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Climate Crisis: Hurricanes Are Making Some Spiders More Aggressive – Inverse

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In the most uncomfortable piece of climate crisis-related news yet, a team of scientists believe that the increasing tropical cyclones may be changing the temperament of a “super abundant” spider. As the storms continue to increase in tandem with the planet’s temperature, some of our eight-legged friends are starting to get more aggressive, report scientists in a paper published Monday in Nature Ecology and Evolution.

Specifically, these findings refer to a species of group-dwelling spiders called Anelosimus studiosus. They’re “hardly majestic,” lead study author Jonathan Pruitt, Ph.D., an associate professor at the University of California Santa Barbara, tells Inverse, but they happen to have very intricate social lives. Along the Gulf Coast, the spiders form multi-female groups that hunt in packs, dwell in group webs, and sometimes rear each other’s children. But the climate crisis may be shifting these old spider traditions toward a less interconnected lifestyle.

In the paper, Pruitt and his team show that hurricanes are actually changing the social and behavior dynamics of these spider colonies. The aggressive spiders in the colonies are well-equipped to handle the chaos, but the less aggressive ones are not. That inequality, he explains, may reshape life in the colony.

“There’s a behavioral tipping point when very very aggressive colonies stop working together, start killing each other, and the group wisely disbands,” he says. “Combine hurricane increases with global warming and I think you could get something like that.”

Anelosimus studiosus, a social cobweb spider, can live in groups, but if the group becomes too aggressive it can disband. 

The species as a whole will fare just fine, he says, in case you’re worried about losing even more animal and insect species to climate change. But the spiders are a good example of the way incomprehensibly large events — say, increases in large storms — can cause minute but significant changes too, like the behavior of a five-millimeter-long spider.

How Storms Change Spider Behavior

Anelosimus studiosus have two “behavioral” phenotypes (traits) that seem to be heritable, suggesting that they each have a genetic underpinning.

Some individuals are naturally more aggressive, which means that they swiftly attack in large numbers, kill their mates, are more wasteful their their prey, and are prone to fight among themselves; they also happen to be better at foraging when resources are scarce. The other individuals tend to be more docile, so they’re better at coexisting. To survive in a colony, you need a balance of both.

But Pruitt’s work suggests that tropical cyclones are selecting for the aggressive spiders. He observed 240 colonies before and after Hurricane Florence, Hurricane Michael, and tropical storm Alberto in the fall of 2018, finding that, while roughly 75 percent of each colony survived the storm, the colonies with more aggressive foraging responses produced more egg cases than the colonies with less aggressive tendencies.

Over time, this process shifts the nature of the colony toward the more aggressive types.

What Aggressive Behavior Means For the Species

While this shift likely won’t impact the species’ chances of survival, it does edge in on a “behavioral” tipping point. A colony of overly aggressive spiders, honed by the hostile summer cyclones of the Southern USA, is unlikely to cohabitate, says Pruitt. So if this trend continues, these spiders, which traditionally live in tight communities, may each decide to go it alone.

“I think the species as a whole will fare fine. But, if tropical cyclones start striking some regions all of the time (e.g., annually), then we might see this species revert back to is ancestral solitary state, where females no longer work together and they go it alone,” he explains.

Already, we know that extreme environmental disturbances (like the once predicted with increasing global temperature), will profoundly affect which species will live and die. But Pruitt’s work also shows a more nuanced approach to how climate change will impact species, as Eric Ameca, an ecologist who studies biodiversity and response to extreme climate events, adds in a commentary accompanying the new paper. While some species do have adaptive responses (so they’ll probably make it out okay), Ameca writes, they may look or behave a lot differently due to these extreme weather events.

Pruitt for one, sees the changing behavior of his spiders as a puzzle to be solved — and maybe applied across species in the future.

“It also means that the future of life, how it operates, and who prevails in the face of changing environments is going to be a very difficult puzzle to solve. Thankfully, humans like puzzles,” he says.

Abstract:

Extreme events, such as tropical cyclones, are destructive and influential forces. However, observing and recording the ecological effects of these statistically improbable, yet pro- found ‘black swan’ weather events is logistically difficult. By anticipating the trajectory of tropical cyclones, and sampling populations before and after they make landfall, we show that these extreme events select for more aggressive colony phe- notypes in the group-living spider Anelosimus studiosus. This selection is great enough to drive regional variation in colony phenotypes, despite the fact that tropical cyclone strikes are irregular, occurring only every few years, even in particularly prone regions. These data provide compelling evidence for tropical cyclone-induced selection driving the evolution of an important functional trait and show that black swan events contribute to within-species diversity and local adaptation.

