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What killed off the dodo? Humans first arrived at Mauritius island in the late 1500s. They found on this island fat flightless birds who nested on the ground and were a convenient way to restock their ship’s food supply. Within 80 years the dodo went extinct. But hunting was not the only, and maybe not even the primary, cause of their extinction. Rather it was likely something that the humans brought with them – invasive species. One species in particular tends to follow humans every where we go, causing havoc on any local ecosystem not already adapted to them – rats.

Dodos nested on the ground and typically had one large egg per nest. This was also a convenient food source for invasive rats, who quickly multiplied and decimated the dodo population. There were other invasive species as well (monkeys and pigs), and there was also habitat loss due to human activity – all of these factors put stress on the dodo population that was unsustainable.

It is an unfortunate unintended consequence of human history that as we explored and populated the world, rats followed us. Rats now exist on every continent except Antarctica, and they are likely the most populous mammal species in the world. They are a clever and adaptive species, and are very good at stowing away. They also reproduce very quickly, with a single female able to produce 50 pups per year. They also have a low mortality rate because they live in communities and protect their young.

But perhaps their most successful feature is that they are well adapted to living off human civilization. They go wherever people go and feed on our refuse. They hide away on ships which means they can get anywhere, including previously isolated island ecosystems. They are good climbers, jumpers, and swimmers and find lots of ways to get on board ships. It is estimated that 40-60% of island bird and reptile extinctions are due to rats.

To be clear, I am not saying rats are somehow inherently bad or to demonize them. They are just really good and what they do, and they have “a particular set of skills” that happened to be optimized for exploiting human civilization. We took a species from Northern China and made it into a globally dominant species (actually there are many species of rat, mostly from Asia originally). The actual culprit here is humans. We are responsible for the rat phenomenon.

There are things we can do about it, however. One thing we can do is eradicate rats from isolated islands so that native species can repopulate. This may require that they be reintroduced (when possible). Obviously we can’t reverse extinction (not yet) but we can reintroduce cousins or species that still exist in other locations or captivity. Once eradicated it is feasible to keep rats from being reintroduced.

Also, seabirds can make a significant come back on these islands once invasive species like rats are removed and native vegetation is restored. There is enough fish to sustain a large seabird population, if they can nest on the island (without rats eating their eggs).

Perhaps the largest island restoration project is Zealandia – which is a project to restore a park in New Zealand to its pre-human habitat. To accomplish this it had to be walled off so that no invasive species could enter. New Zealand is a great example of how the isolation of islands allows them to evolve unique, but vulnerable. ecosystems. New Zealand had almost not mammals and no mammalian predators. This meant the native species had no natural defenses against such predators. The main mammalian predators there now are rats, possum, and stoats, all introduced by humans. They have devastated the local wildlife resulting in an estimated 51 species extinctions.

Islands were most vulnerable to rats and other invasive species, but they also represent a unique opportunity, since it is feasible to eradicate rats there and keep them from being reintroduced. One measure that is important to this effort is good anti-rat standards on all shipping. This means leaving no edible waste around, placing rat barriers on any ropes tying a ship to a dock, setting traps, and being vigilant.

What about on continents and in cities? It is generally believed that once a rat population is established in such a location it is essentially impossible to eliminate it. New York City, for example, has a large and well established rat population. In fact, there is estimated to be over 3 million rats in NYC, with distinct genetic populations in uptown and downtown Manhattan. I visit NYC often, and every time I do you can see rats just walking and and down the sidewalk.

There is something else you see in the city – garbage. Catch and kill mitigation strategies simply will not work in NYC. Rats breed too quickly and there are too many places for them to hide. The number of rats in NYC, some experts argue, is essentially a function of how much food there is in the city for them to eat. The rat problem is a sanitation problem. As with shipping, there needs to be universal and tightly enforced regulations to minimize the availability of garbage for rats to eat. This is happening to some degree, requiring metal garbage containers, for example. But again, anyone who has visited NYC can see quite plainly that garbage remains a serious problem. I get that it is challenging to manage the waste of a city as large and dense and NYC, but it’s not an unsolvable problem. It just requires massive investment and a culture change.

