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Dr. Alan Jamieson, Newcastle University
Dr. Alan Jamieson, Newcastle University

Our Pollution Has Now Reached Deep-Sea Animals

Dr. Alan Jamieson, Newcastle University
Dr. Alan Jamieson, Newcastle University

It seems nowhere on Earth is safe from the creeping, deadly fingers of pollution. Scientists analyzing deep-sea crustaceans found traces of manmade chemicals in the animals’ bodies. The researchers published their findings in the journal Nature Ecology & Evolution.

Amphipods, like the one shown above, are small, eyeless crustaceans that make their homes in the deepest, darkest parts of the ocean. The key to the deepwater amphipod’s survival is its stomach; it is both notoriously unfussy about what it eats, and gifted with special enzymes that help it digest just about anything, including plastic, animal carcasses, and even sunken ships.

But the oceans are a risky place to dine these days. Scientists have found dangerous chemicals, fibers, and pieces of plastic in the bodies of seabirds, mammals, mollusks, and fish alike.

The question for oceanographer Alan Jamieson and his colleagues was simple: How far down do these pollutants go?

To find out, they used deep-sea landers to collect three species of amphipods from the Mariana and Kermadec Trenches in the Pacific Ocean. They brought the animals back to the lab and tested their fatty tissue, looking for traces of 14 different pollutants.

And there they were. High levels of pollutants, including flame retardant chemicals, were found in every sample from every species, regardless of the depth at which the sample was collected. The contamination was so bad, it was comparable to that found in Japan's Suruga Bay, long known for its high level of industrial pollution.

The authors say the chemicals most likely reached the trenches while clinging to pieces of plastic garbage or the bodies of dead animals from closer to the surface.

Biologist Katherine Dafforn of the University of New South Wales weighed in on the research in an accompanying editorial. She concludes that “Jamieson et al. have provided clear evidence that the deep ocean, rather than being remote, is highly connected to surface waters and has been exposed to significant concentrations of human-made pollutants.”

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Animals
Where Do Birds Get Their Songs?
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iStock

Birds display some of the most impressive vocal abilities in the animal kingdom. They can be heard across great distances, mimic human speech, and even sing using distinct dialects and syntax. The most complex songs take some practice to learn, but as TED-Ed explains, the urge to sing is woven into songbirds' DNA.

Like humans, baby birds learn to communicate from their parents. Adult zebra finches will even speak in the equivalent of "baby talk" when teaching chicks their songs. After hearing the same expressions repeated so many times and trying them out firsthand, the offspring are able to use the same songs as adults.

But nurture isn't the only factor driving this behavior. Even when they grow up without any parents teaching them how to vocalize, birds will start singing on their own. These innate songs are less refined than the ones that are taught, but when they're passed down through multiple generations and shaped over time, they start to sound similar to the learned songs sung by other members of their species.

This suggests that the drive to sing as well as the specific structures of the songs themselves have been ingrained in the animals' genetic code by evolution. You can watch the full story from TED-Ed below, then head over here for a sample of the diverse songs produced by birds.

[h/t TED-Ed]

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NOAA, Wikimedia Commons // Public Domain
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Animals
Watch the First-Ever Footage of a Baby Dumbo Octopus
NOAA, Wikimedia Commons // Public Domain
NOAA, Wikimedia Commons // Public Domain

Dumbo octopuses are named for the elephant-ear-like fins they use to navigate the deep sea, but until recently, when and how they developed those floppy appendages were a mystery. Now, for the first time, researchers have caught a newborn Dumbo octopus on tape. As reported in the journal Current Biology, they discovered that the creatures are equipped with the fins from the moment they hatch.

Study co-author Tim Shank, a researcher at the Woods Hole Oceanographic Institution in Massachusetts, spotted the octopus in 2005. During a research expedition in the North Atlantic, one of the remotely operated vehicles he was working with collected several coral branches with something strange attached to them. It looked like a bunch of sandy-colored golf balls at first, but then he realized it was an egg sac.

He and his fellow researchers eventually classified the hatchling that emerged as a member of the genus Grimpoteuthis. In other words, it was a Dumbo octopus, though they couldn't determine the exact species. But you wouldn't need a biology degree to spot its resemblance to Disney's famous elephant, as you can see in the video below.

The octopus hatched with a set of functional fins that allowed it to swim around and hunt right away, and an MRI scan revealed fully-developed internal organs and a complex nervous system. As the researchers wrote in their study, Dumbo octopuses enter the world as "competent juveniles" ready to jump straight into adult life.

Grimpoteuthis spends its life in the deep ocean, which makes it difficult to study. Scientists hope the newly-reported findings will make it easier to identify Grimpoteuthis eggs and hatchlings for future research.

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