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Canadian sparrows changing their tune

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The white-throated sparrow of North America, whose singing preferences are the subject of a new study.

WASHINGTON: Members of a Canadian sparrow species famous for their jaunty signature song are changing their tune, a curious example of a “viral phenomenon” in the animal kingdom, a study showed Thursday.

Bird enthusiasts first recorded the white-throated sparrow’s original song, with its distinctive triplet hook, in the 1950s.

Canadians even invented lyrics to accompany the ditty: “Oh my sweet, Ca-na-da, Ca-na-da, Ca-na-da.”

But starting from the late 20th century, biologists began noticing that members of the species in western Canada were innovating.

Instead of a triplet, the new song ended in a doublet and a new syncopation pattern. The new ending sounded like “Ca-na, Ca-na, Ca-na.”

Over the course of the next two decades, this new cadence became a big hit, moving eastward and conquering Alberta, then Ontario. It began entering Quebec last year.

It’s now the dominant version across more than 2,000 miles (3,000 kilometers) of territory, in an extremely rare example of the total replacement of historic bird dialect by another.

Scientist Ken Otter at the University of Northern British Columbia, and his colleague Scott Ramsay from Wilfrid Laurier University, described the dizzying pace of this transformation in the journal Current Biology.

“What we’re seeing is like somebody moving from Quebec to Paris, and all the people around them saying, ‘Wow, that’s a cool accent’ and start adopting a Quebec accent,” Otter told AFP.

Their work was based on 1,785 recordings between 2000 and 2019, the majority made by them but with contributions from citizen-scientists, who posted the files on specialist sites like xeno-canto.org.

In the western province of Alberta, about half of the recorded songs ended with the triplet in 2004; ten years later, all the males had adopted the doublet.

In 2015, half of western Canada had converted to the doublet version, and by last year, the new song had been well established on the western tip of eastern Quebec province.

At this rate, the historic triplet version may soon exist only in tape recordings.

Bird influencers

The males of the species sing to mark their territory, and their songs all share a common structure. Usually, if a variation appears, it remains regional and doesn’t make headway in neighboring territories.

The study represents the first time scientists have been able to show this kind spread at huge geographic scale, said Otter.

So how did it happen?

Probably in the same way that children return from summer camp humming new tunes: songbirds from different parts of Canada winter in the same parts of the United States, then return to their own homes in spring.

The researchers verified this theory by tagging a few of the birds.

So it was that in the plains of Texas and Kansas, the new song’s first adopters from western Canada — avian influencers, if you will — popularized the trend among their eastern brethren.

Previous work has shown that young birds can pick up a foreign song after listening to a recording.

But to truly understand why the males were willing to abandon the old song that had once served them well, the scientists have to rely on theories.

Otter believes it may be because females were more attracted to the new song, so young males rushed to adopt it.

“There seems to be some advantage to adding novel elements into your song that make the song, not necessarily more attractive, but increases people’s attention to it,” said Otter.

Going back to the human example, it would be akin to “if all the French women in Paris thought that a Quebec accent sounded much more interesting than a Parisian accent, and so everybody starts adopting a Quebec accent.”

The hypothesis remains unverified.

Source: – Bangkok Post

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Perseid Meteor Shower Peaks As Waning Moon Meets Venus: What To Watch For In The Night Sky This Week – Forbes

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Each Monday I pick out the northern hemisphere’s celestial highlights (mid-northern latitudes) for the week ahead, but be sure to check my main feed for more in-depth articles on stargazing, astronomy and eclipses. 

What To Watch For In The Night Sky This Week: August 10-16, 2020

Are you ready to go “shooting star”-spotting? Active since July 17, the Perseid meteor shower can bring as many as 100 “shooting stars” per hour on its peak night. In 2020, that’s Tuesday, August 11 into Wednesday, August 12. 

That’s just the beginning of a great week for stargazing. As the week wears on it becomes one of the best weeks of the year to see the Milky Way in the run-up to August 19’s New Moon. From August 12 the Moon will be rising after midnight, giving you a few hours of dark skies just as the brightest part of our galaxy is arcing overhead. 

With two of summer’s celestial treats in the same week, and some great views of Venus and the Moon to boot, a sparkling seven days of stargazing awaits!

