Nav: Home

Watch: Insects also migrate using the Earth's magnetic field

June 21, 2018

A major international study led by researchers from Lund University in Sweden has proven for the first time that certain nocturnally migrating insects can explore and navigate using the Earth's magnetic field. Until now, the ability to steer flight using an internal magnetic compass was only known in nocturnally migrating birds.

WATCH: The incredible journey of the bogong moth https://www.youtube.com/watch?v=Z7w44Ka0xXI

"Our findings are the first reliable proof that nocturnally active insects can use the Earth's magnetic field to guide their flight when migrating over one thousand kilometres. We show that insects probably use the Earth's magnetic field in a similar way to birds", says Eric Warrant, professor at Lund University.

Eric Warrant and David Dreyer at Lund University, together with colleagues from Australia, Canada, Germany, and the USA , studied the moth species Agrotis infusa, also known as the Bogong moth, in Australia.

The findings indicate that the insects use both visual landmarks in their flight path and the Earth's magnetic field, probably making their navigation more reliable.

The researchers believe that moths in northern Europe may use the Earth's magnetic field in an equivalent manner when flying over the Alps to the Mediterranean.

The moths migrate over a great distance every year, from a large area in southeastern Australia to a specific area of small, cool caves high up in the mountains more than one thousand kilometres away. After a few months in a dormant state, they make the same journey back when summer is over. Besides the Bogong moth, only the North American Monarch butterfly migrates with equivalent precision.

The researchers focused on investigating how the Bogong moth knows in which direction to fly. They found answers by capturing the moths in flight and placing them in a flight simulator where the insects were free to fly in any direction they chose. The flight simulator - invented by team members Barrie Frost and Henrik Mouritsen for studying navigation in Monarch butterflies - was in turn placed in a system of magnetic coils which allowed the researchers to turn the magnetic field in any direction. In addition, they were able to show visual landmarks to the moths.

"By turning the magnetic field and the landmarks either together or in conflict with each other, we were able to investigate how the Bogong moths use magnetic and visual information to direct their flight", says David Dreyer, adding:

"When the magnetic field and the landmarks were turned together, the moths changed their flight path in an equivalent manner. However, if the magnetic field and the landmarks were turned in conflict with each other, the moths lost their sense of direction and became confused."

Eric Warrant has many years of experience of researching animal night vision and how animals navigate in the dark. Nevertheless, the findings surprised him.

"I believed the studies would show that Bogong moths only use visual cues such as stars, the moon and landmarks to navigate. But that is not the case. They perceive the Earth's magnetic field in exactly the same way as birds do - and probably for the same reason."

The next step will be to find out how the moths, despite never having been to the caves before, know that they have arrived at their destination. The researchers also want to locate and characterise the insects' elusive magnetic sensor.
-end-
Besides Lund University, the following higher education institutions and organisations took part in the research work: Queens University in Canada, University of Oldenburg in Germany, Duke University, USA, New South Wales National Parks and Wildlife Service and the Australian Cotton Research Institute, both in Australia.

For raw video material or more images, please contact the press office.

For journalists interested in covering the team's upcoming field work in Australia, please contact Eric Warrant directly or the press office.

Lund University

Related Magnetic Field Articles:

Understanding stars: How tornado-shaped flow in a dynamo strengthens the magnetic field
A new simulation based on the von-Kármán-Sodium (VKS) dynamo experiment takes a closer look at how the liquid vortex created by the device generates a magnetic field.
'Quartz' crystals at the Earth's core power its magnetic field
Scientists at the Earth-Life Science Institute at the Tokyo Institute of Technology report in Nature (Fen.
Brightest neutron star yet has a multipolar magnetic field
Scientists have identified a neutron star that is consuming material so fast it emits more x-rays than any other.
Confirmation of Wendelstein 7-X magnetic field
Physicist Sam Lazerson of the US Department of Energy's Princeton Plasma Physics Laboratory has teamed with German scientists to confirm that the Wendelstein 7-X fusion energy device called a stellarator in Greifswald, Germany, produces high-quality magnetic fields that are consistent with their complex design.
High-precision magnetic field sensing
Scientists have developed a highly sensitive sensor to detect tiny changes in strong magnetic fields.
Brilliant burst in space reveals universe's magnetic field
Scientists have detected the brightest fast burst of radio waves in space to date -- locating the source of the event with more precision than previous efforts.
Optical magnetic field sensor can detect signals from the nervous system
The human body is controlled by electrical impulses in the brain, the heart and nervous system.
What did Earth's ancient magnetic field look like?
New work from Carnegie's Peter Driscoll suggests Earth's ancient magnetic field was significantly different than the present day field, originating from several poles rather than the familiar two.
Just what sustains Earth's magnetic field anyway?
Earth's magnetic field shields us from deadly cosmic radiation, and without it, life as we know it could not exist here.
Ironing out the mystery of Earth's magnetic field
The Earth's magnetic field has been existing for at least 3.4 billion years thanks to the low heat conduction capability of iron in the planet's core.

Related Magnetic Field Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Bias And Perception
How does bias distort our thinking, our listening, our beliefs... and even our search results? How can we fight it? This hour, TED speakers explore ideas about the unconscious biases that shape us. Guests include writer and broadcaster Yassmin Abdel-Magied, climatologist J. Marshall Shepherd, journalist Andreas Ekström, and experimental psychologist Tony Salvador.
Now Playing: Science for the People

#514 Arctic Energy (Rebroadcast)
This week we're looking at how alternative energy works in the arctic. We speak to Louie Azzolini and Linda Todd from the Arctic Energy Alliance, a non-profit helping communities reduce their energy usage and transition to more affordable and sustainable forms of energy. And the lessons they're learning along the way can help those of us further south.