New Delhi: Scientists have discovered a new asteroid that orbits the Sun once every 113 days, making it the asteroid with the shortest known orbital period.
The asteroid, named 2021 PH27, has the second shortest orbital period for any object in our Solar System, after Mercury, which has an orbital period of just under 88 days.
The asteroid is about 1 kilometer in diameter, and was discovered in evening twilight images taken by researchers at Brown University.
Researchers said that it is on an unstable orbit, that crosses the paths of Mercury and Venus. This means that within a few million years it will likely be destroyed in a collision with one of these planets or the Sun, or it will be removed from its current position.
Studying objects like this can help scientists understand where asteroids originated and the forces that shaped the architecture of our Solar System.
An object like 2021 PH27 experiences tremendous thermal and internal stresses due to its proximity to the Sun. Comparing 2021 PH27 to objects that orbit beyond Earth will improve researchers’ knowledge of its composition and the materials that enable its survival under these extreme conditions. Read more.
Confiscated Brazil fossil is a rare specimen of pterosaur
A fossil that had been confiscated during a police raid in Brazil turned out to be that of a rare specimen – one of the best-preserved flying reptiles ever found – after scientists studied it for nearly five years.
In 2013, smugglers in São Paulo were about to ship a cache of fossils out of the Santos Harbor. But the local police foiled their attempt. Among the recovered fossils, were six large slabs of limestone.
Preserved across these slabs was specimen of a subgroup of flying reptiles called pterosaurs, also known as Tapejarids.
These reptiles had enormous head crests. There are abundant pterosaur fossils in Brazil, but most of these preserve only partial remains.
By reuniting the slabs researchers were able to examine the entire fossil, even CT-scanning to reveal the bones concealed within the stone.
The specimen has nearly the entire body, including remnants of soft tissue alongside the bones, making it the most complete tapejarid skeleton ever found in Brazil.
The species is called Tupandactylus navigans, which had likely had a terrestrial foraging lifestyle.
However, the specimen has all the necessary adaptation to enable it to fly. Further studies will help better understand the lifestyle of this fossil. Read more.
Female hummingbirds use colours to avoid male harassment
Scientists have found that female of the human species may not be the only ones to have to find ways to avoid harassment from the males of the species.
It seems young female hummingbirds have evolved in a way to disguise themselves as males, in order to avoid aggressive male behavior during feeding, such as pecking and body slamming.
The researchers observed white-necked Jacobin hummingbirds in Panama and found that over a quarter of females have the same brightly colored ornamentation as males.
For birds, it is unusual for female juveniles to look like adult males.
Male white-necked Jacobin hummingbirds are known to have bright and flashy colors, with blue heads, bright white tails, and white bellies.
Female Jacobins, on the other hand, tend to have muted green, gray, or black colors that allow them to blend into their environment.
To learn why some female hummingbirds had the showy colors that usually characterise the male of the species, the researchers set up a scenario with stuffed hummingbirds on feeders and watched as real hummingbirds interacted with them.
They found that hummingbirds harassed mainly the muted colored female hummingbirds, which is in favor of the hypothesis that the showy colors are caused by social selection. Furthermore, most females had showy colors during their juvenile period and not during their reproductive period.
This means that the only time they had flashy colors is precisely during the period when they’re not looking for mates. Read More.
Madagascar faces world’s first climate change famine
The United Nations (UN) this week said that Madagascar may be facing what would be the world’s first “climate change famine”.
According to the UN, tens of thousands of people are already suffering hunger and food insecurity, after the country went without rain for four years .
The drought is the worst recorded in four decades.
The famine-like conditions are being driven by climate, rather than conflict, according to a UN World Food Programme spokesperson, leaving families to survive on insects.
The UN estimates that 30,000 people are currently experiencing the highest internationally recognised level of food insecurity. The numbers could rise further. Read More.
DNA found from teen who died 7,200 years ago in Indonesia
Archeologists have discovered and analysed ancient DNA in the remains of a teenager who lived 7,200 years ago in Indonesia. The findings from the DNA change what we know about migration in the region in ancient times.
The remains, belonging to a teenager nicknamed Bessé, was discovered during excavations in 2015.
It is believed to be the first time ancient human DNA has been discovered in Wallacea, which are the vast chain of islands and atolls in the ocean between mainland Asia and Australia.
Finding ancient DNA in humid tropics is rare because the climate conditions don’t allow remains to be preserved. There are very few skeletons that have yielded ancient DNA in all of mainland south-east Asia.
In colder climates of Europe and America, ancient DNA analysis has helped advance the understanding of early human history.
Researchers found that half of the teen’s genes are similar to the present-day Indigenous Australians and people from New Guinea and the Western Pacific islands.
This suggests that the teen’s ancestors moved from mainland Asia through these Wallacean islands towards Sahul, which was the combined ice age landmass of Australia and New Guinea.
The DNA also showed an ancient link to east Asia, which challenges what was previously known about the timeline of migration to Wallacea.
It suggests some people from Asia migrated into this region much earlier than thought. Read More.
(Edited by Poulomi Banerjee)