Tuesday, August 11, 2020: Perseid meteor shower peaks

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Easily the most popular meteor shower of the year in the northern hemisphere, tonight is one of the best nights of the year to see “shooting stars.” It’s caused by dust and debris left in Earth’s orbital path by Comet 109P/Swift-Tuttle, which last entered the Solar System in 1992 and is due back in July 2126. 

The Perseids can number as many as 100 per hour. Will you see that many? A rising Last Quarter Moon about midnight is going to bleach-out some of the brighter meteors, but there should still be plenty for patient eyes to spot. 

Be outside before midnight. As well as some early “earthgrazers”—long-lasting shooting stars close to the eastern and western horizons—if you’re in a dark place away from light pollution you may also see the Milky Way arcing overhead in the south. 

After midnight, to find shooting stars look at any part of the night sky, and keep looking! However, you’ll need clear skies; if it’s cloudy, you’re not going to see anything.

It’s also worth looking for Perseid meteors on Wednesday, August 12 into Thursday, August 13, and even the night after that. If there’s a clear sky this week, get outside and look up.

Wednesday, August 12 – Saturday, August 22: See the Milky Way

Did you manage to sneak a peak at our galaxy while out watching for Perseids?

The center of our galaxy looks spectacular in August, but the Milky Way is at its best when the Moon is down. That’s from tonight through August 19’s New Moon.

Look generally south, preferably while observing from somewhere away from light pollution and, crucially, somewhere where your view to the southern horizon isn’t going to have the glow from any town or city. 

Thursday, August 13, 2020: Venus as a ‘Morning Star’ and Aldebaran close to the Moon

If you enjoyed seeing Venus dominate as an “Evening Star” for the first half of 2020, now is the best time to appreciate how much it’s now dominating as a pre-dawn “Morning Star.”

Always the brightest object in the night sky aside from the Moon, Venus today reaches its greatest elongation west. 

That means it seems, from our point of view one Earth, to be furthest from the Sun in its current morning apparition, so it appears at its highest point in the pre-dawn night sky. Look above the eastern horizon about three hours before sunrise.

At 45.8° west of the Sun, it’s the highest in the night sky Venus will get during 2020. 

If you’re up early enough to see Venus, do have a look for bright star Aldebaran in the constellation of Taurus, which will be a mere 4° from a 34% illuminated Moon. 

Saturday, August 15, 2020: conjunction of a crescent Moon and Venus

This morning Venus will still be rising about three hours before the Sun, together with an 18%-lit crescent Moon (see above) that will seem closer to it the nearer it gets to sunrise.

Constellation of the week: Orion

Look to the east and, if you’re up earlier enough, you can also indulge in some good views of the winter constellations. 

Most notably you’ll see the famous cold weather constellation of Orion rising on its side. Its bright stars, ruddy Betelgeuse and true blue Rigel, should both be just about visible. Between them will the Belt; above will be the constellation of Taurus and bright red star Aldebaran.

Further proof that although the stars change with the seasons, if you get up early enough you can cheat the system! 

Wishing you clear skies and wide eyes. 

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NASA’s InSight lander shows what’s beneath Mars’ surface – Digital Trends

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Scientists are learning more about the interior structure of Mars and have found the depths of three boundaries beneath the planet’s surface. “Ultimately it may help us understand planetary formation,” Alan Levander, co-author of the study said in a statement.

This is the first time that these boundaries have been measured directly. Investigating the planet’s interior is complicated because it doesn’t have tectonic plates like Earth does.

“In the absence of plate tectonics on Mars, its early history is mostly preserved compared with Earth,” co-author Sizhuang Deng said in the statement. “The depth estimates of Martian seismic boundaries can provide indications to better understand its past as well as the formation and evolution of terrestrial planets in general.”

NASA

The data was collected using NASA’s InSight lander, which uses an instrument called a seismometer to measure vibrations coming from within Mars. It detects marsquakes, in which seismic waves pass through the planet, which can be used to infer details about the density and the composition of the planet beneath the surface.

“The traditional way to investigate structures beneath Earth is to analyze earthquake signals using dense networks of seismic stations,” Deng said in the statement. “Mars is much less tectonically active, which means it will have far fewer marsquake events compared with Earth. Moreover, with only one seismic station on Mars, we cannot employ methods that rely on seismic networks.”

