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New Species of Alaskan Water Flea Discovered And It’s ADORABLE!!!

26 Mar

New species discovered by scientists in Northwest Alaska

by Doug O’Harra

Scientists have discovered a new variety of water flea in a roadside pond on the Seward Peninsula outside of Nome, suggesting that life in the Alaskan Arctic may be far ecologically mysterious than previously thought.

This tiny crustacean — now named Eurycercus beringi — was identified during a multi-year, trans-continental investigation of water fleas that squiggle through small lakes across Alaska, Siberia and other Northern Hemisphere locales. The creatures fill a niche near the bottom of the freshwater food chain, providing summer food for birds while munching on even smaller life that erupts during the intense, brief Arctic summer.

Among other things, the scientists documented 10 different species of water fleas in these northern ecosystems instead of the two previously thought to live there. That represents a remarkable five-fold increase in water flea diversity in the Far North.

Don’t dismiss these findings, reported Feb. 24 in the journal Zootaxa, as just some arcane taxonomic trivia about weird-looking pond monsters — especially in the face of widespread permafrost melt and climate change.

With summers growing warmer and vegetation shifting, aquatic life unknown to modern science might be squirming incognito off the toes of our XtraTufs in potholes and tundra lakes that have begun to vanish and shrink. As these water bodies drain into the Earth or dry up, their biological treasures could vanish with them.

“It is well known that parts of Alaska and Siberia have suffered a huge reduction in freshwater surface area, with many lakes and ponds disappearing permanently in the past few decades,” explained co-author Derek J. Taylor, a biologist at the University at Buffalo, in this story about the research. “What we’re now finding is that these regions with vanishing waters, while not the most diverse in the world, do contain some unique aquatic animals.”

“Some of these subarctic ponds that water fleas inhabit are held up by permafrost, so when this lining of ice melts or cracks, it’s like pulling the plug out of a sink,” Taylor added. “When you see the crop circle-like skeletons of drained ponds on the tundra you can’t help but wonder what animal life has been lost here.”

Along with Eugeniya I. Bekker and Alexey A. Kotov of the A. N. Severtsov Institute of Ecology and Evolution in Moscow, Taylor concentrated on the quarter-inch-long water fleas from the genus Eurycercus in ponds across the globe. One surprising finding? These particular water fleas appear to be more diverse in northern regions than in the tropics.

“This is a counterintuitive concept, as scientists have long supposed that the advance and re-advance of ice sheets reduced much of the species diversity in colder climates,” Taylor explained in this story. “However, there is growing evidence that some northern areas remained ice-free and acted as hideouts during the harsh glacial advances.”

Contact Doug O’Harra at doug(at)alaskadispatch.com

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Microscopy Monday {No.3}

26 Mar

Immature sperm in the spermatocyte stage of the crane flyNephrotoma suturalis. (60x)

Image by Rudolf Oldenbourg.

Outside Ovaries

24 Mar

The following is written by Michael Marshall of New Scientist

First Animal With Ovaries On The Outside

SpeciesAllapasus aurantiacus
Habitat: On and around the seabed off the coast of California

If there’s one way we can be sure that life on Earth really is the result of evolution, and not the guiding hand of a cosmic engineer, it’s the hideous design flaws. The examples are too numerous to list, but let’s just consider one: human males have their testicles on the outside.

It seems they work better that way, because sperm production works best slightly below human body temperature. But it isn’t half inconvenient – as any male who has ever been kicked in the goolies will tell you.

Spare a thought, then, for the newly-discovered acorn worm Allapasus aurantiacus. The females are the first animals known that have their ovaries on the outside. But according to their discoverers, they are the first of many.


(The best shot starts at the 20 second mark)

Deep-sea worms

Acorn worms are quite different to the more familiar annelid worms, as they are close-ish relatives of backboned animals. They live on the sea bed, often burrowing into the sediment.

No one had noticed A. aurantiacus until June 2002, when Karen Osborn of the Smithsonian Institution in Washington, DC spotted one via a remotely-operated vehicle deep into the Monterey Submarine Canyon off California, around 3000 metres down. Intrigued, she had it brought to the surface.

Once Osborn got a closer look she realised it was an acorn worm. Unusually large eggs, each almost 2 millimetres across, were pouring out of it. The new species belonged to a family of acorn worms called Torquaratoridae, which all live in the deep sea – unlike many acorn worms, which prefer the shallows.

Ovaries on display

Each worm has two “wings” – flaps of skin on the main body along much of its length. In an unprecedented arrangement, the ovaries are attached to the inner surfaces of these wings.

“Usually you want to protect these things, and keep them near and dear,” Osborn says. Even human testicles have several layers of skin protecting them. But the eggs of A. aurantiacus are only protected by a single layer of cells. That might make it easier for sperm to reach them, Osborn says.

