Tag Archives: wings

Caudipteryx robot.

Feathered dinosaurs may have accidentally developed flying — while running

Flying is a pretty nifty way of moving around very fast. New research is looking into the dinosaurs’ earliest attempts at flight, an effort which ultimately led to the birds of today.

Caudipteryx Hendrickx.

Reconstruction of Caudipteryx Hendrickx at the Sauriermuseum of Aathal, Switzerland.
Image credits Christophe Hendrickx.

Two-legged dinosaurs likely started dabbling in active flight while running, new research reveals. The findings provide new insight into how these reptiles evolved the ability to fly, a debate that’s been raging ever since 1861 and the discovery of Archaeopteryx. The results point to an alternative evolutionary path that didn’t rely on an intermediate gliding phase, suggesting that the two types of flight have different origins.

Dinos of a feather flap their wings together

“Our work shows that the motion of flapping feathered wings was developed passively and naturally as the dinosaur ran on the ground,” says lead author Jing-Shan Zhao of Tsinghua University, Beijing. “Although this flapping motion could not lift the dinosaur into the air at that time, the motion of flapping wings may have developed earlier than gliding.”

To the best of our knowledge, dinosaurs perfected gliding-type flight much earlier than active flight. The sensible assumption, then, would be that active flight developed from gliding — the two are very similar, mechanically. However, Zhao and his colleagues weren’t convinced. The team studied Caudipteryx, the most primitive non-flying dinosaur known to have had feathered “proto-wings.” It weighed around 5 kilograms, very little for a dinosaur, and looked like a miniature, feathered, beaked T-Rex.

The first part of the research revolved around understanding how Caudipteryx moved about. Using a mathematical approach called modal effective mass theory, the team looked at how the various parts of this dinosaur’s body fared during running, how they moved, and what mechanical forces they were subjected to. From these calculations, the team estimates that running speeds between about 2.5 to 5.8 meters per second would have created forced vibrations that caused the Caudipteryx’s wings to flap. So far, so good — previous research has estimated that Caudipteryx could reach running speeds of up to 8 meters per second, so it could easily achieve the speed interval calculated by the team.

Caudipteryx robot.

Caudipteryx robot used in the tests.
Image credits Talori et al., (2019), PLOS.

Then came the fun part: in order to check their results, the team constructed a life-sized robot Caudipteryx and made it run at different speeds. This step confirmed the initial findings — running motions in the 2.5 to 5.8 meter per second range caused a flapping motion of the wings. To double-double check the results, the team also fitted artificial wings on a young ostrich. Here too, running caused the wings to flap. Longer and larger wings providing a greater lift force, the team notes.

So the first part of this hypothesis seems to pan out. Zhao says that the next step is to analyze the lift and thrust of Caudipteryx’s feathered wings during the passive flapping process, to see if the animal could actually sustain flight over meaningful distances, or just tended to hop around.

The paper “Identification of avian flapping motion from non-volant winged dinosaurs based on modal effective mass analysis” has been published in the journal PLOS Computational Biology.

Wings

CRISPR was used to change a butterfly’s wing color

Butterflies have complex color and scale patterns that allow them to camouflage, attract mates, or warn predators. Researchers used CRISPR/Cas9 to study the genes of one butterfly species to see how they contribute to the wing color and scale structure. Surprisingly, they found that the scale and color of the wings are linked to the same genes.

Wings

The wings of each melanin gene mutant.
image credits

The squinting bush brown butterfly, Bicyclus anynana, comes from East Africa and is typically a dark brown color. A postdoctoral fellow at the National University of Singapore, Yuji Matsuoka, disabled five of the butterfly’s pigment genes with CRISPR/Cas9. CRISPR is a new gene editing system that is capable of adding and disabling genes to different organisms easily and cheaply. The mutations not only changed the color of the butterfly to a light brown/yellow, but also altered the wing scale structure.

“Our research indicates that the color and structure of wing scales are intimately related because pigment molecules also affect the structure of scales,” says senior author Antónia Monteiro, a biologist at the National University of Singapore’s Faculty of Science and Yale-NUS College in Singapore. “Some end products of the melanin pathway, which produces butterfly wing pigments, play a role in both scale pigmentation and scale morphology.”

