Enlarge / A time-lapse showing how an insect's wing adopts very specific positions during flight. (credit: Florian Muijres, Dickinson Lab)

About 350 million years ago, our planet witnessed the evolution of the first flying creatures. They are still around, and some of them continue to annoy us with their buzzing. While scientists have classified these creatures as pterygotes, the rest of the world simply calls them winged insects.

There are many aspects of insect biology, especially their flight , that remain a mystery for scientists. One is simply how they move their wings. The insect wing hinge is a specialized joint that connects an insect’s wings with its body. It’s composed of five interconnected plate-like structures called sclerites. When these plates are shifted by the underlying muscles, it makes the insect wings flap.

Until now, it has been tricky for scientists to understand the biomechanics that govern the motion of the sclerites even using advanced imaging technologies. “The sclerites within the wing hinge are so small and move so rapidly that their mechanical operation during flight has not been accurately captured despite efforts using stroboscopic photography, high-speed videography, and X-ray tomography,” Michael Dickinson, Zarem professor of biology and bioengineering at the California Institute of Technology (Caltech), told Ars Technica.

Enlarge (credit: Sergey Krasovskiy )

Blue whales have been considered the largest creatures to ever live on Earth. With a maximum length of nearly 30 meters and weighing nearly 200 tons, they are the all-time undisputed heavyweight champions of the animal kingdom.

Now, digging on a beach in Somerset, UK, a team of British paleontologists found the remains of an ichthyosaur, a marine reptile that could give the whales some competition. “It is quite remarkable to think that gigantic, blue-whale-sized ichthyosaurs were swimming in the oceans around what was the UK during the Triassic Period,” said Dr Dean Lomax, a paleontologist at the University of Manchester who led the study.

Giant jawbones

Ichthyosaurs were found in the seas through much of the Mesozoic era, appearing as early as 250 million years ago. They had four limbs that looked like paddles, vertical tail fins that extended downward in most species, and generally looked like large, reptilian dolphins with elongated narrow jaws lined up with teeth. And some of them were really huge. The largest ichthyosaur skeleton so far was found in British Columbia, Canada, measured 21 meters, and belonged to a particularly massive ichthyosaur called Shonisaurus sikanniensis . But it seems they could get even larger than that.

Enlarge / SEM Micrograph of a tardigrade, more commonly known as a "water bear" or "moss piglet." (credit: Cultura RM Exclusive/Gregory S. Paulson/Getty Images)

Since the 1960s, scientists have known that the tiny tardigrade can withstand very intense radiation blasts 1,000 times stronger than what most other animals could endure. According to a new paper published in the journal Current Biology, it's not that such ionizing radiation doesn't damage tardigrades' DNA; rather, the tardigrades are able to rapidly repair any such damage. The findings complement those of a separate study published in January that also explored tardigrades' response to radiation.

“These animals are mounting an incredible response to radiation, and that seems to be a secret to their extreme survival abilities,” said co-author Courtney Clark-Hachtel , who was a postdoc in Bob Goldstein's lab at the University of North Carolina at Chapel Hill, which has been conducting research into tardigrades for 25 years. “What we are learning about how tardigrades overcome radiation stress can lead to new ideas about how we might try to protect other animals and microorganisms from damaging radiation.”

As reported previously , tardigrades are micro-animals that can survive in the harshest conditions: extreme pressure, extreme temperature, radiation, dehydration, starvation—even exposure to the vacuum of outer space. The creatures were first described by German zoologist Johann Goeze in 1773. They were dubbed tardigrada ("slow steppers" or "slow walkers") four years later by Lazzaro Spallanzani, an Italian biologist. That's because tardigrades tend to lumber along like a bear. Since they can survive almost anywhere, they can be found in lots of places: deep-sea trenches, salt and freshwater sediments, tropical rain forests, the Antarctic, mud volcanoes, sand dunes, beaches, and lichen and moss. (Another name for them is "moss piglets.")

Enlarge (credit: OsakaWayne Studios )

As if we didn’t have enough reasons to get at least eight hours of sleep , there is now one more. Neurons are still active during sleep. We may not realize it, but the brain takes advantage of this recharging period to get rid of junk that was accumulating during waking hours.

Sleep is something like a soft reboot. We knew that slow brainwaves had something to do with restful sleep; researchers at the Washington University School of Medicine in St. Louis have now found out why. When we are awake, our neurons require energy to fuel complex tasks such as problem-solving and committing things to memory. The problem is that debris gets left behind after they consume these nutrients. As we sleep, neurons use these rhythmic waves to help move cerebrospinal fluid through brain tissue, carrying out metabolic waste in the process.

In other words, neurons need to take out the trash so it doesn’t accumulate and potentially contribute to neurodegenerative diseases. “Neurons serve as master organizers for brain clearance,” the WUSTL research team said in a study recently published in Nature .