New Delhi: While scientists widely believe that a large asteroid that hit Earth nearly 66 million years ago contributed to the global extinction of dinosaurs, new research from China now shows that the prehistoric predators may have already been on a decline much before the incident.
Researchers at the Chinese Academy of Sciences, along with their collaborators, studied over 1,000 fossilised dinosaur eggs and eggshells from the Shanyang Basin in central China.
These fossils came from rock sequences with a total thickness of about 150 metres. The researchers obtained detailed age estimates of the rock layers by analysing and applying computer modelling to over 5,500 geological samples.
This allowed the scientists to create a timeline of nearly two million years at the end of the Cretaceous period representing the period right before extinction. This timeline allows direct comparisons with data from around the world.
The data showed that dinosaurs were probably already declining globally before the fateful asteroid impact resulted in their extinction.
The researchers suggest that their decline may have resulted from known global climate fluctuations and massive volcanic eruptions such as those in the Deccan Traps in what is now India. Read more
New research shows Saturn’s moon may have all the essential ingredients for life
Scientists at the Southwest Research Institute in the US have discovered new evidence for a key building block of life in the subsurface ocean of Saturn’s moon Enceladus — indicating that the planet may have potential to harbour life.
Their research indicates that Enceladus’s ocean should be relatively rich in dissolved phosphorus, an essential ingredient for life.
The research is based on NASA’s Cassini spacecraft’s mission. The spacecraft was deliberately crashed onto the surface of Saturn in 2017 to keep the moons pristine, prior to which it had discovered Enceladus’s subsurface liquid water and flown through the plumes of ice grains and water vapour erupted into space from cracks in the moon’s icy surface.
The team at Southwest Research Institute have been studying Enceladus for years. They found that these plumes contain almost all the basic requirements of life and that while phosphorus is not present directly in the plume, there is evidence for its availability in the ocean beneath its icy crust.
Phosphorus in the form of phosphates is vital for all life on Earth. It is essential for the creation of DNA and RNA, energy-carrying molecules, cell membranes, bones and teeth in people and animals, and even the sea’s microbiome of plankton.
Team members performed thermodynamic and kinetic modelling that simulates the geochemistry of phosphorus based on insights from Cassini about the ocean-seafloor system on Enceladus. They developed a detailed geochemical model of how seafloor minerals dissolve into Enceladus’s ocean and predicted that phosphate minerals would be unusually soluble there. Read more
Scientists develop plastics that degrade in ocean water
Scientists at the University of California (UC) San Diego have developed new biodegradable plastic that can break down in seawater — paving the way for new packaging that can potentially solve the Earth’s plastic waste problem.
Earlier, the team had developed polyurethane foams that can biodegrade in land-based composts.
Upon entering the ocean, plastic waste disrupts marine ecosystems, migrates to central locations and forms trash gyres such as the Great Pacific Garbage Patch, which covers an area more than 1.6 million square kilometres. These plastics never degrade. Instead they break up into smaller particles, eventually becoming microplastics that persist in the environment for centuries.
The team from UC San Diego conducted a series of tests of their biodegradable polyurethane materials.
They found that an assortment of marine organisms colonise the polyurethane foam samples and break the material down to their starting chemicals, which are consumed as nutrients by these microorganisms in the ocean environment.
Data from the study suggest that the microorganisms living in these samples, a mix of bacteria and fungi, live throughout the natural marine environment which suggests that the foams will function similarly across the world. Read more
Polygon-shaped storms on Jupiter baffle scientists
An international team of scientists have created a model that can in part explain why cyclones circling Jupiter’s poles have maintained their polygon shapes for years
In 2017, NASA’s Juno spacecraft found cyclones at Jupiter’s north and south poles. Pictures beamed back by the probe show that these cyclones continue till date, and have not even changed shape.
The images are baffling because on Earth cyclones take shape, travel around for a while and then dissipate.
A group of scientists, led by Andrew P Ingersoll of the California Institute of Technology, have published their findings in the journal Nature Astronomy. It describes how shallow water models were used to at least partly explain how the cyclones last so long.
Photos of the planet’s north pole show that there are eight cyclones surrounding the central cyclone directly over the pole. All eight are in close proximity and all are nearly equidistant from the central cyclone — and are arranged in an octagonal pattern.
A similar arrangement exists at the southern pole where five cyclones are arranged in a pentagon.
The researchers now suggest that there is an “anticyclonic ring” of winds that move in the opposite direction of the cyclones, which is what keeps them in place. Read more
Three new snake species discovered in the Andes
A team of researchers from Khamai Foundation in Ecuador have discovered three new snakes that live underground hidden under graveyards and churches in remote towns in the Ecuadorian Andes.
Following the lead of locals who told them about snakes in the graveyards, they were able to discover a group of burrowing snakes belonging to the genus Atractus. These ground snakes are the most species-rich snake genus in the world.
However, since they tend to remain hidden underground, most people never see them. Most of them inhabit remote cloud forests and live buried underground or in deep crevices. In this particular case, however, two of the new ground snakes were found living among crypts and one was found near a church.
All of this seems to suggest that, at least in the Andes, new species of snakes might be lurking just around the corner. Read more
(Edited by Theres Sudeep)
Source: The Print