One mutation prevented the manifestation of the pigment dopa-melanin and it also caused an extra sheet of chitin to form horizontally on the upper surface of the wing scale. However, when the different pigment dopamine-melanin was mutated, there were suddenly vertical blades of chitin. This work shows that butterfly color and scale structure are intimately linked and seem to work together. These fives genes could constrain the evolution of a butterfly’s color.

The wildtype butterfly (left) and with mutations (right).
Image credits: William H. Piel and Antónia Monteiro.

The morphology of wing scales is very different between butterfly species. Melanin seems to be an important molecule in this process and it is likely not the only one. These results also help us to know more about the development and evolution of butterfly wing scales.

“Some butterflies can have vivid hues just by having simple thin films of chitin on their scales that interfere with incoming light to create shades known as structural colors without producing corresponding pigments,” says Monteiro. “Light beams reflecting off the top and bottom surfaces of the chitin layer can interfere with each other and accentuate specific colors depending on the thickness of the film, so our results might be interesting in this context.”

One interesting application of this result could be to bioengineer bright colors based on butterfly scales in the future. Above all, this discovery helps us to better understand butterfly coloration and wing scale structure.

Journal reference: Matsuoka et al. 2018. Melanin Pathway Genes Regulate Color and Morphology of Butterfly Wing Scales. Cell Reports.

NASA Explores the Use of Robotic Bees on Mars

Graphic depiction of Marsbee - Swarm of Flapping Wing Flyers for Enhanced Mars Exploration. Credits: C. Kang.

Graphic depiction of Marsbee – Swarm of Flapping Wing Flyers for Enhanced Mars Exploration. Credits: C. Kang.

Robot bees have been invented before, but Mars might be a place for them to serve a unique purpose. Earlier this year, it was revealed that the Japanese chemist Eijio Miyako led a team at the National Institute of Advanced Industrial Science and Technology (AIST) in developing robotic bees. So they’re not really bees; they’re drones. Miyako’s bee drones are actually capable of a form of pollination similar to real bees.

Bees have been the prime subject of many a sci-fi films including The Savage Bees (1976), The Swarm (1978), and Terror Out of the Sky (1978). In the 21st century, bees have been upgraded. Their robotic counterparts shall have an important role to play in future scientific exploration. And this role could very well be played out on the surface of Mars.

Now, NASA has begun to fund a project to create other AI-steered robotic bees for the future exploration of Mars. The main cause of experimenting with such mini robots is for the desirable need for speed. The problem is this: the traditional rovers sent to Mars in the past move very slowly. NASA anticipates an army of fliers to move significantly faster than their snail-like predecessors.

A number of researchers in Alabama are currently collaborating with a group based in Japan to design these mechanical drones. Sizewise the drones are very similar to real bees; however, the wings are unnaturally large. The lengthened wingspan was a well-needed feature to add since the Red Planet’s atmosphere is thinner compared to Earth’s. These small insect-like robots have been dubbed “Marsbees.”

If used, the Marsbees would travel in swarms and be able to return to some sort of a base, not unlike the way bees return to their hive. The base would likely be a rover providing a place for the Marsbees to be reenergized. But they would not have to come to this rover station to send out the information they’ve accumulated. Similar to satellites, they would be able to transmit their findings wirelessly. Marsbees would also likely be able to collect a variety of data. If their full development is feasible and economical, the future for Marsbees looks promising.

How butterflies have such a beautiful colour

Butterflies are some of the most exquisitely patterned and coloured creatures in the world. The colours all start with the scales on their wings. The scales contain crystals called gyroids that are made of chitin, the substance that is also in insect exoskeletons. These structures are complex and just a few nanometers large — so extremely tiny. Nanotechnology, creating tiny structures for industry, also creates such small-scale structures. They are important in areas such as medicine, electronics, and space travel. However, the nanostructures on butterfly wings are way more complex than anything that can be man-made. A group of researchers examined how the crystals develop on a butterfly’s wing for potential uses in industry.

The small Hairstreak. Image credits: Wilts et al., 2017.