She has since found a few males, whose genitals are in the same place on their skin. It’s not clear how they fertilise the females’ eggs. One possibility is that the males release sperm into the water, whereupon the females take it in through their gills and squirt it over the ovaries – which are ideally placed by the gill outlets.

Floating free

The worm uses its wings as sticky pads to attach itself to the sea floor. “They secrete a ton of mucus, and that probably helps them adhere,” Osborn says. “Mucus is a big part of their lives.”

Mucus may also be the key to the worm’s ability to float above the sea bed – something that only the deep-sea acorn worms do. Osborn thinks they secrete a balloon of mucus around themselves, which catches currents that then carry the worm away.

But first they have to get off the sea bed, and to do that they excrete the contents of their guts. This material acts as ballast, so getting rid of it means they drift upwards.

First of many

Osborn and her colleagues have since found over a dozen acorn worms in the same family. They all have external ovaries and the distinctive wings. One species has hermaphrodite forms, another first for acorn worms.

Worms aren’t known for their parenting skills but in a further surprise, at least one species uses the wings to shelter its offspring. Osborn found a single female, of a species closely related to A. aurantiacus, that was sheltering well-developed eggs and a few larvae under its wings.

She suggests that the acorn worms’ strange lifestyles are adaptations to life on the sea floor, where food and mates are scarce. In a place like that, it makes sense to move around in search of new feeding grounds, to make use of any and all sperm that comes your way, and to keep your young close until they’re ready to take care of themselves.

Journal reference: Journal of Morphology, DOI: 10.1002/jmor.20013

Extract Your Own DNA

21 Mar

As a promotion for their upcoming show “Cracking The Genetic Code,” NOVA released this short video showing you how to extract your own DNA using common household items. I’ve done this before with dozens of little kids, using the Gene In A Bottle kit, available from Bio-Rad. It’s a great fundraiser, simple to do, and very safe. They absolutely love it, and it’s a great science activity the family can do at home. Just don’t let those devious teenagers try to go off and clone themselves.

“Cracking The Genetic Code” airs next Wednesday, March 28th, on PBS. Don’t miss it!

Hugs

19 Mar


 It’s a scientific fact that hugs are what keeps us alive.

More cute drawings can be found at I Love Doodle

Microscopy Monday {No.2}

19 Mar

Cells from the trabecular meshwork of a pig’s eye. The trabecular meshwork assists in draining the aqueous humor, the fluid between the lens and the cornea, (20x)

Image by Carmen Laethem, Aerie Pharmaceuticals.

Drunken Fruit Flies

18 Mar

The Internet has been abuzz the past few days with news of fruit flies turning to booze when denied sex. Here’s a delightful piece posted on NPR a few days ago covering the subject. It should be noted that fruit flies are insanely awesome and one of the most commonly used specimens in scientific research, especially genetic research.

When Fruit Flies Strike Out, They Like To Booze It Up


By Scott Hensley of NPR

Have pity on these poor fruit flies.

Researchers made a bunch of male fruit flies into boozehounds by pushing them on females unreceptive to their advances.

After a few days of striking out, the male losers, referred to as the “rejected-isolated” group in a study published online by Science, drowned their sorrows in alcohol.

They preferred food spiked with ethanol to their regular meal, and they were more likely to go for the alcohol than the males who’d had sex.

It’s a sad experiment. And one that many of us have been subjected to in real life.

But this work conducted at the University of California, San Francisco, revealed more than that an age-old melodrama could be played out by fruit flies. The researchers showed that a chemical called neuropeptide F in the flies’ brains played a key role in determining their behavior.

The less neuropeptide F was present in their little fly brains, the more likely they were to seek a drink. Being denied sex lowered neuropeptide F and increased their self-medication.

But there’s a solution, and the researchers write dryly about it:

[T]he effects of sexual deprivation can be reversed by copulation, which is consistent with sexual deprivation being the major contributor to ethanol preference.

So having sex boosted neuropeptide F, decreasing the flies’ interest in alcohol.

Very interesting for flies, you might say. So what?

Well, it turns we humans aren’t sooooo different.

Humans’ brains have got the same sort of chemical, called neuropeptide Y in our case, and it also looks like an important ingredient when it comes to our internal reward systems.

In humans, neuropeptide Y may be important in regulating stress and anxiety. When the chemical is out of whack, it may contribute to addictive behavior.

The experiments in flies show how social experiences may shape chemical dependence through changes in the level of neuropeptides.

Don’t expect a drug or treatment for people based on neuropeptides anytime soon. It’s not easy to get a molecule like that inside someone’s brain, even if the science someday suggests that might be truly helpful.

Still, there have been some early experiments with neuropeptide Y, including one using it in a nasal spray as a potential treatment for post-traumatic stress disorder.