Rats as an invasive species is a problem of our own making (like so many things). But it is also a problem that we have the ability to mitigate.

The post Rats! first appeared on NeuroLogica Blog.

There are so many Russian landmines across Ukraine that removing them could take 700 years. To prioritise areas for de-mining, the Ukrainian government has turned to an artificial intelligence model that can identify the most important regions

How we decide what makes a good topic for a skeptical documentary film.

The Ancient Egyptian Book of the Dead depicts a scene in which a bowel of golden rice is weighed against the feather of truth.

The post Save the Whales, Blind the Children first appeared on Science-Based Medicine.

Eye-contact has a significant impact on interpersonal evaluation, and online job interviews are no exception. In addition to the quality of a resume, the direction of the interviewee's gaze might help (or hinder) their chances of securing the job.

Jupiter’s Great Red Spot (GRS) is one of the Solar System’s defining features. It’s a massive storm that astronomers have observed since the 1600s. However, its date of formation and longevity are up for debate. Have we been seeing the same phenomenon all this time?

The GRS is a gigantic anti-cyclonic (rotating counter-clockwise) storm that’s larger than Earth. Its wind speeds exceed 400 km/h (250 mp/h). It’s an icon that humans have been observing since at least the 1800s, possibly earlier. Its history, along with how it formed, is a mystery.

Its earliest observations may have been in 1632 when a German Abbott used his telescope to look at Jupiter. 32 years later, another observer reported seeing the GRS moving from east to west. Then, in 1665, Giovanni Cassini examined Jupiter with a telescope and noted the presence of a storm at the same latitude as the GRS. Cassini and other astronomers observed it continuously until 1713 and he named it the Permanent Spot.

Unfortunately, astronomers lost track of the spot. Nobody saw the GRS for 118 years until astronomer S. Schwabe observed a clear structure, roughly oval and at the same latitude as the GRS. Some think of that observation as the first observation of the current GRS and that the storm formed again at the same latitude. But the details fade the further back in time we look. There are also questions about the earlier storm and its relation to the current GRS.

New research in Geophysical Research Letters combined historical records with computer simulations of the GRS to try to understand this chimerical meteorological phenomenon. Its title is “The Origin of Jupiter’s Great Red Spot,” and the lead author is Agustín Sánchez-Lavega. Sánchez-Lavega is a Professor of Physics at the University of the Basque Country in Bilbao, Spain. He’s also head of the Planetary Sciences Group and the Department of Applied Physics at the University.

“Jupiter’s Great Red Spot (GRS) is the largest and longest-lived known vortex of all solar system planets, but its lifetime is debated, and its formation mechanism remains hidden,” the authors write in their paper.

The researchers started with historical sources dating back to the mid-1600s, just after the telescope was invented. They analyzed the size, structure, and movement of both the PS and the GRS. But that’s not a simple task. “The appearance of the GRS and its Hollow throughout the history of Jupiter observations has been highly variable due to changes in size, albedo and contrast with surrounding clouds,” they write.

This figure from the research compares the Permanent Spot (PS) and the current GRS. a, b, and c are drawings by Cassini from 1677, 1690, and 1691, respectively. d is a current 2023 image of the GRS. Image Credit: Sánchez-Lavega et al. 2024.

“From the measurements of sizes and movements we deduced that it is highly unlikely that the current GRS was the PS observed by G. D. Cassini. The PS probably disappeared sometime between the mid-18th and 19th centuries, in which case we can say that the longevity of the Red Spot now exceeds 190 years at least,” said lead author Sánchez-Lavega. The GRS was 39,000 km long in 1879 and has shrunk to 14,000 km since then. It’s also become more rounded.

Four views of Jupiter and its GRS. a is a drawing of the Permanent Spot by G. D. Cassini from 19 January 1672. b is a drawing by S. Swabe from 10 May 1851. It shows the GRS area as a clear oval with limits marked by its Hollow (drawn by a red dashed line). c is a Photograph by A. A. Common from 1879. d is a photograph from Observatory Lick with a yellow filter on 14 October 1890. Each image is an astronomical image of Jupiter with south up and east down. Image Credit: Sánchez-Lavega et al. 2024.