The study that is published in Science Advances set out to discover how these crystals that give butterflies their magnificent colour form. It isn’t yet possible to study a butterfly’s wing while it’s developing, so the researchers examined the scales of a grown butterfly under extreme magnification. The subject? The small Hairstreak butterfly Thecla opisena from Mexico. The upper side is jet-black with blue patches while the lower side is green with a small red patch on the bottom edge of the wing. However, if you zoom into the bright green wing it’s actually not all green. The cover scales are bright green while the background is an orange-red colour. The cover scales themselves are not completely green but are made up of several domains that don’t overlap.

A close-up of one wing scale wing; it has a red background with green domains on top. Image credits: Wilts et al., 2017.

Each scale contains structured nanocrystals that interestingly, were spatially separated and loosely connected to the lower surface of the wing. On the wing, the crystals were arranged in lines, and at the beginning of the line the crystals were really small but as you progress further down the line, the crystals get larger. Perhaps, the scales form this way and are constantly growing on the wing. They seem to be developmental stages frozen in time and show the process of how these crystal form. The way that the scales develop is likely that the casing forms first and then the internal gyroid structure follows.

How the crystals develop over time. Image credits: Wilts et al., 2017.

We do need to keep in mind that this is just one butterfly out of more than 140,000 species. However, it is likely, according to the authors, that this way of development can be generalised to most wing scales and that all butterflies get their colour in a similar way. They could be very useful for nanotechnological applications, such as light-guiding technology because they can manipulate light in arbitrary directions. It is interesting to see how the natural world inspires technological advances.

Journal reference: Wilts, B.D. et al., 2017. Butterfly gyroid nanostructures as a time-frozen glimpse of intracellular membrane development, Science Advances.

Amazing wing tips trapped in amber for 100 million years. Credit: RYAN C. MCKELLAR

Dino bird wings found in fossilized 100-million-year-old amber look simply stunning

Amazing wing tips trapped in amber for 100 million years. Credit: RYAN C. MCKELLAR

Amazing wing tips trapped in amber for 100 million years. Credit: RYAN C. MCKELLAR

Two stunning bird wings were found by paleontologists trapped in 100-million-year-old amber. The specimens discovered by the researchers are one of a kind and, unlike previous amber fossils, the feathers were attached to tissue, too.

The mid-Cretacious fossils were found in a Burmese amber deposit, where many ancient insects, plants and animals became trapped in resin, sealed against time for millions of years.

Another closeup. Credit: RYAN C. MCKELLAR

Another closeup. Credit: RYAN C. MCKELLAR

The mummified wings in question likely belonged to enantiornithes, avian dinosaurs which became extinct at the end of the Cretacious.

While it’s generally agreed that virtually all dinosaurs had feathers, scientists have to base their conclusions on findings that tell very little. The few dinosaurs that became fossilized feathers and all, like the famous Archaeopteryx, only provide a 2-D picture with no depth — besides they’re also rare.

This sample was nicknamed "Angel". Credit: RYAN C. MCKELLAR

This sample was nicknamed “Angel”. Credit: RYAN C. MCKELLAR

The two dinosaur-era bird wings, however, come complete with bone, skin, muscle, tissue and tracts of feathers — all still intact.

“The biggest problem we face with feathers in amber is that we usually get small fragments or isolated feathers, and we’re never quite sure who produced [them],” says co-author Ryan McKellar, curator of invertebrate palaeontology at Canada’s Royal Saskatchewan Museum. “We don’t get something like this. It’s mind-blowingly cool.”

CT scans show the wings likely belonged to juveniles, judging from the bone size that suggests early development. Amazingly, feathers from 100 million years ago weren’t all that different from those sported by modern birds. The similarities include pigmentation, wing arrangement or microstructure.

The findings are even more amazing once you realize the 100-million-year-old bird wings could have been turned into trinkets. Burmese amber is famous for its many artifacts, which often get sold in flee markets like dime a dozen retail goods. Many locals illegally go into mines in search for amber fossils to make their living. The smaller of the two samples was initially destined to become part of a jewelry piece called “Angel’s Wings”, but luckily scientists procured it in time from a Myanmar amber market. The sample has been nicknamed “Angel” since. Who knows what inestimable treasures still lie around these markets.

“About 70 percent of the Burmese amber is barren, but the other 30 percent features phenomenal biodiversity,” said David Grimaldi, curator of invertebrate zoology at the American Museum of Natural History.. “Never, ever would I have predicted this level of diversity.”