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Poulsen et al. 2016. PLOS One.

Unique Glow Helps Identify Two New Fish Species

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Poulsen et al. 2016. PLOS One.

Scientists have found two new species of glowing fish with tube-shaped eyes and mirrors on their bellies, according to their research in journal PLOS One.

The Opisthoproctidae, or barreleyes, are a unusual family. For example, take a look at the transparent-headed, tiny-mouthed Macropinna microstoma. Those green objects pointing upward are its eyes, and what appear to be eyes at front are actually the barreleye equivalent of nostrils. 

Scientists have had a hard time getting to know the barreleyes better because the fishes’ delicate bodies kind of collapse once they’re out of the water. M. microstoma, for example, was first described in 1939, but nobody knew about its clear, fragile forehead until a remotely operated vehicle captured the video above in 2004.

Based on the evidence they had, researchers believed there were 19 species in the barreleye family. Some of these species have bioluminescent, or light-producing, organs in their bellies, along with mirror-like organs called soles that lie beneath the glow, controlling and directing its light.

During a research cruise in 2013 and 2014, the Japanese research vessel Hakuho-Maru pulled up four fish that looked like barreleyes. Researchers onboard the boat took tissue samples, then dropped the fish into ethanol and stored them in a sub-zero freezer to help the specimens keep their shape.

An international team of scientists took it from there. They examined and photographed the specimens and sequenced their DNA, then compared these results with data on existing barreleye species. They found that, while similar to one another, the new fishes’ mirror bellies showed three different types of markings. The DNA tests confirmed it: They were three different species, two of which had never been seen before. The new species were definitely barreleyes, but were so distinct from known species that the researchers put them in a separate genus, Monacoa. (They suggest calling them "long-nosed mirrorbellies" in the vernacular.)

Monacoa is what’s called a resurrected genus. A long time ago, ichthyologist GP Whitley believed he’d found a fish different enough from its kin to merit a new genus, which he named Monacoa. Later, other scientists disagreed, and moved Monacoa grimaldii into the genus Opisthoproctus. But based on the markings on the new fishes’ bellies, the authors of the current study say Whitley was right. They realized that the old specimens could never have led to this conclusion, as the formalin used to preserve the fish damaged their markings.

The two new species, M. niger and M. griseus, are both native to the Pacific Ocean. Unlike other fish that prefer pure blackness, these fish inhabit depths that still get some sunlight. In semi-lit conditions, the authors say, the barreleyes might use their bioluminescence as camouflage, or to communicate with one another. 

"This new study on the deep-sea has shown unknown biodiversity in a group of fishes previously considered teratological variations of other species," lead author Jan Poulsen of the Australian Museum said in a press statement. "The different species of mirrorbelly-tube eyes can only be distinguished on pigmentation patterns that also constitutes a newly discovered communication system in deep-sea fishes."

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Animals
25 Benefits of Adopting a Rescue Dog
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iStock

According to the ASPCA, 3.3 million dogs enter shelters each year in the United States. Although that number has gone down since 2011 (from 3.9 million) there are still millions of dogs waiting in shelters for a forever home. October is Adopt a Shelter Dog Month; here are 25 benefits of adopting a shelter dog.

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Brooklyn Museum, Charles Edwin Wilbour Fund, 37.406E
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Art
New Smithsonian Exhibit Explains Why Felines Were the Cat's Meow in Ancient Egypt
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Brooklyn Museum, Charles Edwin Wilbour Fund, 37.406E

From bi-coastal cat cafes to celebrity pets like Lil Bub, felines are currently enjoying a peak moment in popular culture. That’s part of the reason why curators at the Smithsonian’s Arthur M. Sackler Gallery—which will re-open to visitors on Saturday, October 14, following a 3-month closure—decided to dedicate a new exhibition to ancient Egypt’s relationship with the animals.

Divine Felines: Cats of Ancient Egypt” looks at the cultural and religious importance of cats, which the Egyptians appreciated long before YouTube was a thing and #caturday was a hashtag. It's based on a traveling exhibition that began at the Brooklyn Museum in New York City. On view until January 15, 2018, it's one of several exhibits that will kick off the grand reopening of the Smithsonian’s Freer and Sackler galleries, the conjoined national museums of Asian and Middle Eastern Art.

The Freer has been closed since January 2016 for major renovations, and the Sackler since July 2016 for minor ones. The upgraded institutions will make their public debut on October 14, and be feted by a free two-day festival on the National Mall.

Featuring 80 artworks and relics, ranging from figurines of leonine deities to the tiny coffins of beloved pets, "Divine Felines" even has a cat mummy on loan from the Smithsonian’s National Museum of Natural History. These objects span from the Middle Kingdom (2008 to 1630 BCE) to the Byzantine period (395 to 642 CE).

