This moth uses the stars to navigate on its epic 1,000 km migration
An Australian moth follows the stars during its yearly migration, using the night sky as a guiding compass, according to a new study.
When temperatures heat up, nocturnal Bogong moths fly about 1,000 kilometres to cool down in caves by the Australian Alps. They later return home to breed and die.
Birds routinely navigate by starlight, but the moths are the first known invertebrates, or creatures without a backbone, to find their way across such long distances using the stars.
'The moths really are using a view of the night sky'
Scientists have long wondered how the moths travel to a place they've never been. A previous study hinted that Earth's magnetic field might help steer them in the right direction, along with some kind of visual landmark as a guide.
Since stars appear in predictable patterns each night, scientists suspected they might help lead the way. They placed moths in a flight simulator that mimicked the night sky above them and blocked out the Earth's magnetic field, noting where they flew. Then they scrambled the stars and saw how the moths reacted.
When the stars were as they should be, the moths flapped in the right direction. But when the stars were in random places, the moths were disoriented. Their brain cells also got excited in response to specific orientations of the night sky.
The findings were published Wednesday in the journal Nature.
It 'was a very clean, impressive demonstration that the moths really are using a view of the night sky to guide their movements,' said Kenneth Lohmann, who studies animal navigation at the University of North Carolina at Chapel Hill and was not involved with the new research.
Do other animals use the night sky to navigate?
Researchers don't know what features of the night sky the moths use to find their way. It could be a stripe of light from the Milky Way, a colourful nebula or something else entirely.
Whatever it is, the insects seem to rely on that, along with Earth's magnetic field, to make their journey.
Other animals harness the stars as a guide. Birds take celestial cues as they soar through the skies, and dung beetles roll their remains short distances while using the Milky Way to stay on course.
It's an impressive feat for Bogong moths, whose brains are smaller than a grain of rice, to rely on the night sky for their odyssey, said study author David Dreyer with Lund University in Sweden.
'It's remarkable that an animal with such a tiny brain can actually do this,' Dreyer said.
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Euronews
5 hours ago
- Euronews
This moth uses the stars to navigate on its epic 1,000 km migration
An Australian moth follows the stars during its yearly migration, using the night sky as a guiding compass, according to a new study. When temperatures heat up, nocturnal Bogong moths fly about 1,000 kilometres to cool down in caves by the Australian Alps. They later return home to breed and die. Birds routinely navigate by starlight, but the moths are the first known invertebrates, or creatures without a backbone, to find their way across such long distances using the stars. 'The moths really are using a view of the night sky' Scientists have long wondered how the moths travel to a place they've never been. A previous study hinted that Earth's magnetic field might help steer them in the right direction, along with some kind of visual landmark as a guide. Since stars appear in predictable patterns each night, scientists suspected they might help lead the way. They placed moths in a flight simulator that mimicked the night sky above them and blocked out the Earth's magnetic field, noting where they flew. Then they scrambled the stars and saw how the moths reacted. When the stars were as they should be, the moths flapped in the right direction. But when the stars were in random places, the moths were disoriented. Their brain cells also got excited in response to specific orientations of the night sky. The findings were published Wednesday in the journal Nature. It 'was a very clean, impressive demonstration that the moths really are using a view of the night sky to guide their movements,' said Kenneth Lohmann, who studies animal navigation at the University of North Carolina at Chapel Hill and was not involved with the new research. Do other animals use the night sky to navigate? Researchers don't know what features of the night sky the moths use to find their way. It could be a stripe of light from the Milky Way, a colourful nebula or something else entirely. Whatever it is, the insects seem to rely on that, along with Earth's magnetic field, to make their journey. Other animals harness the stars as a guide. Birds take celestial cues as they soar through the skies, and dung beetles roll their remains short distances while using the Milky Way to stay on course. It's an impressive feat for Bogong moths, whose brains are smaller than a grain of rice, to rely on the night sky for their odyssey, said study author David Dreyer with Lund University in Sweden. 'It's remarkable that an animal with such a tiny brain can actually do this,' Dreyer said.