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Elon Musk’s Starlink Satellites Are Already Causing a Headache for Astronomers – Gizmodo

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Several Starlink satellites in orbit, as seen above the Cerro Tololo Observatory in Chile on November 18.
Image: Clara Martínez-Vázquez, Cliff Johnson, CTIO/AURA/NSF

Astronomers at a Chilean observatory were rudely interrupted earlier this week when a SpaceX satellite train consisting of 60 Starlink satellites drifted overhead, in what scientists are apparently going to have to accept as the new normal.

Launched into orbit on November 11, the Starlink smallsat train took five minutes to pass over the Cerro Tololo Inter-American Observatory in Chile, according to a tweet from astronomer Clarae Martínez-Vázquez.

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“Wow!! I am in shock!!,” tweeted Martínez-Vázquez. “The huge amount of Starlink satellites crossed our skies tonight at [Cerro Tololo]. Our DECam [Dark Energy Camera] exposure was heavily affected by 19 of them!,” to which she added: “Rather depressing… This is not cool!”

Responding to this tweet, astronomer Cliff Johnson, a team member and a CIERA Postdoc Fellow in Astronomy at Northwestern, tweeted out a view of the disrupted data, showing an array of satellite trails strewn across an image of space.

The astronomers were collecting data using the DECam instrument, a high-performance, wide-field imager on the CTIO Blanco 4-meter telescope, as part of the DELVE survey, which is currently mapping the outer fringes of the Large and Small Magellanic Clouds as well as a significant fraction of the southern sky at optical wavelengths. Key goals of the project are to study the stellar halo around the Magellanic Clouds and detect new dwarf galaxies in orbit around the Clouds or the nearby Milky Way.

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The Starlink-tarnished DECam frame, showing satellite trails across the field of view.
Image: Clara Martínez-Vázquez, Cliff Johnson, CTIO/AURA/NSF

But this research was punctuated as the Starlink train passed overhead during the early morning of Monday, November 18.

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“In this case, 1 out of about 40 exposures we took during our half-night of observations was affected by the satellite trails,” Johnson told Gizmodo in an email. “And in the case of that single exposure, a maximum of 15 percent of the image was affected by the trails. Beyond the image itself, we also had to be careful as the trail-affected image also impacted our survey operations due to the large number of image artifacts biasing our quality-control measurements.”

Taken as a whole, however, “these numbers tend to show that the effect on our science was more on the annoyance level rather than total disruption,” he wrote. That said, “this may only be the beginning of problems for astronomers, so I believe the community reaction and alarm is warranted.” Should the proposed sizes of these satellite megaconstellations—which are projected to include upwards of tens of thousands of individual elements—actually be achieved, “that has the potential to significantly impact our observational data,” said Johnson.

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A similar thing happened earlier this year after the first batch of 60 Starlink satellites was delivered to orbit, with some people even believing they were UFOs. Alarmed by the inaugural batch of Starlink satellites, the U.S. American Astronomical Society issued a warning, saying megaconstellations could threaten scientific observations of space.

The train effect, in which the satellites are lined up neatly in a bright row, is a temporary one. Eventually, the smallsats disperse and enter into their own unique orbits in a process that takes a few weeks. That said, the number of objects in space—dispersed or not—is about to experience a dramatic uptick.

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As it stands, the impacts of these satellite trains “remain manageable” and the “worst effects temporary,” Johnson told Gizmodo.

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“I agree with the tone of the recent IAU statement that calls for immediate, meaningful discussion between regulators, satellite providers, and astronomers to highlight ways that impacts to astronomy can be minimized—and not just optical, but radio astronomy as well—and rule out the worst-case scenarios of unlimited launches and unchecked deployments,” Johnson told Gizmodo.

In response to these concerns, SpaceX has said it is taking steps to color the base of Starlink satellites black, in order to minimize their brightness. Experts aren’t convinced that’ll work, as some observatories use super-sensitive instruments to detect even the faintest objects.

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Scientists will likely have to get used to these sorts of disruptions, as regulating bodies aren’t lending a sympathetic ear. SpaceX has already received approval from the U.S. Federal Communications Commission (FCC) to launch 12,000 Starlink smallsats, and in October, the Elon Musk-led private space firm asked the FCC for permission to launch an additional 30,000 satellites on top of that by the mid 2020s. These satellite trains, along with their associated megaconstellations, will soon become a regular fixture of the night sky—and that doesn’t include constellations that are set to be built by SpaceX’s competitors, including networks proposed by OneWeb, Telsat, and Amazon.

