Jellyfish Serve as Lobster Taxis — and Dinner

By Nathaniel Scharping | August 25, 2016 4:11 pm
Scyllarides_latus

A slipper lobster, a close relative of smooth fan lobsters. (Credit: Peter Koelbl/Wikimedia Commons)

Life as a young smooth fan lobster is pretty easy.

As a phyllosoma, another word for lobster larvae, the crustaceans like to kick back and relax, hitching rides on Moon jellyfish instead of using their own legs to get around. What’s more, they never really have to get off because they also eat the jellyfish. It’s like taking an Uber everywhere, only the car is made out of chocolate. But how do lobsters survive on their deadly hosts?

The answer could help make it easier to keep lobster on the menu.  Read More

CATEGORIZED UNDER: Living World

This ‘Ghost Galaxy’ Is 99.99% Dark Matter

By Ryan F. Mandelbaum | August 25, 2016 1:42 pm

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The hazy oval isn’t glare on your screen; it’s an entire galaxy. Dragonfly 44 weighs about the same as our Milky Way, except it’s 99.99 percent dark matter and has less than a hundredth the number of stars. Dark matter is stuff that can’t interact with the electromagnetic force (how we mostly experience the world) so we can’t see or touch it.

Scientists can observe its gravitational effects, though, which keep Dragonfly 44’s paltry collection of visible stars from flying apart. There’s around five times as much dark matter as regular matter in the universe, and even our own Milky Way is around 90% dark matter. Read More

CATEGORIZED UNDER: Space & Physics, top posts
MORE ABOUT: dark matter

Algorithm Weaves Secret Messages into Dance Music

By Nathaniel Scharping | August 24, 2016 3:54 pm
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(Credit: PHOTOCREO Michal Bednarek/Shutterstock)

In Ibiza, an island in the Mediterranean Sea, the hypnotic “thump thump thump” of the club music could actually convey much more than a call to dance.

Krzysztof Szczypiorski, a researcher from Poland, has developed a technique to hide messages inside dance music using subtle variations in tempo. By raising or lowering the speed of the music at levels not detectable by humans, he transmits a series of Morse code-like signals that can be picked up by a computer program. The sonic dots and dashes are then put together to spell out a message. Read More

CATEGORIZED UNDER: Technology, top posts
MORE ABOUT: computers

Alpha Centauri: The Hollywood Star System

By Nathaniel Scharping | August 24, 2016 12:05 pm
(Credit: Wikimedia Commons)

(Credit: Wikimedia Commons)

With the announcement today of an Earth-sized planet orbiting in the habitable zone of Proxima Centauri, Earthlings’ attention is focused once again on our nearest stellar neighbor.

The Alpha Centauri system is located some 4 light years away from Earth, which places it right in our backyard, cosmically speaking, even though it still lies roughly 25 trillion miles away from us. Spotting an exoplanet around Proxima is a huge discovery scientifically speaking, but it’s all the more exciting given the cultural significance of the Alpha Centauri system.

In a way, it validates the speculations of dozens of authors, directors, comic book artists and game designers who dared to dream of life somewhere out there.

We don’t know if anything actually exists — or even can exist — on the planet, named Proxima b, but the discovery will no doubt fuel the imaginations of a new generation of science fiction writers whose ideas now have evidence to back them up. Read More

CATEGORIZED UNDER: Space & Physics, top posts

Chimpanzee Groups Know How to Deal With Freeloaders

By K. N. Smith | August 23, 2016 12:00 pm
chimpanzees-cooperating

Three chimpanzees pull at the cooperation apparatus, with two others looking on. (Credit: Courtesy of Frans de Waal, Yerkes National Primate Research Center)

Chimpanzees are known to be violently competitive in groups — they aren’t exactly team players.

But given enough time, it appears they can work together to stifle competition, police freeloaders and cooperatively accomplish a task. Doesn’t that sound familiar?

Human society works because we all agree on certain social norms, and we hold each other to them. The old argument is that our ability to make society work by deploying these enforcement mechanisms is a uniquely human skill set. Read More

CATEGORIZED UNDER: Living World, top posts

Why Scientists Created See-through, Shrunken, Glow-in-the-dark Mice

By Nathaniel Scharping | August 22, 2016 3:48 pm
Figure-3b--whole-rat-body-before-uDISCO-clearing

A whole rat made transparent with uDISCO (Credit: Ali Ertuerk)

When Victorian anatomists wanted to take a peek under the skin, they were forced to cut into the very objects they meant to study. It was really their only option, of course, as techniques such as X-rays and MRIs wouldn’t enter the lab for many years.

Today, scientists can see into bodies without ever opening them up, but their visualizations still fail to completely capture their subjects’ inner essence. The stubborn opacity of skin and organs defeats our eyes.

