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7 Vivid Facts About Sea Slugs

These “butterflies of the ocean” are beautiful, deadly, and strange.

1. THERE ARE MORE THAN 3000 SPECIES.

Bernard Picton, Wikimedia Commons // CC BY-SA 4.0

The bizarre, beautiful sea slugs called nudibranchs can be found in marine environments all over the world. Like orchids, nudibranchs vary widely in color and arrangement. Some sport the typical slug shape; others look like bottle brushes, internal organs, or Christmas ornaments.

2. THEY’RE NOT FOR EATING.

Sylke Rohrlach, Wikimedia Commons // CC BY-SA 2.0

Nudibranch expert Karen Cheney calls the slugs the “butterflies of the ocean,” both for their Technicolor appearance and their intense toxicity. Like the bright wings of butterflies, nudibranchs’ loud coloration is a warning sign to potential predators that the slugs are not worth the pain. Still, only a few species present much of a threat to humans. Anyone who grabs the blue dragon (Glaucus atlanticus), pictured above, will end up with a handful of regret. 

3. THEY’RE COLORBLIND.

Jerry Kirkhart, Wikimedia Commons // CC BY 2.0

In an O. Henry-style twist, a nudibranch will never see its own magnificence. Unlike the peepers of their terrestrial cousins, the eyes of sea slugs are extremely primitive and likely only detect light and dark. Nudibranchs do most of their navigating by scent, which they take in through the feather-like rhinophores on their heads.

4. SOME NUDIBRANCHS RUN ON GREEN ENERGY.

Karen N. Pelletreau et al., Wikimedia Commons // CC BY 4.0

Some nudibranch species have evolved the plant-like ability to photosynthesize, or live off sunlight. The Elysia chlorotica shown here swipes photosynthesizing cells and genes from the algae it eats. When there’s no algae to be found, the slug can run entirely on solar power. 

5. THEY CAN PLAY BOTH PARTS.

Leonard Clifford, Wikimedia Commons // CC BY 2.0

Like most snails and slugs, nudibranchs are hermaphroditic, which really lets them make the most of each mating encounter. Two slugs line up facing in opposite directions, then plug their penises into each other, giving and receiving sperm at the same time.

6. THEIR GLORY IS SHORT-LIVED.

Bernard Picton, Wikimedia Commons // CC BY-SA 4.0

Nudibranch lifespans vary by species, but none live to be more than a year old.

7. SOME ARE REALLY, REALLY CUTE.

Crawl_Ray, Flickr // CC BY-ND 2.0

The “sea bunny” nudibranch Jorunna parva took the Internet by storm last summer, and it’s easy to see why.

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Courtesy of The National Aviary
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Animals
Watch This Live Stream to See Two Rare Penguin Chicks Hatch From Their Eggs
Courtesy of The National Aviary
Courtesy of The National Aviary

Bringing an African penguin chick into the world is an involved process, with both penguin parents taking turns incubating the egg. Now, over a month since they were laid, two penguin eggs at the National Aviary in Pittsburgh, Pennsylvania are ready to hatch. As Gizmodo reports, the baby birds will make their grand debut live for the world to see on the zoo's website.

The live stream follows couple Sidney and Bette in their nest, waiting for their young to emerge. The first egg was laid November 7 and is expected to hatch between December 14 and 18. The second, laid November 11, should hatch between December 18 and 22.

"We are thrilled to give the public this inside view of the arrival of these rare chicks," National Aviary executive director Cheryl Tracy said in a statement. "This is an important opportunity to raise awareness of a critically endangered species that is in rapid decline in the wild, and to learn about the work that the National Aviary is doing to care for and propagate African penguins."

African penguins are endangered, with less than 25,000 pairs left in the wild today. The National Aviary, the only independent indoor nonprofit aviary in the U.S., works to conserve threatened populations and raise awareness of them with bird breeding programs and educational campaigns.

After Sidney and Bette's new chicks are born, they will care for them in the nest for their first three weeks of life. The two penguins are parenting pros at this point: The monogamous couple has already hatched and raised three sets of chicks together.

[h/t Gizmodo]

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holidays
Bleat Along to Classic Holiday Tunes With This Goat Christmas Album
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iStock

Feeling a little Grinchy this month? The Sweden branch of ActionAid, an international charity dedicated to fighting global poverty, wants to goat—errr ... goad—you into the Christmas spirit with their animal-focused holiday album: All I Want for Christmas is a Goat.

Fittingly, it features the shriek-filled vocal stylings of a group of festive farm animals bleating out classics like “Jingle Bells,” “Rudolph the Red-Nosed Reindeer,” and “O Come All Ye Faithful.” The recording may sound like a silly novelty release, but there's a serious cause behind it: It’s intended to remind listeners how the animals benefit impoverished communities. Goats can live in arid nations that are too dry for farming, and they provide their owners with milk and wool. In fact, the only thing they can't seem to do is, well, sing. 

You can purchase All I Want for Christmas is a Goat on iTunes and Spotify, or listen to a few songs from its eight-track selection below.

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