New Delhi: Researchers have discovered a trove of marine life hidden far beneath the ice shelves of the Antarctic. Despite occupying nearly 1.6 million square kilometres, ice shelves are among the least explored environments on Earth. Life has been seen in these perpetually dark and cold habitats on camera, but has rarely been collected.
Using hot water, a team of researchers from Germany drilled two holes, through nearly 200 metres of the Ekström Ice Shelf in the southeastern Weddell Sea in 2018. The environment is harsh and extremely cold, with temperatures dropping to minus 2.2 degrees Celsius.
Despite being several kilometres from the open sea, the biodiversity of the specimens they collected was extremely rich. The researchers said that it is richer than many open water samples found on the continental shelf where light and food sources are present.
The team discovered 77 species — including sabre-shaped bryozoans (moss animals) and serpulid worms — more than the total number previously known from all the frozen continent’s ice shelves.
The team concludes that there must be enough algae carried under the ice shelf from open water to fuel a strong food web. Microscopy of samples showed that, surprisingly, the annual growth of four of the species was comparable with similar animals in open marine Antarctic shelf habitats.
The team also notes that with climate change and the collapse of these ice shelves, time is running out to study and protect these ecosystems. Read more
New muscle discovered in the human jaw
Researchers at the University of Basel have discovered a previously overlooked section of our jaw muscles and described this layer in detail for the first time.
The masseter muscle is the most prominent of the jaw muscles. If you place your fingers on the back of your cheeks and press your teeth together, you’ll feel the muscle tighten. Anatomy textbooks generally describe the masseter as consisting of one superficial and one deep part.
Now, researchers have described the structure of the masseter muscle as consisting of an additional third, even deeper layer. They propose that this layer be given the name Musculus masseter pars coronidea, which means the coronoid section of the masseter.
The anatomical study was based on detailed examination of formalin-fixed jaw musculature, CT scans and the analysis of stained tissue sections from deceased individuals who had donated their bodies to science. This was in addition to MRI data from a living person.
The structure of the masseter muscle has already raised questions in the past. In a previous edition of Gray’s Anatomy, from the year 1995, the editors also describe the masseter muscle as having three layers, although the cited studies were based on the jaw musculature of other species and partly contradict one another. Read more
Rare dinosaur embryo discovered in China
In a first, scientists have discovered a rare fossil of a well-preserved dinosaur embryo in southern China.
While many fossilised dinosaur eggs and nests have been found over the last century, finding one with a well-preserved embryo inside is exceedingly rare.
By analysing the fossil, researchers found that oviraptorosaurs — a group of therapods closely related to birds — took on a distinctive tucking posture before they hatched, a behaviour that had been considered unique to birds.
It raises the possibility that tucking behaviour may have evolved first among non-avian theropods during the Cretaceous period.
Usually, dinosaur embryos are incomplete with skeletons scattered, which is why the team was surprised to see this embryo preserved inside a dinosaur egg, lying in a bird-like posture. This posture had not been recognised in non-avian dinosaurs before.
It had been acquired by a Chinese museum in 2000, but it then ended up in storage, largely forgotten until about 10 years later, when museum staff sorted through the boxes and unearthed the fossils.
The notion that such pre-hatching behaviour may have originated among non-avian theropods can now be further investigated through more studies of other fossil embryos. But first, the researchers say they’ll continue studying this rare specimen in even more depth, using various imaging techniques to image its internal anatomy, such as skull bones, and other body parts that are still covered in rocks. Read more
Violent pulses from a neutron star captured for the first time
Scientists have for the first time managed to measure the oscillations in the brightness of a neutron star known as a magnetar during its most violent moments.
In just a tenth of a second, the magnetar released energy equivalent to that produced by the Sun in 100,000 years.
Neutron stars are objects that can contain half a million times the mass of the Earth in a diameter of about 20 kilometres. Magnetars are a type of neutron star that have the most intense magnetic field known.
The observation was carried out automatically using an artificial intelligence system developed at the University of Valencia.
Magnetars suffer violent eruptions that are still little known due to their unexpected nature and their duration of barely tenths of a second. Detecting them is a challenge for science and technology as only 30 magnetars have been discovered so far.
But researchers have managed to measure pulses in the brightness of the magnetar during its most violent moments. These episodes are a crucial component in understanding giant magnetar eruptions that have been debated during the past 20 years. Read more
Scientists design hovering rover for the Moon
Scientists at MIT have designed a hovering rover that can explore the Moon and other such airless cosmic bodies.
The rover works by harnessing the Moon’s natural charge. Due to the lack of an atmosphere, the Moon and other cosmic bodies can build up an electric field through direct exposure to the sun and surrounding plasma.
On the Moon, this surface charge is strong enough to levitate dust more than one metre above the ground — just like how static electricity can cause a person’s hair to stand on end.
Researchers have proposed harnessing this natural surface charge to levitate a glider with wings made of Mylar, a material that naturally holds the same charge as surfaces on airless bodies. They reasoned that the similarly charged surfaces should repel each other, with a force that takes the glider off the ground.
But such a design would likely be limited to small asteroids, as larger planetary bodies would have a stronger, counteracting gravitational pull.
The MIT team’s levitating rover could potentially get around this limitation.
The concept uses tiny ion beams to both charge up the vehicle and boost the surface’s natural charge. The overall effect is designed to generate a relatively large repulsive force between the vehicle and the ground, in a way that requires very little power.
In an initial feasibility study, the researchers show that such an ion boost should be strong enough to levitate a small, two-pound vehicle on the Moon and large asteroids like Psyche. Read more
(Edited by Rohan Manoj)