With the starry night already obscured by light pollution from our cities, it seems an unhindered view into space may soon elude astronomers as well.

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Photos Show Evidence of Life on Mars, Claims Scientist – NDTV

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As scientists scramble to determine whether there is life on Mars, a researcher from Ohio University in US believes that there is evidence of insect-like creatures on the red planet.

Courtesy photographs from various Mars rovers, Professor Emeritus William Romoser’s research found numerous examples of insect-like forms, structured similarly to bees, as well as reptile-like forms, both as fossils and living creatures.

“There has been and still is life on Mars,” Romoser said, noting that the images appear to show both fossilised and living creatures.

“There is apparent diversity among the Martian insect-like fauna which display many features similar to Terran insects that are interpreted as advanced groups – for example, the presence of wings, wing flexion, agile gliding/flight, and variously structured leg elements,” Romoser added.

Romoser said that while the Martian rovers, particularly the Curiosity Rover, have been looking for indicators of organic activity, there are a number of photos which clearly depict the insect- and reptile-like forms.

Photo Credit: Ohio University

Numerous photos show images where arthropod body segments, along with legs, antennae and wings, can be picked out from the surrounding area, and one even appears to show one of the insects in a steep dive before pulling up just before hitting the ground.

Individual images were carefully studied while varying photographic parameters such as brightness, contrast, saturation, inversion, and so on. No content was added, or removed.

Criteria used in Romoser’s research included: Dramatic departure from the surroundings, clarity of form, body symmetry, segmentation of body parts, repeating form, skeletal remains, and observation of forms in close proximity to one another.

Particular postures, evidence of motion, flight, apparent interaction as suggested by relative positions, and shiny eyes were taken to be consistent with the presence of living forms.

“Once a clear image of a given form was identified and described, it was useful in facilitating recognition of other less clear, but none-the-less valid, images of the same basic form,” Romoser said. “

An exoskeleton and jointed appendages are sufficient to establish identification as an arthropod.

Three body regions, a single pair of antennae, and six legs are traditionally sufficient to establish identification as ‘insect’ on Earth.

These characteristics should likewise be valid to identify an organism on Mars as insect-like. On these bases, arthropodan, insect-like forms can be seen in the Mars rover photos.”

These creatures loosely resemble bumble bees or carpenter bees on Earth. Other images show these “bees” appearing to shelter or nest in caves. And others show a fossilized creature that resembles a snake.

“The presence of higher metazoan organisms on Mars implies the presence of nutrient/energy sources and processes, food chains and webs, and water as elements functioning in a viable, if extreme, ecological setting sufficient to sustain life,” Romoser said.

“The evidence of life on Mars presented here provides a strong basis for many additional important biological as well as social and political questions,” he added.

The study was presented at Entomological Society of America national meeting.

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Starlink Satellites Posing Issues For Astronomers – Hackaday

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Spotting satellites from the ground is a popular pastime among amateur astronomers. Typically, the ISS and Iridium satellites have been common sightings, with their orbits and design causing them to appear sufficiently bright in the sky. More recently, SpaceX’s mass launches of Starlink satellites have been drawing attention for the wrong reasons.

A capture from the Cerro Telolo observatory, showing the many Starlink satellite tracks spoiling the exposure.

Starlink is a project run by SpaceX to provide internet via satellite, using a variety of techniques to keep latency down and bandwidth high. There’s talk of inter-satellite laser communications, autonomous obstacle avoidance, and special designs to limit the amount of space junk created. We’ve covered the technology in a comprehensive post earlier this year.

The Starlink craft have long worried astronomers, who rely on a dark and unobstructed view of the sky to carry out their work. There are now large numbers of the satellites in relatively low orbits, and the craft have a high albedo, meaning they reflect a significant amount of the sunlight that hits them. With the craft also launching in a closely-packed train formation, there have already been impacts on research operations.

There is some hope that as the craft move to higher orbits when they enter service, this problem will be reduced. SpaceX are also reportedly considering modifications to the design to reduce albedo, helping to keep the astronomy community onside. Regardless, with plans on the table to launch anywhere from 12,000 to 42,000 satellites, it’s likely this isn’t the last we’ll hear about the issue.

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