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Researchers claim to have solved problem of insect metamorphosis

Here.

By combining evidence from the fossil record with studies on insect anatomy and development, biologists have established a plausible narrative about the origin of insect metamorphosis, which they continue to revise as new information surfaces. The earliest insects in Earth’s history did not metamorphose; they hatched from eggs, essentially as miniature adults. Between 280 million and 300 million years ago, however, some insects began to mature a little differently—they hatched in forms that neither looked nor behaved like their adult versions. This shift proved remarkably beneficial: young and old insects were no longer competing for the same resources. Metamorphosis was so successful that, today, as many as 65 percent of all animal species on the planet are metamorphosing insects. – “How Did Insect Metamorphosis Evolve?”, Scientific American, August 10, 2012

The comments are the real story in this case. Note especially comment 10:

Having read this article three times I see no ‘explanation’. I simply see a series of observations tied together and set out as a broad rather vague theory.

One problem that seems apparent to the News desk around here is that the claim that “ young and old insects were no longer competing for the same resources” is nonsense.

Adult insects often do not live very long. Some hardly eat. Some don’t even have mouth parts. They mate and die.

And , to continue the species, they must lay eggs that produce young that are competing for the same resources with the young of many other insects, of their own species and others. So it is not clear just what food problem metamorphosis is supposed to have solved. What metamorphosis mainly does is enable the insect to travel easily to find a mate — something the wingless larva would be generally less able to do, left to its own devices. We still have no idea why it all happened this way.

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2 Responses to Researchers claim to have solved problem of insect metamorphosis

  1. //Having read this article three times I see no ‘explanation’. I simply see a series of observations tied together and set out as a broad rather vague theory.//

    LOL

    Wow, didn’t realize so many species were metamorphosing insects! :>

  2. as to:

    Between 280 million and 300 million years ago, however, some insects began to mature a little differently

    As far as the fossil record can tell us, up to 370 mya insects with the ability to undergo ‘complete metamorphosis’ appeared abruptly with the signature complex larval stage indicative of ‘complete metamorphosis’ already present from the very beginning of their existence on earth:

    Humble bug plugs gap in fossil record – August 2012
    Excerpt: One day 370 million years ago, a tiny larva came to a sticky end when it plunged into a shrimp-infested swamp and drowned.,,
    Named Strudiella devonica, the eight-millimetre invertebrate – while in far from mint condition – is thought,, to be the world’s oldest complete insect fossil.
    http://www.news24.com/SciTech/.....d-20120801

    Moreover, apparently unbeknownst to these researchers, metamorphosis was present in the Cambrian:

    The Enigma of Metamorphosis Is Hardly Limited to Butterflies – October 2011
    Excerpt: Even more mysteriously, it appears that the most ancient phyla were metamorphic from the beginning, based on the few larval forms that have been preserved. This suggests that these Cambrian animals had not one but two or more developmental stages at the outset,,,,
    http://www.evolutionnews.org/2.....51541.html

    Metamorphosis Is Widespread – Ann Gauger – video
    http://www.youtube.com/watch?v=GkD-jd1imaI

    further note on complete versus ‘incomplete’ metamorphosis

    Life Cycles of Insects – Metamorphosis – video trailer
    http://video.google.com/videop.....1785656504

    A Mathematician Explains the Irreducible Complexity of Metamorphosis – November 2011
    Excerpt: Now we are not talking about climbing Mount Improbable, we are talking about building a bridge across an enormous chasm, between caterpillar and butterfly. ,, Until construction of this extremely long and complicated bridge is almost complete, it is a bridge to nowhere. Unless a butterfly (or another organism capable of reproduction) comes out at the end, the chrysalis only serves as a casket for the caterpillar, which cannot reproduce. Now we do not have to simply imagine uses for not-quite-watertight vacuum chamber traps, we have to imagine a selective advantage for committing suicide before you are able to reproduce, and that is a more difficult challenge!
    http://www.evolutionnews.org/2.....52461.html

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