Each week we uncover the most interesting and informative articles from around the world, here are 10 of the coolest stories in science this week.

Grizzly bear populations are on the rebound in Yellowstone.
Grizzly bear populations are on the rebound in Yellowstone.
Credit: Georgia Evans/Shutterstock

The U.S. Fish and Wildlife Service removed grizzly bears in the Greater Yellowstone Ecosystem from the Endangered Species List yesterday (June 22).

Grizzly bears "have long warranted delisting," as they have met or exceeded recovery objectives since 2003, Wyoming governor Matt Mead said in a statement published online by the governor's office. [Read more about the grizzly bears.]

Hieroglyphics found at El-Khawy in Egypt show two storks, back to back, with an ibis between them (left), as well as a bull's head (right).
Hieroglyphics found at El-Khawy in Egypt show two storks, back to back, with an ibis between them (left), as well as a bull's head (right).
Credit: Courtesy of Yale University

Archaeologists have discovered a "billboard" of hieroglyphs carved into the rocks near the Egyptian village of El-Khawy. The symbols, which show a message related to the cosmos, are the earliest monumental (large) hieroglyphs known, dating back around 5,200 years.

Only a few similar scenes are known from Egypt. For example, a vase previously found at the site of Abydos depicts a pregnant hippopotamus, Darnell told Live Science. [Read more about the cosmic message.]

Dried monitor lizard penises are being illegally traded as "Hatha Jodi," an Indian plant root used in religious ceremonies and thought to be a good-luck charm.
Dried monitor lizard penises are being illegally traded as "Hatha Jodi," an Indian plant root used in religious ceremonies and thought to be a good-luck charm.
Credit: World Animal Protection

Poachers have been caught trying to illegally sell dried lizard penises online to unwitting customers looking to purchase a rare Indian root called "Hatha Jodi." The root looks like two praying hands and is thought to bring good luck.

Investigation into the illegal trade determined that along with dried specimens from monitor lizards, plastic molds of the animal's genitalia were also being peddled as Hatha Jodi. [Read more about good-luck root.]

People who have insomnia may have been told that their sleeping troubles are "all in their head," but a new study shows that this condition is driven not only by psychological factors, but biological ones as well.

The researchers found that seven genes were more common in people who had insomnia, meaning that these seven genes could indicate that a person has an increased risk for the sleep disorder. [Read more about insomnia and your genes.]

This artist’s impression shows an imagined view from the surface of a planet that was part of a star system found recently using the TRAPPIST telescope at the European Space Observatory's La Silla Observatory in Chile. These worlds' sizes and temperatures are similar to those of Venus and Earth, and are the best targets found so far in the search for life outside our solar system.
This artist’s impression shows an imagined view from the surface of a planet that was part of a star system found recently using the TRAPPIST telescope at the European Space Observatory's La Silla Observatory in Chile. These worlds' sizes and temperatures are similar to those of Venus and Earth, and are the best targets found so far in the search for life outside our solar system.
Credit: ESO/M. Kornmesser

From the lovable, candy-munching E.T. to the deadly Xenomorphs from the "Alien" movies, science-fiction stories are bursting with all kinds of alien encounters. But in reality, we've yet to achieve contact — though not for lack of trying.

What we now know about the universe suggests that it's very unlikely that humanity is the only form of life in it. [Read more about the search for alien life.]

Stephen Hawking has a long list of warnings about threats to humanity.
Stephen Hawking has a long list of warnings about threats to humanity.
Credit: Flickr/NASA HQ PHOTO.

Humanity should focus its efforts on exploring other worlds that we might inhabit, and to get there, Earthlings may need to ride on a beam of light, famed physicist Stephen Hawking says.

To bring these seeming pipe dreams closer to reality, Hawking, along with physicist and billionaire Yuri Milner, has founded a company called Breakthrough Starshot, which aims to make interstellar travel a reality. [Read more about the strange idea.]

El Volcán in the Nepeña Valley of coastal Peru has archaeologists stumped as to when and why this mound was built, though it may have served as a place for a ceremony related to a total solar eclipse.
El Volcán in the Nepeña Valley of coastal Peru has archaeologists stumped as to when and why this mound was built, though it may have served as a place for a ceremony related to a total solar eclipse.
Credit: Courtesy of Robert Benfer

From far away, El Volcán in the Nepeña Valley of coastal Peru might look like a natural feature in the landscape.

But this volcano is artificial, a mound or pyramid built by human hands with a crater dug out of the top. And some archaeologists are trying to figure out what it was used for. [Read more about the strange pyramid.]

The boozy order found on the back of the pottery shard
The boozy order found on the back of the pottery shard
Credit: American Friends of Tel Aviv University (AFTAU)

A previously overlooked inky inscription on a pottery shard found in Israel calls for the delivery of more wine, according to a new study, showing that not much has changed in 2,600 years for humanity, at least when it comes to wetting our whistles.

"While its front side has been thoroughly studied, its back was considered blank," study co-principal investigator Arie Shaus, a doctoral student of applied mathematics and archaeology at Tel Aviv University (TAU) in Israel, said in a statement. [Read more about the shopping list.]

The Egyptian tomb-chapel of Nebamun, dating to about 1250 B.C., is on display at the British Museum. Notice the cat's stripes, which are reminiscent of a wildcat's markings.
The Egyptian tomb-chapel of Nebamun, dating to about 1250 B.C., is on display at the British Museum. Notice the cat's stripes, which are reminiscent of a wildcat's markings.
Credit: Copyright Thierry Grange

Modern cat lovers can thank the farmers of ancient Anatolia in the Near East for domesticating their fluffy friends about 10,000 years ago, a new study finds.

However, it wasn't until the Middle Ages, after thousands of years of living alongside humans, that some cats (Felis silvestris) developed fur with patch-like patterns, and not until the 19th century that they were bred to have fancy coats, the researchers found. [Read more about kitty genealogy.]

Stop the worlds, I want to get off.
Stop the worlds, I want to get off.
Credit: Victor Habbick/Shutterstock

By some estimates, the known universe may contain as many as 2 trillion galaxies, with the average galaxy holding approximately 100 million stars and untold numbers of planets. But could there be multiple copies of the entire universe as we understand it?

Multiple universes might also exist within contained bubbles of space-time, a concept explored in the video game "Bioshock Infinite." By this reckoning, inhabitants of two universes could theoretically interact should their "bubbles" connect to each other directly, according to Macdonald. [Read more about the missing worlds.]

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