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Slow, but Scary, Killer Snails


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The killers in some classic slasher movies are notoriously slow. Jason Voorhees, Michael Myers, and Leatherface all shamble along at a pace that makes little old ladies look like Usain Bolt. It’s got to be frustrating for someone with murder on their mind to get outrun by their victims. But real-world slow-and-scaries, the predatory cone snails of the genus Conus, have evolved a frightening way to make up for their speed deficit: venomous, harpoon-like teeth that can stab prey and drag them to the snail.

The snails bury themselves in the sand and lie in wait or sneak up on their prey, using a specialized chemical-sensory organ to detect a meal. Once a victim is in range, the snail strikes. It points its long, flexible proboscis at its victim and launches a modified radular tooth—hollow, barbed and made of chitin—from it. The tooth is loaded with a cocktail of neurotoxins that reduce pain to pacify the prey and quickly paralyze it by blocking neurotransmitter receptors. The tooth is still attached to the radula structure, so once the prey is subdued, the snail draws both the tooth and its dinner right into its mouth. After the meal has been processed, the snail pukes up any leftover indigestible bits along with the used tooth, and readies another one to fire. You can see the a snail do the jab-and-grab and then swallow a fish whole in this National Geographic video.

The snail’s venom gland and the toxins it makes have fascinated scientists for more than a century. A researcher from Canada’s University of Victoria recently discovered that the venom glands of the species C. lividus come from a bit of “epithelial [tissue] remodeling” and are formed when a part of the esophagus pinches off as the snail transitions into adulthood. The researcher suggests that this tissue tweaking process allowed the snail to develop its weaponry and become carnivorous in a relatively short evolutionary timeframe.

Meanwhile, the speed and precision of the snails’ venom have led other researchers to look into it for medical use as a painkiller with few or no side effects. One painkiller derived from the snails’ arsenal has already been approved by the FDA. “Prialt” contains ziconotide, a synthetic equivalent of one of the snails’ many toxins, and is approved for use in treating chronic pain in patients with cancer and AIDS. Dozens of other cone snail toxins are still being investigated for use in pain relief and treating epilepsy, cardiovascular disease, Alzheimer’s, Parkinson’s, and other diseases and disorders.

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Department Of Classics, University Of Cincinnati
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Stones, Bones, and Wrecks
Ancient Poop Contains First Evidence of Parasites Described by Hippocrates
Department Of Classics, University Of Cincinnati
Department Of Classics, University Of Cincinnati

The long-held mystery of Hippocrates and the parasitic worms has finally been solved, and it’s all thanks to a few samples of ancient poop.

Researchers don’t know much about the parasites that plagued the Greeks thousands of years ago, and what they do know is largely from the Hippocratic Corpus, the medical texts that the father of medicine and his students put together between the 4th and 3rd centuries BCE. Modern historians have spent years trying to figure out which diseases and parasites Hippocrates and his followers were referring to in their writing, relying solely on their descriptions to guess at what ailments the ancient Greeks might have suffered from. Now, they finally have concrete evidence of the existence of some of the intestinal worms Hippocrates mentioned, Helmins strongyle and Ascaris.

As part of a study in the Journal of Archaeological Science: Reports, an international group of researchers analyzed the ancient remains of feces in 25 prehistoric burials on the Greek island of Kea to determine what parasites the people were carrying when they died. Using microscopes, they looked at the soil (formed by the decomposed poop) found on the pelvic bones of skeletons dating back to the Neolithic, Bronze, and Roman periods.

A roundworm egg under the microscope
A roundworm egg
Elsevier

Around 16 percent of the burials they studied contained evidence of parasites. In these ancient fecal samples, they found the eggs of two different parasitic species. In the soil taken from the skeletons dating back to the Neolithic period, they found whipworm eggs, and in the soil taken from the Bronze Age skeletons, roundworm.

With this information, researchers deduced that what Hippocrates called the Helmins strongyle worm was probably what modern doctors would call roundworm. The Ascaris worm probably referred to two different parasites, they conclude, known today as pinworm (which was not found in this analysis) and whipworm (pictured below).

Whipworm under a microscope
A whipworm egg
Elsevier

Though historians already hypothesized that Hippocrates's patients on Kea had roundworm, the Ascaris finding comes as a particular surprise. Previous research based solely on Hippocrates’s writing rather than physical evidence suggested that what he called Ascaris was probably a pinworm, and another worm he mentioned, Helmins plateia, was probably a tapeworm. But the current research didn’t turn up any evidence of either of those two worms. Instead of pinworm eggs, the researchers found whipworm, another worm that’s similarly small and round. (Pinworms may very well have existed in ancient Greece, the researchers caution, since evidence of their fragile eggs could easily have been lost to time.) The soil analysis has already changed what we know about the intestinal woes of the ancient Greeks of Kea.

More importantly, this study provides the earliest evidence of ancient Greece’s parasitic worm population, proving yet again that ancient poop is one of the world’s most important scientific resources.

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Arctic Temperatures are Rising So Fast, They're Confusing the Hell Out of Computers
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This past year was a brutal one for northern Alaska, which saw temperatures that soared above what was normal month after month. But you wouldn't know that by looking at the numbers from the weather station at Utqiaġvik, Alaska. That's because the recent heat was so unusual for the area that computers marked the data as incorrect and failed to report it for the entirety of 2017, leaving a hole in the records of the Climate Monitoring group at the National Centers for Environmental Information (NCEI), according to the Huffington Post.

The weather station in the northernmost tip of Alaska has been measuring temperatures for nearly a century. A computer system there is programed to recognize if the data has been influenced by artificial forces: Perhaps one of the instruments isn't working correctly, or something is making the immediate area unnaturally hot or cold. In these cases, the computer edits out the anomalies so they don't affect the rest of the data.

But climate change has complicated this failsafe. Temperatures have been so abnormally high that the Utqiaġvik station erroneously removed all its data for 2017 and part of 2016. A look at the region's weather history explains why the computers might have sensed a mistake: The average yearly temperature for the era between 2000 and 2017 has gone up by 1.9°F from that of the era between 1979 and 1999. Break it down by month and the numbers are even more alarming: The average temperature increase is 7.8°F for October, 6.9°F for November, and 4.7°F for December.

"In the context of a changing climate, the Arctic is changing more rapidly than the rest of the planet," Deke Arndt, chief of NOAA's Climate Monitoring Branch, wrote for climate.gov. The higher temperatures rise, the faster Arctic sea ice melts. Arctic sea ice acts as a mirror that reflects the Sun's rays back into space, and without that barrier, the sea absorbs more heat from the Sun and speeds up the warming process. “Utqiaġvik, as one of a precious few fairly long-term observing sites in the American Arctic, is often referenced as an embodiment of rapid Arctic change,” Arndt wrote.

As temperatures continue to grow faster than computers are used to, scientists will have to adjust their algorithms in response. The team at NCEI plans to have the Utqiaġvik station ready to record our changing climate once again within the next few months.

[h/t Huffington Post]

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