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Ocean-Crossing Dragonflies Discovered

Posted by samzenpus on from the incredible-journey dept.

grrlscientist writes "While living and working as a marine biologist in Maldives, Charles Anderson noticed sudden explosions of dragonflies at certain times of year. He explains how he carefully tracked the path of a plain, little dragonfly called the Globe Skimmer, Pantala flavescens, only to discover that it had the longest migratory journey of any insect in the world."

12 of 95 comments (clear)

  1. Impressive... by fuzzyfuzzyfungus · · Score: 4, Insightful

    There just isn't much room for energy storage inside a dragonfly. They must have commendably efficient ways of staying in the air, presumably a combination of powered flight and exploitation of available air currents.

    It would be interesting to know what percentage of them survive.

    1. Re:Impressive... by TheGratefulNet · · Score: 4, Funny

      ...or ability to harness solar energy ;)

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    2. Re:Impressive... by wizardforce · · Score: 4, Informative

      TFA has a video that explains quite a bit about the species and one of the interesting things about it is that the dragonfly cruses at an altitude of 1-2 km over the surface. They migrate in order to catch the rainy season of East Africa and India. The winds at this altitude move toward the rainy areas due to meteorological effects so they do make use of air currents.

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    3. Re:Impressive... by criminy · · Score: 5, Funny

      400 miles is about 640,000 meters

      640k should be enough for anyone.

    4. Re:Impressive... by edman007 · · Score: 5, Informative

      When you are small and light it is not actually required that you expel energy to float, the turbulence in the air can keep you going to a very long time for example water can stay in a cloud long enough to become softball sized hail and a glider can stay in the air all day, the energy is technically wind energy derived from solar and it is not coming from the object flying.

    5. Re:Impressive... by RuBLed · · Score: 5, Funny

      It can be explained, consider a spherical dragonfly in a vacuum...

    6. Re:Impressive... by cowboy76Spain · · Score: 4, Insightful

      Well... they are insects, so their strategy is usually based in numbers. Maybe only 1 in 5 dragonflies (warning, numbers made up) get to end the travel safely; that would be unacceptable for men or other animals that take years to mature but for insects could be reasonable.

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  2. TED by Anonymous Coward · · Score: 4, Informative

    http://www.ted.com/talks/charles_anderson_discovers_dragonflies_that_cross_oceans.html

  3. Name by treeves · · Score: 4, Insightful

    Was it called the Globe Skimmer before his discovery? If so, it was quite a prescient name.

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    1. Re:Name by courseofhumanevents · · Score: 5, Funny

      I don't think it was called anything before it was discovered, actually.

    2. Re:Name by edman007 · · Score: 5, Informative

      According to the wikipedia:

      Pantala flavescens, the Globe Skimmer or Wandering Glider, is a wide-ranging dragonfly of the family Libellulidae. This species and Pantala hymenaea, the "Spot-winged Glider", are the only members of the genus Pantala from the subfamily Pantalinae. It was first described by Fabricius in 1798.[1] It is considered to be the most widespread dragonfly on the planet.

      The English common names "Wandering Glider" and "Globe Skimmer" refer to its migratory behaviour.[3] The German name Wanderlibelle mean "migrant dragonfly". In Hong Kong, its name translates as Typhoon Dragonfly as it arrives with or shortly before the seasonal rain.

      http://en.wikipedia.org/wiki/Globe_Skimmer

      It seems to me that it has been known that it just seems to "show up" at specific times of the year and does migrate, but nobody knew just how far it really did migrate.

  4. They've always been ocean crossing... by tompaulco · · Score: 4, Funny

    ...but up until now the scientific tracking tools were too heavy and the dragonflies all fell into the ocean and drowned. Why, it was only 10 years ago that advances in tracking devices caused scientists to discover that dragonflies could actually fly.

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