Bats use polarized light to navigate: First mammal known...

((The article's title is long so I just shortened it for the title of this thread))

Bats use polarized light to navigate: First mammal known to use polarization patterns in the sky to navigate

Scientists have discovered that greater mouse-eared bats use polarisation patterns in the sky to navigate -- the first mammal that's known to do this.

The bats use the way the Sun's light is scattered in the atmosphere at sunset to calibrate their internal magnetic compass, which helps them to fly in the right direction, a study published in Nature Communications has shown.

Despite this breakthrough, researchers have no idea how they manage to detect polarised light.

"We know that other animals use polarisation patterns in the sky, and we have at least some idea how they do it: bees have specially-adapted photoreceptors in their eyes, and birds, fish, amphibians and reptiles all have cone cell structures in their eyes which may help them to detect polarisation," says Dr Richard Holland of Queen's University Belfast, co-author of the study.

"But we don't know which structure these bats might be using."

Polarisation patterns depend on where the sun is in the sky. They're clearest in a strip across the sky 90° from the position of the sun at sunset or sunrise.

But animals can still see the patterns long after sunset. This means they can orient themselves even when they can't see the sun, including when it's cloudy. Scientists have even shown that dung beetles use the polarisation pattern of moonlight for orientation.

A hugely diverse range of creatures -- including bees, anchovies, birds, reptiles and amphibians -- use the patterns as a compass to work out which way is north, south, east and west.

"Every night through the spring, summer and autumn, bats leave their roosts in caves, trees and buildings to search for insect prey. They might range hundreds of kilometres in a night, but return to their roosts before sunrise to avoid predators. But, until now, how they achieved such feats of navigation wasn't clear," says Stefan Greif of Queen's University Belfast, lead author of the study.

They still don't know fully how the bats are able to use the polarized light to navigate but hopefully with more tests they will be able to figure it out.

Most people over look the importance of bats. They eat insects which in turn saves us from having to use millions of pounds of pesticides. ((Which we know effects RNA of the plants, which in turn effects the RNA of the animals eating those infected plants & finally effects the RNA of us humans who ate the animals. ))

I love bats! We've tried to make them happy here at our place. They eat mosquitoes, and here on the coast they can be pretty bad (the mosquitoes).

Nice find! S & F

a reply to: knoledgeispower
I don't know about the polarized light but one cave I was in maybe 2 miles from the entrance we stopped to take a break, we turned off the lights and we started hearing them flying around they didn't hit us and I don't think they hit the rocks either, we turned the lights on and there was 5 of them flying, we were far enough back that there was no light with all the twist and different levels. Maybe they have more than one way to navigate other than sound. I had thought when they migrate they did it like birds. I do know they have soft fur, I was going through a passage that I had to turn sideways cause my shoulders were too wide to walk through and I brushed on one that was hanging on the wall, I got to reach down and pet his back with my finger then I kept going. They can eat all the bugs they want.

originally posted by: irgust
a reply to: knoledgeispower
I don't know about the polarized light but one cave I was in maybe 2 miles from the entrance we stopped to take a break, we turned off the lights and we started hearing them flying around they didn't hit us and I don't think they hit the rocks either, we turned the lights on and there was 5 of them flying, we were far enough back that there was no light with all the twist and different levels. Maybe they have more than one way to navigate other than sound. I had thought when they migrate they did it like birds. I do know they have soft fur, I was going through a passage that I had to turn sideways cause my shoulders were too wide to walk through and I brushed on one that was hanging on the wall, I got to reach down and pet his back with my finger then I kept going. They can eat all the bugs they want.

From the article

Bats probably use a suite of senses, including the position of the Sun or the stars, Earth's magnetic field, smells, sight, and of course, echolocation to navigate

They don't just rely on polarized light but it's something that they just recently discovered they do. Read the full article, it's not that long and it's pretty cool.

a reply to: knoledgeispower
Actually I did read the article.
But when they say "Scientists have discovered that greater mouse-eared bats use polarization patterns in the sky to navigate" then they say "Despite this breakthrough researchers have no idea how they manage to detect polarized light" it doesn't make it clear, sorry.
I'm not saying they didn't work hard on what they found but if they don't have an idea how they manage to detect the polarized light how do they know the bats use polarization patterns to navigate.
Maybe it's just me, sorry.

originally posted by: irgust
a reply to: knoledgeispower
Actually I did read the article.
But when they say "Scientists have discovered that greater mouse-eared bats use polarization patterns in the sky to navigate" then they say "Despite this breakthrough researchers have no idea how they manage to detect polarized light" it doesn't make it clear, sorry.
I'm not saying they didn't work hard on what they found but if they don't have an idea how they manage to detect the polarized light how do they know the bats use polarization patterns to navigate.
Maybe it's just me, sorry.

They know from the tests they did:

In a bid to shed light on the matter, Holland, Greif and colleagues from Tel Aviv University showed 70 adult, female mouse-eared bats one of two different types of polarisation patterns at sunset.

They then took them to one of two release sites in Bulgaria about 20 to 25 kilometres from their home roost. They released the bats at 01:00 AM -- when no polarisation is visible -- and followed the direction they set off in using small radio transmitters attached to their backs.

They found the bats that had been shown a shifted pattern of polarised light headed off in a direction shifted at right angles from the controls released at the same time.

It's like how we can't see dark matter but we know it is there from the tests that have been done.

a reply to: knoledgeispower
Thanks maybe with more time they will be able to answer more.
I had wondered how they find their way back to the same place every year.
I thought they could see the magnetic energy but I don't know.

originally posted by: irgust
a reply to: knoledgeispower
Thanks maybe with more time they will be able to answer more.
I had wondered how they find their way back to the same place every year.
I thought they could see the magnetic energy but I don't know.

Yea I'm not exactly sure how they do it either but it's very fascinating none the less.

I do hope they will be able to figure it out more too.

We don't often think about how animals are able to get around, especially when they are migrating, so I am glad that there are people out there who do want to know.