Polar bears hunt without ice, insect 'honeydew' has antioxidants, and three theories about what causes long COVID

Good Morning!

NASA is closing in on launch readiness for its large Space Launch System rocket with a wet-dress rehearsal test to within just 29 seconds before liftoff. While we wait, read on about polar bears without sea ice, antioxidant honeydew, and COVID brain fog.

The world’s largest gliding marsupial, the Greater Glider in Australia, easily overheat without access to cool tree hollows. Unfortunately, the Greater Glider has lost tons of its valuable tree habitat to bush fires and logging. Now, manufactured high-tech nest boxes with insulation may help this “clumsy possum” recover.

Innovative polar bear population can hunt without sea ice

Given their dependence on sea ice platforms as launch pads from which to hunt seals, polar bears (Ursus maritimus) are vulnerable to the changing climate. They typically hunt by sniffing out seals and waiting for them (days or weeks) to come up for air, then pouncing. As sea ice melts, polar bears are finding themselves… on thin ice.

However, a new study describes a polar bear population in Southeast Greenland where there’s only sea ice during about 100 days of the year. In their isolated fjord habitat, this special sub-population has nevertheless managed to hunt. They use the glacial-freshwater mélange, the scrappy stuff at the end of glaciers, as their hunting grounds.

These innovative bears provide a glimmer of hope about how polar bears will weather climate change. Said study author Kristin Laidre, “This small, genetically distinct group of bears could shed light on how polar bears as a species might persist in an ice-free Arctic.”

It's called fashion, sweetie

New hairy species of crab rocks a sponge hat

A group of crabs in the family Dromiidae are known for their habit of carrying sponges around, thus their moniker “sponge crabs.” Fine hairs on their hard outer exoskeleton act as little hooks that snag bits of living materials like sponges and tunicates. While they have to redo their accessories every time they molt, the overall ensemble protects the crabs by conferring camouflage and chemical defenses from the sponges.

Now, a species of sponge crab new to science shows the extreme of what’s possible in sponge-wear. Named after Darwin’s HMS Beagle ship, the Lamarckdromia beagle specimen is extremely hairy and sports a sponge atop its head like a cap.

According to study author Andrew Hosie, "All members of this group of crabs are hairy to some extent, but this one is ridiculous. We can't really give a definitive answer as to why… we suspect it's to help further camouflage its legs from predators."

With more than 30 species of sponge crab known along Australia’s coast, even weirder ones may surface in the future.

'Honey' from insect waste has antioxidant properties

We may take honey for granted, but not all honey is created alike. Bees make honey from the nectar of wildflowers, avocados, orange blossoms, and—for the coveted medicinal Manuka honey—from tea trees. Perhaps the most unfamiliar variety, however, is honeydew honey, made from insect waste.

This rare honey is produced when scale insects suck the sap out of beech trees, then exude sticky honeydew from their rear ends that bees consume and convert into honey.

A new study examined the chemistry of the dark brown honeydew honey and found it to have potent antioxidant properties. Said study authors, “The antioxidant activity of New Zealand honeydew honey is comparable to several studies on Manuka honey, which is widely considered as the ‘gold standard’ for its antioxidant activity.”

The researchers expect the demand for honeydew honey to grow as people discover its antimicrobial and anti-inflammatory properties. And another study reported that honeydew might be useful in plant pest control via the bacteria that it supports. So, watch for a run on honeydew.

Known by many names, long COVID (post-acute COVID, chronic COVID) is unfortunately also known to many people. The U.S. Government Accountability Office estimates people suffering from long COVID at 7.7 – 23 million. In late 2021, the World Health Organization defined long COVID as the “constellation of long-term symptoms” suffered by “long-haulers.”

“Every person on average has, like, 16 or 17 symptoms,” says neuroscientist Athena Akrami. These symptoms range from exhaustion and confusion to joint and muscle pain, sleep disturbances, mood changes, hallucinations—even heart attack or stroke. The risk of cardiac problems soars by 72% after even a mild case of COVID, irrespective of age or risk factors. But one of the most distressing aspects is the brain fog that leaves people with memory lapses.

A recent study imaged the brains of more than 400 people, aged 51 to 81, who had contracted COVID-19, compared to those who had not. The data revealed reduction in brain gray matter, primarily in the limbic (emotions and memory) and olfactory (sense of smell) areas, adding up to reduced brain size.

And another study found similarities to brains impacted by neurodegenerative diseases – Alzheimer’s or Parkinson’s. Said study author Nick Reynolds, “What we saw is...ordered assemblies of protein considered ‘molecular hallmarks’ of the early stages of neurodegenerative disease.”

But why these chilling outcomes? Ongoing research reveals several possible causes of the impacts to brains and other body organs.

For one, fragments of virus may linger in your body long after you’re infected. Two recent studies showed that persistent vomiting and diarrhea in people who’d had the virus stemmed from pieces of SARS-CoV-2 hanging out in the gut for months. These “coronavirus ghosts” could explain why long COVID sufferers have problems with multiple body organs.

Another cause could be your immune system going haywire and attacking body tissues. “SARS-CoV-2 is like a nuclear bomb in terms of the immune system,” said infectious disease researcher Steven Deeks. There’s evidence that the virus triggers an auto-immune disorder, in which ”autoantibodies” go rogue and damage organs. The phenomenon is not unprecedented—other viruses such as Epstein-Barr (the virus that causes mono) are also implicated in autoimmune illnesses.

There’s also emerging evidence from children and adults with long COVID that tiny blood clots or damage to blood vessel linings impair blood flow to their lungs.

People have staked their hopes on vaccines to prevent long COVID symptoms even after breakthrough infections. Results are mixed, but a recent study with the biggest sample to date (over 13 million people) shows that vaccination reduces the likelihood of long COVID by only about 15%. And, unfortunately, reports of brain fog and fatigue were similar for vaccinated and unvaccinated study subjects who’d had the virus.

So, the medical community is in an uphill battle to answer urgent questions that will help long COVID sufferers. In the meantime, avoiding the virus has the best outcomes.

An underwater encounter with a beautiful and unusual "feather star".
This video gives rare glimpse of weather balloon exploding 20 miles above Earth.
The world's biggest freshwater fish ever recorded—what a catch.
"The Incredible Journey of Three African Wild Dogs"

Next time we’ll be taking a dive into some unexpected artifacts that have been hiding underwater.

MEME OF THE WEEK

Written by Devin Reese, Edited by Jake Currie

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