An ancient Egyptian metal weight shaped like a cat, dating back to 305 to 30 BCE, on view at the Smithsonian’s Arthur M. Sackler Gallery
Weight in Form of a Cat, 305 to 30 BCE, Bronze, silver, lead
Brooklyn Museum, Charles Edwin Wilbour Fund, 36.114

The term “cat” is used loosely, as the Egyptians celebrated domestic mousers and fearsome predators alike.

“The Egyptians were close observers of nature, so they were observing cat behaviors,” Antonietta Catanzariti, the exhibition's in-house curator, tells Mental Floss. “They noticed that cats and lions— in general, felines—have aggressive and protective aspects, so they associated those attributes to deities.”

The ancient Egyptians viewed their gods as humans, animals, or mixed forms. Several of these pantheon members were both associated with and depicted as cats, including Bastet, the goddess of motherhood, fertility, and protection; and Sakhmet, the goddess of war and—when appeased—healing. She typically has a lion head, but in some myths she appears as a pacified cat.

A limestone sculptor's model of a walking lion, on display at the Smithsonian's Arthur M. Sackler Gallery.
Sculptor's Model of a Walking Lion, ca. 664 to 630 BCE, limestone
Brooklyn Museum, Charles Edwin Wilbour Fund, 33.190

While Bastet was a nurturer, Sakhmet—whose name means “The Powerful One”—could use her mighty force to either slay or safeguard humanity. These characterizations are typical of the ancient Egyptian worldview, which perceived the universe in dualistic terms. “There’s always a positive and a negative,” Catanzariti explains.

Contrary to popular belief, however, ancient Egyptians did not view cats themselves as gods. “The goddess Sakhmet does have the features as a lion, or in some cases as a cat, but that doesn’t mean that the Egyptians were worshipping cats or lions,” Catanzariti says. Instead, they were simply noting and admiring her feline traits. This practice, to an extent, also extended to royalty. Kings were associated with lions and other large cats, as they were the powerful protectors of ancient Egypt’s borders.

These myriad associations prompted Egyptians to adorn palaces, temples, protective amulets, ceremonial vessels, and accessories with cat images. Depending on their context, these renderings symbolized everything from protection and power to beauty and sexuality. A king’s throne might have a lion-shaped support, for example, whereas a woman’s cosmetics case might be emblazoned with a cat-headed female goddess of motherhood and fertility.

An ancient Egyptian figurine of a standing lion-headed goddess, on display at the Smithsonian's Arthur M. Sackler Gallery.
Figurine of a Standing Lion-Headed Goddess, 664 to 630 BCE, Faience
Brooklyn Museum, Charles Edwin Wilbour Fund, 37.943E

While cats were linked with heavenly figures and kings, they were also popular domestic pets. Their ability to catch vermin made them an important addition to households, and owners loved and anthropomorphized their pets just like we do today.

Egyptians often named, or nicknamed, their children after animals; Miit (cat) was a popular moniker for girls. It's said that entire households shaved their eyebrows in mourning if a house cat died a natural death. Some also believe that cats received special legal protection. (Not all cats were this lucky, however, as some temples bred kittens specifically to offer their mummified forms to the gods.) If a favorite cat died, the Egyptians would bury them in special decorated coffins, containers, and boxes. King Tutankhamen, for example, had a stone sarcophagus constructed just for his pet feline.

An ancient Egyptian bronze cat head adorned with gold jewelry, on display at the Smithsonian's Arthur M. Sackler Gallery.
Cat's Head, 30 BCE. to third century CE, bronze, gold
Brooklyn Museum, Charles Edwin Wilbour Fund, 36.114

“Divine Felines” breaks down these facts, and more, into five thematic sections, including “Cats and Kings"; “Cats and Gods”; “Cats and Death”; “Cats and Protection”; and “Dogs as Guardians and Hunters.” Yes, there’s also an exhibition section for dog lovers—“a small one,” Catanzariti laughs, that explains why canines were associated with figures like Anubis, the jackal-headed god of mummification and the afterlife.

Did the ancient Egyptians prefer cats to dogs? “I would say that both of them had different roles,” Catanzariti says, as dogs were valued as hunters, scavengers, and guards. “They were appreciated in different ways for their ability to protect or be useful for the Egyptian culture.” In this way, "Divine Felines" is targeted to ailurophiles and canophiliacs alike, even if it's packaged with pointed ears and whiskers.

An ancient Egyptian cat coffin, on display at the Smithsonian's Arthur M. Sackler Gallery.
Coffin for a Cat, 664 to 332 BCE, or later, Wood, gesso, paint, animal remains
Brooklyn Museum, Charles Edwin Wilbour Fund, 37.1944Ea-b

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