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Territorial aggression between bird species more common than thought



May 26 (UPI) — Territorial aggression between different species was thought to be rare, but new research suggests the behavior is surprisingly common among perching birds, a group that includes songbirds and their closest relatives.

The new study, published Tuesday in the journal PNAS, suggests territorial aggression between species is driven by competition for breeding grounds and hybridization.

Hybrid species and species known to mate with other species are more likely to share common breeding grounds. The latest research showed the competition for these grounds inspires territorial aggression toward other species.

“We designed our analyses to be able to test this hypothesis — that is, the hypothesis that competition for access to mates might drive the evolution of territoriality between species,” lead study author Jonathan Drury, an assistant professor of ecology, evolution and the environment at Durham University in Britain, told UPI in an email.

“Combined with our results about resource competition, it appears that territorial aggression between species evolves for the same reasons that territoriality between members of the same species evolves,” Drury said.

Using the observational data from previous surveys, Drury and his colleagues conducted a large-scale phylogenetic analysis of the distribution of territorial aggression among passerine birds.

“We find that interspecific territoriality is widespread in birds and strongly associated with hybridization and resource overlap during the breeding season,” researchers wrote in their paper.

Scientists chose to focus on passerine birds, or perching birds, because they are the focus of most ornithological studies, and as a result, there is a lot of related observational data to be mined for fresh insights.

In analyzing the scientific literature on the breeding patterns of passerine species, Drury and his colleagues found roughly 28 percent of perching bird species form hybrids with one or more other species. That’s a lot of birds with overlapping breeding territories, he said, which explains the prevalence of territorial aggression.

“Territorial behavior can include things like physical attacks, chases, displays, and territorial counter singing,” Drury said. “In our study, we limited our set of observations to clear-cut accounts of competition for space, rather than for food — so, behaviors like aggression at bird feeders weren’t included.”

Hybridizing species might get along better if there was more space to spread out, according to Drury.

“Human activities are causing many changes to the geographical distributions of species, and when individuals of a species reach a novel location, they are likely to interact behaviorally with individuals of other species,” he said. “This research shows that behavioral interactions between newly arriving species and species that were already there are important to account for in conservation efforts.”

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‘Invisible’ words reveal common structure among famous stories



Aug. 7 (UPI) — Storytelling requires a narrative arc, but the trajectory of a dramatic arc isn’t always obvious.

By tracing the abundance of “invisible” words — pronouns, articles and other short words — researchers were able to identify patterns shared by a diversity of stories, from Shakespeare to Spielberg, according to a study published Friday in Science Advances.

“Over the years, these ‘invisible’ words have been found to be related to a whole mess of psychological processes — how people use small words like articles and pronouns tell us about a person’s mental health, thinking style, their social status, and even how well they get along with other people,” study lead author Ryan Boyd told UPI.

“In many ways, it was a natural progression to look at what these words can tell us how the nature of stories,” said Boyd, a lecturer in behavioral analytics at the University of Leeds.

For the study, Boyd and his colleagues used a range of statistical techniques to analyze the abundance and distribution of invisible words in 40,000 fictional texts, including short stories, novels and movie scripts.

The analysis revealed a common structure — a so-called narrative curve — featuring three distinct phases.

During the “staging” phase, authors use prepositions and articles in greater abundance, peppering their prose with “a” and “the.” These words are more useful at the beginning, when authors must set the scene and provide the audience with basic information.

The middle phase is defined by plot progression, which is revealed by a greater abundance of auxiliary verbs, adverbs and pronouns — or interactional language. During this phase, “the house” from the staging phase becomes “her home” or “it.”

During the third phase, cognitive tension is ramped up as the narrative arc reaches a climax. As the author guides the reader or viewer through the process of conflict resolution, cognitive-processing words like “think,” “believe,” “understand” and “cause” begin to crop up in greater numbers.

Researchers found this three-phase narrative shape remained consistent, regardless of a stories length.

“A 25,000 word story has the same shape as a 250 word story,” said Boyd, lead author of the new study. “It seems, then, that we are able to do a good job of structuring our stories in an optimal way regardless of how much space we have to do it in.”

The researchers set up a website showing the shapes of staging, plot progression and cognitive tension in eight texts at The Arc of Narrative website.

The patterns left by invisible words proved both good and bad stories — tales spun by amateurs, as well as professionals — utilize similar structures.

“Our results confirm what people have long believed about stories,” Boyd said. “Like DNA, we knew about it long before we could actually see it and measure it. With these new methods, we are able to see and measure the ‘DNA’ of stories and understand them in more objective, scientific ways.”

According to Boyd, studying the patterns of stories can offer insights into cognitive processes unique to humans.

“What these story shapes seem to tell us is that we have, to some degree, evolved to process information in certain ways,” he said. “We need to understand the ‘who’ and ‘what’ in order to understand the ‘why’ of our everyday lives and the lives of others.”

The authors of the latest story are already mining text for other language patterns that might help researchers determine whether a story-teller is telling the truth, or perhaps reveal the secrets to a “good” story.

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Florida Current study confirms decline in strength of Gulf Stream



Aug. 7 (UPI) — New research suggests the strength of the Florida Current, which forms the beginning of the Gulf Stream, has weakened considerably over the last century.

The findings, published Friday in the journal Nature Climate Change, corroborate the predictions of several models that suggest the Gulf Stream has slowed over the last several decades.

The Florida Current is a thermal ocean current that flows from west to east around the tip of Florida, joining the Gulf Stream off Florida’s east coast.

Scientists have been tracking the strength of the Florida Current since the early 1980s — not long enough to identify multi-decadal or centennial trends.

To better understand the current’s historical changes, Christopher Piecuch, researcher at the Woods Hole Oceanographic Institution in Massachusetts, decided to study the relationship between coastal sea level and the strength of near-shore currents.

While researchers have only been measuring the Florida Current for a few decades, scientists have been recording sea level data since the early 1900s. Piecuch was able to use the data to predict historic changes in the strength of near-shore currents.

“In the ocean, almost everything is connected,” Christopher Piecuch, sole author of the new study, said in a news release. “We can use those connections to look at things in the past or far from shore, giving us a more complete view of the ocean and how it changes across space and time.”

The statistical analysis performed by Piecuch showed the Florida Current and Gulf Stream are the weakest they’ve been during the last 110 years.

The findings are in agreement with ocean current models that suggest climate change has caused a slowdown of the Atlantic Meridional Overturning Circulation, of which the Gulf Stream is a part.

Piecuch said he hopes his research will help other scientists use coastal current data to study changes in bigger currents like the Gulf Stream.

“If we can monitor something over the horizon by making measurements from shore, then that’s a win for science and potentially for society,” he said.

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SpaceX, ULA win large government launch contracts



Astronauts make round trip to space station from U.S. soil

NASA astronaut Douglas Hurley (C) waves to onlookers as he boards a plane at Naval Air Station Pensacola to return him and NASA astronaut Robert Behnken home to Houston a few hours after the duo landed in their SpaceX Crew Dragon Endeavour spacecraft off the coast of Pensacola, Fla,, on August 2, 2020. Photo by Bill Ingalls/NASA | License Photo

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