An artist’s impression of Mars’ inner structure. The topmost layer is the crust, and beneath it is the mantle, which rests on a solid inner core.
An artist’s impression of Mars’ inner structure. The topmost layer is the crust, and beneath it is the mantle, which rests on a solid inner core. NASA/JPL-Caltech

The team found three boundaries within the inner structure of Mars: A divide between the crust and the mantle, located 22 miles beneath the surface, a transition within the mantle from an area where magnesium iron silicates form a mineral called olivine to one where they form wadsleyite, which is found between 690 miles and 727 miles beneath the surface, and the divide between the mantel and the core, which is located between 945 miles and 994 miles beneath the surface.

This information reveals more not only about how the planet exists now, but could also be used to investigate how Mars developed over time.

The findings are published in the journal Geophysical Research Letters.

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THIS WEEK @NASA: First Commercial Crew Flight to Space Station Safely Splashes Down – SpaceCoastDaily.com

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Latest Happenings around NASA

[embedded content]

ABOVE VIDEO: A safe splashdown for an historic test flight, a major milestone for a future mission, and remembering a champion for Earth Science … a few of the stories to tell you about – This Week at NASA!

First Commercial Crew Flight to Space Station Safely Splashes Down

SpaceX Mission Control:
(Sound of capsule hitting water) “Splashdown! As you can see on your screen, we have visual confirmation for splashdown!”

On Aug. 2, the SpaceX Endeavour Crew Dragon spacecraft splashed down in the Gulf of Mexico, safely returning our Doug Hurley and Bob Behnken from an historic test mission to the International Space Station, and marking a new era in human spaceflight.

Jim Bridenstine/NASA Administrator:
“This is really an amazing day, but we also need to remember that this is just the beginning. The future is very bright, but it’s going to require these public/private partnerships which we have now proven can be very, very successful.”

Gwynne Shotwell/SpaceX President and Chief Operating Officer:
“We are starting the journey of bringing people regularly to and from low-Earth orbit and on to the Moon and then ultimately on to Mars.”

Behnken and Hurley’s 62-day stay onboard the space station was very busy. They spent more than 100 hours working with science investigations, and participated in four spacewalks, which saw Behnken and fellow NASA astronaut Chris Cassidy tie the record for most spacewalks by a U.S. astronaut.

Douglas Hurley/NASA Astronaut:
“To see those two work out on the International Space Station, you’re not going to see anything like that again. It was just amazing to be part of that.”

The splashdown of NASA’s SpaceX Demo-2 mission was the first with American astronauts since the Apollo-Soyuz Test Project 45 years ago. Review of the mission and spacecraft could pave the way for NASA to certify SpaceX’s systems for regular crewed flights to the space station, including Crew-1, the first rotational mission later this year.

Robert Behnken/NASA Astronaut:
“I think this kind of comes full circle. It took years to get here; we brought the capability back to America, and we came home safely to our families. And it took a lot of people a lot of time to make that happen.”

NASA’s Lucy Mission Passes Critical Mission Milestone

Our Lucy mission has been cleared to proceed with assembly and testing in preparation for its targeted launch in 2021. Lucy will be the first mission to study Jupiter’s Trojan asteroids. For more, go to: nasa.gov/lucy.

NASA Remembers Distinguished Earth Scientist Mike Freilich

NASA joins the entire science community in mourning the loss of Mike Freilich, former director of the agency’s Earth Science Division. In a statement, NASA Administrator Jim Bridenstine noted that Freilich’s deep expertise and innate love of science helped us expand the ways we observe our home planet. Earlier this year NASA joined several agencies and international partners to rename a mission after him. The Sentinel-6 Michael Freilich mission will gather critical information about the oceans for which he had such an abiding passion.

NASA Provides Data on Isaias

This image was taken by our Terra satellite on Aug. 3, about 9 hours and 40 minutes before the eye of Hurricane Isaias made landfall in southern North Carolina, packing maximum sustained winds of 85 mph. NASA satellites provided forecasters with rainfall rates, cloud top temperatures, and other data as the huge storm made its way up the U.S. East Coast.

NASA Monitors California’s Apple Fire From Space

An instrument aboard the International Space Station that measures the temperature of plants as they run out of water, produced this temperature map showing the Apple wildfire burning just east of Los Angeles. The fire had consumed about 4,000 acres at the time the image was captured. In just two days, that number grew to more than 26,000 acres.

That’s what’s up this week @NASA

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