The historical record is valuable, but we have different tools at our disposal now. Space telescopes and spacecraft have studied the GRS in ways that would’ve been unimaginable to Cassini and others. NASA’s Voyager 1 captured our first detailed image of the GRS in 1979, when it was just over 9,000,000 km from Jupiter.

Jupiter’s Great Red Spot as imaged by Voyager 1 in 1979. The intricate wave patterns were unseen until this image. Image Credit: By NASA – http://photojournal.jpl.nasa.gov/catalog/PIA00014, Public Domain, https://commons.wikimedia.org/w/index.php?curid=86812

Since Voyager’s image, the Galileo and Juno spacecraft have both imaged the GRS. Juno, in particular, has given us more detailed images and data on Jupiter and the GRS. It captured images of the planet from only 8,000 km above the surface. Juno takes raw images of the planet with its Junocam, and NASA invites anyone to process the images, leading to artful images of the GRS like the one below.

A different take on Jupiter and its GRS. Image Credit: NASA / SwRI / MSSS / Navaneeth Krishnan S © CC BY

Juno also measured the depth of the GRS, something previous efforts couldn’t achieve. Recently, “various instruments on board the Juno mission in orbit around Jupiter have shown that the GRS is shallow and thin when compared to its horizontal dimension, as vertically it is about 500 km long,” explained Sánchez-Lavega.

Jupiter’s atmosphere contains winds running in opposite directions at different latitudes. North of the GRS, winds blow in a westerly direction and reach speeds of 180 km/h. South of the GRS, the winds flow in the opposite direction at speeds of 150 km/h. These winds generate a powerful wind shear that fosters the vortex.

In their supercomputer simulations, the researchers examined different forces that could produce the GRS in these circumstances. They considered the eruption of a gigantic superstorm like the kind that happens, though rarely, on Saturn. They also examined the phenomenon of smaller vortices created by the wind shear that merged together to form the GRS. Both of those produced anti-cyclonic storms, but their shapes and other properties didn’t match the current GRS.

“From these simulations, we conclude that the super-storm and the mergers mechanisms, although they generate a single anticyclone, are unlikely to have formed the GRS,” the researchers write in their paper.

The authors also point out that if either of these had happened, we should’ve seen them. “We also think that if one of these unusual phenomena had occurred, it or its consequences in the atmosphere must have been observed and reported by the astronomers at the time,” said Sánchez-Lavega.

However, other simulations proved more accurate in reproducing the GRS. Jupiter’s winds are known to have instabilities called the South Tropical Disturbance (STrD). When the researchers performed supercomputer simulations of the STrD, they created an anti-cyclonic storm very similar to the GRS. The STrD captured the different winds in the region and trapped them in an elongated shell like the GRS. “We therefore propose that the GRS generated from a long cell resulting from the STrD, that acquired coherence and compactness as it shrank,” the authors write.

These images from the research show how the GRS formed. a is a drawing by T. E. R. Phillips in 1931–1932 of the STrD. The red arrows indicate the flow direction with the longitude scale indicated. b and c are maps drawn from images taken by the New Horizons spacecraft. The yellow arrows mark position-velocity changes in the STrD. The STrD trapped winds and created a long cell that generated the Great Red Spot. Image Credit: Sánchez-Lavega et al. 2024.

The simulations show that over time, the GRS would rotate more rapidly as it shrank and became more coherent and compact until the elongated cell more closely resembled the current GRS. Since that’s what the GRS appears like now, the researchers settled on this explanation.

That process likely began in the mid-1800s when the GRS was much larger than it is now. That leads to the conclusion that the GRS is only about 150 years old.

The post The Great Red Spot Probably Formed in the Early 1800s appeared first on Universe Today.

