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Genomic analysis suggests climate change caused the extinction of wooly rhinos

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Aug. 14 (UPI) — New genomic analysis suggests the decline of the wooly rhinos across ancient Siberia was triggered by climate change, not by overhunting.

Scientists collected and sequenced DNA samples from the frozen remains of 14 well-preserved woolly rhinoceros specimens. Their analysis, detailed this week in the journal Current Biology, showed their population size and genetic diversity was stable in the lead-up to their demise.

Researchers used to think humans showed up in northeastern Siberia just 15,000 years ago, but scientists have since discovered evidence of human habitation dating to 30,000 years ago.

“The decline towards extinction of the woolly rhinoceros doesn’t coincide so much with the first appearance of humans in the region,” senior study author Love Dalén, a professor of evolutionary genetics at the Center for Palaeogenetics, a joint venture between Stockholm University and the Swedish Museum of Natural History, said in a news release. “If anything, we actually see something looking a bit like an increase in population size during this period.”

Dalén and his colleagues collected DNA from tissue, bone and hair samples from wooly rhinos. The data helped researchers measure genetic diversity and gauge the health of ancient populations.

“We examined changes in population size and estimated inbreeding,” said co-first author Nicolas Dussex, a postdoctoral researcher at the Center for Palaeogenetics. “We found that after an increase in population size at the start of a cold period some 29,000 years ago, the woolly rhino population size remained constant and that at this time, inbreeding was low.”

The data showed the size and health of wooly rhino populations remained stable for thousands of years after the arrival of humans. The decline of the region’s megafauna more closely aligns with the rise in temperatures in the region.

The new genomic analysis also showed that like wooly mammoths, wooly rhinos had several genetic mutations that allowed them to adapt to Siberia’s frigid environs.

“We’re coming away from the idea of humans taking over everything as soon as they come into an environment, and instead elucidating the role of climate in megafaunal extinctions,” said co-first author Edana Lord, a doctoral student at the Center for Palaeogenetics. “Although we can’t rule out human involvement, we suggest that the woolly rhinoceros’ extinction was more likely related to climate.”

To get a more precise understanding of the extinction of wooly rhinos and other larger herbivores, researchers hope to collect DNA from rhinos that lived and died closer to when Siberia’s megafauna began their rapid decline, around 14,000 years ago.



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Apple recalls shipment of iPhone 6 Plus due to photo glitch

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CUPERTINO, Calif., Aug. 23 (UPI) — Apple has recalled a shipment of its iPhone 6 Plus due to a technological glitch that produces blurry photos in the device’s camera, the company announced.

The recall affects a small number of iPhone 6 Plus devices, Apple said in a statement, which have demonstrated a glitch in the iSight camera.

Apple said it’s “a component that may fail causing your photos to look blurry.”

Apple created a web page where users can enter their phone’s serial number to determine if they are affected by the recall.

The iPhone 6 and larger iPhone 6 Plus were released last September.



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‘Invisible’ words reveal common structure among famous stories

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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

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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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