio vulnificus bacteria. (Credit: Wikimedia Commons)

It’s spring, and I’m attending a luxurious seafood banquet. Platters of shellfish fill the tables: crab with limbs akimbo; shrimp ready to be peeled; miniature lobster-like langostino peering at my dinner plate as if knowing their fate. Raw oysters sit in the center of the platter, piled absurdly high and shimmering luminescent on the half shell.

Until now, I’ve never eaten a raw oyster. I apply a generous squirt of lemon juice and watch the white-grey flesh ripple ominously in reply. Tilting my head back, I down the shell’s contents in one shot of citrusy ocean. The gelatinous solid slides down my throat largely unchewed as I submit a silent prayer to the gods of food safety, asking not to become the subject of an ironic headline:

“Research scientist studying bacterium found in raw oysters falls ill after eating…a raw oyster.”

Thankfully, I walked away from the banquet without encountering Vibrio vulnificus, the bacterial subject of my Ph.D. Much as I want to be an academic expert on V. vulnificus, there are aspects of the microbe I hope never to attest to first-hand. But as the planet’s oceans heat up, the odds of a potentially fatal rendezvous will continue rise along with the temperature. Read More

CATEGORIZED UNDER: Health & Medicine, Top Posts

When Did Sex Become Fun?

By Holly Dunsworth | September 30, 2016 10:41 am

The reproductive organs of a lily. (Bryan Neuswanger/Shutterstock)

(This post originally appeared in the online anthropology magazine SAPIENS. Follow @SAPIENS_org on Twitter to discover more of their work.) 

There are multiple answers to the question of where we come from: early hominins, monkeys, primordial goo, or the Big Bang, to name a few. Today’s answer, though, has probably, just a split second ago, popped into many readers’ minds. Today’s answer is sexual intercourse, a.k.a. “bleeping.” So let’s go back to the beginning, hundreds of millions of years before we invented euphemisms and censorship, and let’s ask: How in the evolutionary world did sex begin?

Algae, the green gunk that runs amok in our fish tanks, as well as the seaweed that stinks up our summer beaches, include some of the simplest sexually reproducing organisms on Earth. These lineages go back nearly 2 billion years. Algae do it. Plants do it. Insects do it. Even fungi do it. Much of this sex involves releasing sperm into the wind or the water so they can be carried to nearby eggs (as in mosses), relying on a different species to carry male gametes to female ones (many flowers), or maneuvering two bodies so that the openings to the internal reproductive organs are close enough together for fluid exchange (most insects and most birds). Read More

CATEGORIZED UNDER: Health & Medicine, Top Posts

17th-century Ruins Could Unravel Mysteries of Earth’s Magnetic Field

By Andrew Jenner | September 28, 2016 4:14 pm

Jesuit church ruins from the 17th century, like the São Miguel das Missões, were built with clay bricks that contain magnetite, which realigned with earth’s magnetic field when it was fired in kilns. (Credit: Wikimedia Commons) 

It seems safe to say that the laborers firing clay pavers, bricks and tiles to build the Jesuit mission of Santo Ângelo over 300 years ago had no idea that their toils might someday bear relevance to spacecraft orbiting 600 miles above what is now southern Brazil.

As the bricks and pavers were fired in kilns, magnetite in the clay abandoned its inherent magnetic properties and realigned in response to the magnetic forces exerted by the earth itself. The point at which this occurs – 580 degrees Celsius, in the case of magnetite – is known as the Curie point.

After these building materials cooled and were stacked to form a church, school and other buildings at Santo Ângelo, the magnetite inside retained this reshuffled alignment, a record of the magnetic past sealed away like a proverbial mosquito in amber. Along with several dozen other Jesuit missions built in the same era, Santo Ângelo flourished briefly along what was then the poorly defined border between the Spanish and Portuguese colonies in South America. At its height, the mission was home to about 8,000 people, nearly all of them indigenous Guarani whom the Jesuits were trying to Christianize.

Read More

CATEGORIZED UNDER: Living World, Top Posts

The Arrow of Time? It’s All in Our Heads

By Robert Lanza, Wake Forest University | September 26, 2016 9:45 am


Have you ever wondered why we age and grow old?

In the movie “The Curious Case of Benjamin Button,” Brad Pitt springs into being as an elderly man and ages in reverse. 

To the bafflement of scientists, the fundamental laws of physics have no preference for a direction in time, and work just as well for events going forward or going backward in time.  Yet, in the real world, coffee cools and cars break down. No matter how many times you look in the mirror, you’ll never see yourself grow younger. But if the laws of physics are symmetric with respect to time, then why do we experience reality with the arrow of time strictly directed from the past to the future?

A new paper just published in Annalen der Physik — which published Albert Einstein’s theories of special and general relativity — Dmitry Podolsky, a theoretical physicist now working on aging at Harvard University, and I explain how the arrow of time ‒ indeed time itself ‒ is directly related to the nature of the observer (that is, us).

Our paper shows that time doesn’t just exist “out there” ticking away from past to future, but rather is an emergent property that depends on the observer’s ability to preserve information about experienced events. Read More

CATEGORIZED UNDER: Space & Physics, Top Posts
MORE ABOUT: physics

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