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Local adaptation may buffer some birds against climate change

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<div data-thumb=”https://scx1.b-cdn.net/csz/news/tmb/2023/local-adaptation-may-b-1.jpg” data-src=”https://scx2.b-cdn.net/gfx/news/hires/2023/local-adaptation-may-b-1.jpg” data-sub-html=”Song sparrow subspecies distribution, genetic divergence, and body size variation. Credit: Nature Communications (2023). DOI: 10.1038/s41467-023-42786-2″>

Song sparrow subspecies distribution, genetic divergence, and body size variation. Credit: Nature Communications (2023). DOI: 10.1038/s41467-023-42786-2

North American song sparrows may be more resilient to climate change thanks to a remarkable adaptation: a stunning range of body sizes found throughout the bird’s westernmost range.

Cornell researchers and their colleagues have done whole genome sequencing of North American that has revealed the for the range of body sizes. This work is the first result from a larger research effort to sequence genomes from across North America, spanning nearly all of the 25 recognized subspecies.

The current research published in Nature Communications by scientists from the University of British Columbia, the Cornell Lab of Ornithology, Ouachita Baptist University and the University of Alaska, Fairbanks.

The study offers support for what is known as Bergmann’s Rule, which states that broadly speaking, among organisms that regulate their own heat, in leads to larger-bodied organisms while lead to smaller bodies. Larger bodies are more efficient at retaining heat. Smaller bodies allow an organism to stay cooler.

Song sparrows that live year-round on Alaska’s Aleutian Islands can be up to three times larger than their cousins near San Francisco Bay.

“The size difference among song sparrows is wild to even think about,” said co-author and researcher Jennifer Walsh at the Cornell Lab of Ornithology. “Our results show that song sparrows have substantial capacity for adapting to local environmental change, and the genetic mechanisms underlying those changes are quite clear. We thought there would be a more complicated genetic component, or many more genes working together, to create the huge size difference.”

For this study, the researchers sequenced and compared 79 genomes from nine song sparrow subspecies originating from multiple locations, work done at the Fuller Evolutionary Biology Program at the Cornell Lab of Ornithology.

<div data-thumb=”https://scx1.b-cdn.net/csz/news/tmb/2023/local-adaptation-may-b.jpg” data-src=”https://scx2.b-cdn.net/gfx/news/hires/2023/local-adaptation-may-b.jpg” data-sub-html=”Genome-wide differentiation between northern subspecies. Genome-wide distribution of FST for pairwise comparisons between large- and smaller-bodied northern subspecies (white background) and control comparisons (gray background). Manhattan plot show genome-wide differentiation in 50-kb windows. The dashed line indicates the 99.9th percentile of genome-wide mean. The yellow highlighted regions indicate a subset of divergent windows on contigs 3361 (chr 2), 1534 (chr 3), and 391 (chr 17) held in common between all pairs. Chromosomes were identified by their position on the zebra finch genome. Credit: Nature Communications (2023). DOI: 10.1038/s41467-023-42786-2″>

Local adaptation may buffer some birds against climate change
Genome-wide differentiation between northern subspecies. Genome-wide distribution of FST for pairwise comparisons between large- and smaller-bodied northern subspecies (white background) and control comparisons (gray background). Manhattan plot show genome-wide differentiation in 50-kb windows. The dashed line indicates the 99.9th percentile of genome-wide mean. The yellow highlighted regions indicate a subset of divergent windows on contigs 3361 (chr 2), 1534 (chr 3), and 391 (chr 17) held in common between all pairs. Chromosomes were identified by their position on the zebra finch genome. Credit: Nature Communications (2023). DOI: 10.1038/s41467-023-42786-2

Tissue samples used for this study came from specimens at the University of Alaska Museum of the North, collected between 1997 and 2000, along with previously published whole genomes for California subspecies. Song sparrows are an especially useful study species because they are so widespread and are adapted to live in so many different types of environments.

“We found eight gene variations in the genomes we sequenced, all associated with body mass as predicted by Bergmann’s Rule,” said lead author Katherine Carbeck, a Ph.D. candidate at the University of British Columbia in Vancouver. “What this tells us is that there is a for song sparrow adaptation to local climate conditions, stretching from the coldest locations in the far north to the warmest parts of its range in California.”

We tend to think of evolution as occurring over millions of years, but microevolutionary processes—changes taking place over a short period of time—play a crucial role in helping song sparrows survive even in novel climate conditions, Carbeck said.

The findings suggest a resilient future for these birds, said Peter Arcese, a co-author and professor in UBC’s department of forest and conservation sciences.

“Our findings imply that some, if not all, locally adapted song sparrow populations may continue to adapt to climate change, as long as we maintain habitat conditions that facilitate the movement of individuals and genes between populations,” he said.

Understanding the nuances of microevolution makes a difference when it comes to conservation, the scientists said. For example, song sparrows in northwestern regions, such as Alaska and British Columbia, show stable or increasing populations currently, but the opposite is true for populations along the West Coast of the continental United States, with some San Francisco Bay populations listed at the state level as threatened.

Declines in one portion of the range could mean loss of genetic diversity in locally specialized populations, despite the overall trends for the species. And though song sparrows have been shown to be very adaptable to local climates, there is a limit.

“Although micro-evolution has the potential to partly offset the effects of climate change,” Carbeck said, “the key question is whether local adaptation can keep pace with the speed at which overall is happening.”

More information:
Katherine Carbeck et al, Candidate genes under selection in song sparrows co-vary with climate and body mass in support of Bergmann’s Rule, Nature Communications (2023). DOI: 10.1038/s41467-023-42786-2

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Here’s how Helene and other storms dumped a whopping 40 trillion gallons of rain on the South

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More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.

That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.

“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”

The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.

Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.

Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.

Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.

Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.

Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.

“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”

The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.

North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.

Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”

Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.

Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.

For Dello, the “fingerprints of climate change” were clear.

“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”

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Follow AP’s climate coverage at https://apnews.com/hub/climate

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Follow Seth Borenstein on Twitter at @borenbears

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Associated Press climate and environmental coverage receives support from several private foundations. See more about AP’s climate initiative here. The AP is solely responsible for all content.

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‘Big Sam’: Paleontologists unearth giant skull of Pachyrhinosaurus in Alberta

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It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.

On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.

They call it “Big Sam.”

The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.

It didn’t die alone.

“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.

She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”

“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.

The head alone, she said, is about the size of a baby elephant.

The discovery was a long time coming.

The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.

“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.

When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”

“It contains about 100 to 300 bones per square metre,” she said.

Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.

About a year ago, they found the second adult: Big Sam.

Bamforth said both dinosaurs are believed to have been the elders in the herd.

“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.

“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”

The genders of the two adults are unknown.

Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.

The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.

She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.

“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.

“It’s pretty exciting.”

This report by The Canadian Press was first published Sept. 25, 2024.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

The Canadian Press. All rights reserved.

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