To give us an altogether new form of insight, researchers are making the bodies we want to peer into entirely transparent. The idea of leaching the color from organic structures has existed for several years now, but researchers from Germany say that they have created the most effective method to date. And, not only are these mice transparent, they glow in the dark as well. The technique also shrinks the mice down to about a third of their former volume, leaving the researchers with a tiny, see-through mouse that glows radioactive green. Read More

An Alaskan Village Prepares to Move As the Sea Encroaches

By Nathaniel Scharping | August 19, 2016 2:27 pm
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The village of Shishmaref seen from the air. (Credit: Wikimedia Commons)

A small Alaskan village near the Arctic Circle has voted to pack up and move as its island slips into the sea due to climate change.

Despite the grim circumstances, the vote among villagers was close, with 89 supporting a move and 78 opposing it. The nearly even split speaks to the difficulty of severing ties with a place that has harbored family generations for over four centuries, providing shelter, sustenance and comfort in a place reachable only by boat, plane and sometimes snowmobile. Read More

CATEGORIZED UNDER: Environment

Where Fish Pee, Corals Grow

By Nathaniel Scharping | August 18, 2016 3:16 pm
shutterstock_92528491

You can’t see it, but these fish are spreading nutrients all over. (Credit: Tischenko Irena/Shutterstock)

There’s something in the water around coral reefs. And that something is fish pee. Although you may cringe at the thought of swimming through clouds of urine, coral reefs wouldn’t be the same without fishes’ urinary benevolence.

Fish excretion may be the furthest thing from your mind as you swim through a vibrant coral reef, but it a plays a vital, though underappreciated, role in supporting the diversity of life under the sea. That’s because it contains two important elements: nitrogen and phosphorous. Fish spread them around by ingesting plants and other fish, extracting the nutrients through the digestive process and then excreting them as they swim. From there, the nitrogen and phosphorus go on to feed the algae that sustain corals.

Overlooked Element

University of Washington ecologist Jacob Allgeier has been studying the importance of fish pee in the Bahamas for several years now and has published papers showing that coral reefs, which get little outside nutrient input, thrive only when these nutrient levels remain within a fairly narrow band. He focuses on the role fish play in this process — specifically how overfishing and changes to fish populations negatively impacts reefs by upsetting the delicate chemical equilibrium that the critters help maintain.

In his latest study, published Tuesday in Nature Communications, Allgeier narrowed his focus to figure out which kinds of fish were important to reefs. So he captured hundreds of fish and temporarily held them in his version of make-shift test tubes — water-filled plastic bags. His goal was to find out how many nutrients different kinds of fish put into the water. He looked for concentrations of both nitrogen and phosphorus, testing the water before and after a fish had been held in the bag for half an hour. In total, Allgeier gathered data from 143 species across 43 Caribbean reefs.

Top of the Food Chain

He concluded that when it comes to reefs, it’s the big fish that matter most — the predators on the top of the fish food chain. These scaly sea fauna, including groupers, snappers and barracuda, tend to produce more phosphorus than small fish, meaning that removing them from the reef can cause a harmful shift in the ratio of nutrients in the water.

Unfortunately, they also happen to be the most desirable to fishermen in the region. In the same study, Allgeier compared heavily fished reefs to those protected by marine reserves and found that overfished reefs had half as many essential nutrients as those that were protected. The reefs’ distance from populated areas was another important factor in determining whether nutrient levels were affected.

In oceans where reefs are already under threat from warming waters, rising acidification and even viruses, further altering their intricately composed environment comes as just another straw on their backs. We might not ever really think of, or see, fish pee, but take it away, and a stage in the cycle of reef life goes with it.

CATEGORIZED UNDER: Living World
MORE ABOUT: animals, ecology

A Dormant Beast Just Went Nova

By Ryan F. Mandelbaum | August 17, 2016 4:31 pm

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White dwarf-companion star binaries can have explosive relationships. They begin with a hibernation phase, where the companion sends a whisper of mass to the white dwarf as a stream of hydrogen. The white dwarf cyclically brightens and dims and then awakes, erupting in a nova, a stellar nuclear explosion on its surface causing the white dwarf to get far brighter, and the companion sends even more mass over. The process slows and eventually starts all over again. Read More

CATEGORIZED UNDER: Space & Physics, top posts
MORE ABOUT: stars

Fish Fins and Fingers: A Surprising Cellular Connection

By Nathaniel Scharping | August 17, 2016 1:40 pm
The same group of cells (highlighted in green) is responsible for creating digits in mice (left) and fin rays in fish (right). (Credit: Shubin Laboratory)

The same group of cells (highlighted in green) is responsible for creating digits in mice (left) and fin rays in fish (right). (Credit: Shubin Laboratory)

Millions of years ago our ocean-dwelling ancestors stepped forth onto new shores and began populating Earth’s dry land.

Fossils such as Tiktaalik, one of the most compelling members of the class of transitional “lobe-finned fishes”, mark the evolutionary path that led to land-bound animals. The transition from delicate fins to sturdy limbs didn’t happen all at once, but it is clear that our appendages are distant cousins of fish fins.

Using cutting-edge DNA mapping techniques, researchers from the University of Chicago have discovered fins and fingers emerge from the same group of embryonic cells, shedding light on how our earliest ancestors made landfall.

Read More

CATEGORIZED UNDER: Living World, top posts
MORE ABOUT: animals, evolution, genetics
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