A novel 256-element wirelessly powered transceiver array for non-line-of-sight 5G communication, featuring efficient wireless power transmission and high-power conversion efficiency, has been designed. The innovative design can enhance the 5G network coverage even to places with link blockage, improving flexibility and coverage area, and potentially making high-speed, low-latency communication more accessible.

A novel 256-element wirelessly powered transceiver array for non-line-of-sight 5G communication, featuring efficient wireless power transmission and high-power conversion efficiency, has been designed. The innovative design can enhance the 5G network coverage even to places with link blockage, improving flexibility and coverage area, and potentially making high-speed, low-latency communication more accessible.

A new way to teach artificial intelligence (AI) to understand human line drawings -- even from non-artists -- has been developed.

A recently developed wirelessly powered 5G relay could accelerate the development of smart factories, report scientists. By adopting a lower operating frequency for wireless power transfer, the proposed relay design solves many of the current limitations, including range and efficiency. In turn, this allows for a more versatile and widespread arrangement of sensors and transceivers in industrial settings.

A recently developed wirelessly powered 5G relay could accelerate the development of smart factories, report scientists. By adopting a lower operating frequency for wireless power transfer, the proposed relay design solves many of the current limitations, including range and efficiency. In turn, this allows for a more versatile and widespread arrangement of sensors and transceivers in industrial settings.

Scientists have proposed a new AI method in which systems of habitual and goal-directed behaviors learn to help each other. Through computer simulations that mimicked the exploration of a maze, the method quickly adapts to changing environments and also reproduced the behavior of humans and animals after they had been accustomed to a certain environment for a long time. The study not only paves the way for the development of systems that adapt quickly and reliably in the burgeoning field of AI, but also provides clues to how we make decisions in the fields of neuroscience and psychology.

Researchers have developed innovative, eco-friendly quantum materials that can drive the transformation of methanol into ethylene glycol. This discovery opens up new possibilities for using eco-friendly materials in photocatalysis, paving the way for sustainable chemical production.

Researchers have developed innovative, eco-friendly quantum materials that can drive the transformation of methanol into ethylene glycol. This discovery opens up new possibilities for using eco-friendly materials in photocatalysis, paving the way for sustainable chemical production.

A new method in spectromicroscopy significantly improves the study of chemical reactions at the nanoscale, both on surfaces and inside layered materials. Scanning X-ray microscopy (SXM) at MAXYMUS beamline of BESSY II enables the investigation of chemical species adsorbed on the top layer (surface) or intercalated within the MXene electrode (bulk) with high chemical sensitivity.

Using computer-assisted neural networks, researchers have been able to accurately identify affective states from the body language of tennis players during games. For the first time, they trained a model based on artificial intelligence (AI) with data from actual games. Their study demonstrates that AI can assess body language and emotions with accuracy similar to that of humans. However, it also points to ethical concerns.

Current techniques for measuring nano/microplastic (N/MP) concentrations in soil require the soil organic matter content to be separated and have limited resolution for analyzing N/MPs sized <1 m. Therefore, researchers have developed a novel yet simple method to measure N/MP concentration in different soil types using spectroscopy at two wavelengths. This method does not require the soil to be separated in order to detect the N/MPs and can accurately quantify N/MPs regardless of their size.

In a breakthrough discovery that challenges the conventional understanding of cosmology, scientists have unearthed new evidence that could reshape our perception of the cosmos. New research shows that rotation curves of galaxies stay flat indefinitely far out, corroborating predictions of modified gravity theory as an alternative to dark matter.

Using a specially designed 3D printed vacuum system, scientists have developed a way to 'trap' dark matter with the aim of detecting domain walls, this will be a significant step forwards in unravelling some of the mysteries of the universe.

A gold-coated milling vessel for ball mills proved to be a real marvel: without any solvents or environmentally harmful chemicals, the team was able to use it to convert alcohols into aldehydes. The catalytic reaction takes place at the gold surface and is mechanically driven. The vessel can be reused multiple times. 'This opens up new prospects for the use of gold in catalysis and shows how traditional materials can contribute to solving modern environmental problems in an innovative way,' says Borchardt.