France 24
4 days ago
- France 24
Moth uses stars to navigate long distances, scientists discover
When temperatures start rising every year, Bogong moths embark on the long night-time flight from their home on the country's eastern coast to the cool inland shelter of caves in the Australian Alps. It has recently been discovered that they can use Earth's magnetic field like a compass to stay on track during their trip of up to 1,000 kilometres (620 miles). Now, a study published in the journal Nature has found that the moths can also use the light from the stars and the Milky Way to find their way through the dark. "This is the first invertebrate that's known to be able to use the stars for that purpose," study co-author Eric Warrant of Sweden's Lund University told AFP. The only other invertebrate known to use stars for orientation are dung beetles -- but that is over very short distances, Warrant said. Out of all the animal kingdom, only some birds, possibly seals and of course humans can use starlight to navigate long distance. Bogong moths, which are around three centimetres long and are named after the Indigenous Australian word for brown, now join that list. 'Flight simulator' To study this phenomenon, the international team of researchers put some Bogong moths in a small enclosure and projected different maps of the night sky onto its ceiling. The moth was tethered to a rod connected to the top of the enclosure, which precisely recorded which directions it tried to fly in. This "flight simulator" first confirmed that Bogong moths can in fact navigate using their internal magnetic compass, lead study author David Dreyer, also of Lund University, told AFP. Then the researchers removed the effect of Earth's magnetic field in the enclosure. "To our surprise," the moths were still able to find the right direction, Dreyer said. When they rotated the sky 180 degrees, the moths changed their flight to follow along. And when the researchers projected weird, incorrect maps of the night sky, the moths became erratic and lost. This reinforced that the insects can not only navigate by the sky, but can follow along during the night when the relative positions of the stars shift along with Earth's rotation. Mysteries abound No one knows exactly how the Bogong moth manages this feat. One theory is that they sometimes "cross-check" their direction with their magnetic compass, Dreyer said. Another question is exactly which stars the moths are using to navigate. In the lab, the researchers monitored 30 neurons involved in the moth's vision, coordination and navigation. Developing the system of non-magnetic electrodes "cost me a fortune but it was worth the investment," Warrant said. The neurons became particularly active at the sight of the long, bright stripe of the Milky Way, as well as the Carina Nebula. The Milky Way is brighter in the Southern Hemisphere than in the north, Warrant pointed out. "The intensity of that stripe grows as you go from the northern part of the sky to the southern part," which could offer a clue as to how the moths use it to navigate south, Warrant said. Another mystery is how the moths know when to head south when summer arrives. Warrant, who is supervising further research on this subject, said one option is that this knowledge was simply "something that the parents hand to their children". The researchers believe that near the end of the moth's long migration, they start noticing clues they are getting close to their mountain refuge. Warrant said he has identified a specific "odour compound" which emanates from the caves. This smell "seems to act as a navigational beacon right at the very end of the journey," he added. After the moths have seen out the sweltering summer, they return to their coastal birthplace to reproduce before dying. © 2025 AFP
France 24
4 days ago
- France 24
Climate change could cut crop yields up to a quarter
As soon as 2050, this "moderate" scenario in which greenhouse gas emissions peak around 2040 and slowly taper off -- a trajectory aligned with current trends -- would see global losses of nearly eight percent. And if carbon pollution worsens, the loss of calories across the same six staples -- corn, wheat, rice, soybeans, sorghum and cassava -- rises to nearly a quarter by century's end, the researchers reported in Nature. More generally, every additional degree Celsius of warming reduces the world's ability to produce food from these crops by 120 calories per person per day, or nearly five percent of current daily consumption, they calculated. "If the climate warms by three degrees, that's basically like everyone on the planet giving up breakfast," said co-author Solomon Hsiang, a professor at the Stanford Doerr School of Sustainability in California. The steepest losses will occur at the extremes of the agricultural economy: in modern, Big Ag breadbaskets that currently enjoy some of the world's best growing conditions, and in subsistence farming communities that typically rely of small cassava harvests. North America would be hit hardest, losing a fifth of yields by 2100 in the moderate carbon pollution scenario, and two-fifths if emissions from burning fossil fuels continue apace. Working with more than a dozen scientists, Hsiang and co-leader Andrew Hultgren, an assistant professor at the University of Urbana-Champaign, sifted through data from more than 12,000 regions in 55 countries. Erratic weather Previous calculations of how a warming world will impact crop yields generally failed to consider the ways in which farmers would adapt, such as switching crop varieties, shifting planting and harvesting dates, and altering fertiliser use. The scientists estimated such adjustments would offset about a third of climate related losses over the next 75 years in the scenario of rising emissions, but that residual impacts would still be devastating. "Any level of warming, even when accounting for adaptation, results in global output losses for agriculture," said Hultgren. With the planet about 1.5C hotter than preindustrial levels in the late 1900s, farmers in many regions are already experiencing longer dry spells, unseasonable heatwaves and erratic weather that undermines yields. The nutritional value of most crops also declines with hotter temperatures, earlier research has shown. The study revealed sharp variations in the impact of global warming on different crops and regions. In the "worst-case" scenario of rising carbon emissions, corn yields would plummet 40 percent by 2100 across the grain belt of the United States, eastern China, central Asia, and the Middle East. For soybeans, yields in the US would decline by half, and increase by a fifth in Brazil. Wheat losses would drop by a fifth in eastern and western Europe, and by 30 to 40 percent in other wheat-growing regions: China, Russia and North America. Cassava would be hit hard everywhere it's grown. "Although cassava does not make up a large portion of global agricultural revenues, it is an important subsistence crop in low- and middle-income countries," the researchers pointed out. Among the six crops examined, rice is the only one that stands to benefit in a warmer climate, mainly due to warmer nights. © 2025 AFP
