However metamorphosis evolved, the enormous numbers of metamorphosing insects on the planet speak for its success as a reproductive strategy. The primary advantage of complete metamorphosis is eliminating competition between the young and old. Larval insects and adult insects occupy very different ecological niches. Whereas caterpillars are busy gorging themselves on leaves, completely disinterested in reproduction, butterflies are flitting from flower to flower in search of nectar and mates. Because larvas and adults do not compete with one another for space or resources, more of each can coexist relative to species in which the young and old live in the same places and eat the same things. Ultimately, the impetus for many of life's astounding transformations also explains insect metamorphosis: survival.
Subscription Center
Rights & Permissions
See what we're tweeting about
31 Comments
Add CommentI put my money on either one of TWO advantages:
Reply | Report Abuse | Link to this1. It was/is a means of avoiding some predation.
2. It was/is a better means of propagation.
These are two of the most powerful evolutionarily successful mechanisms on the planet.
Very interesting!
Reply | Report Abuse | Link to thisHow might the process of molting be related to metamorphosis?
pfff. you lazy, breh.
Reply | Report Abuse | Link to thisWhat is truly embarrassing is the COMPLETELY unfounded [except by blind belief] of those who would accept such a foolish concept as "intelligent design". If ever there was a misnomer it is that term "intelligent" ... You have "INHERITED THE WIND", Gatnos. And the wind has blown from those who rely on ancient texts from superstitious generations of millennia ago. You would do yourself a favor by looking into the myriad bases of evidence which support the well-established theory of Evolution. You also give it away that you don't know what is meant in science by the term "theory". It's always better to find out what you don't know before you expose your ignorance in what you say.
Reply | Report Abuse | Link to thisRe: "Perhaps this pro-nymphal stage, Riddiford and Truman suggest, evolved into the larval stage of complete metamorphosis. Perhaps 280 million years ago, through a chance mutation, some pro-nymphs failed to absorb all the yolk in their eggs, leaving a precious resource unused."
Reply | Report Abuse | Link to thisPerhaps would seem to be an expression of caution. Yet, the process is touted as having been established as plausible based on the combined fossil evidence and subsequent studies.
My understanding is that the vast majority of mutations is neutral at best, deleterious at worst. What is an example of a beneficial mutation which could have been responsible for metamorphosis?
A mutation that prevented the juvenile hormones from being turned off early. While all the other bugs were growing to adult hood and competing for food, the mutant would still be a juvenile and without competition. The longer they wait to turn off those hormones the less competition they have for the resources they require.
Reply | Report Abuse | Link to this"Perhaps would seem to be an expression of caution. Yet, the process is touted as having been established as plausible based on the combined fossil evidence and subsequent studies."
Reply | Report Abuse | Link to thisThat's how science works. Evidence and the results of research suggest likely mechanisms, until further evidence or different research provides more support for or overthrows those earlier ideas.
So not even gonna try and understand it, just "God did it" and that's it. How simple your world must be.
Reply | Report Abuse | Link to thisHaving 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.
Reply | Report Abuse | Link to thisNow of course this is how Science works and it is perfectly acceptable as a vague theory. But SciAm is presenting is for what it is not. Metamorphosis is indeed a mysterious process and in my mind it remains a great mystery.
"Ultimately, the impetus for many of life's astounding transformations also explains insect metamorphosis: survival."
ALL evolution is driven by survival. This is a meaningless statement.
"The primary advantage of complete metamorphosis is eliminating competition between the young and old. "
As a theory this seems rather weak to me. It is also weak because there is no evidence for it. It is an interesting postulation, but that is all.
Observe the life cycle of Magicicadae to support this observation.
Reply | Report Abuse | Link to thisThis is a very interesting article. Wow, 65% of all organisms are metamorphosing. Human is in the 35%. I just wonder if human do metamorphosis, perhaps alien-like? =D
Reply | Report Abuse | Link to thisGatnos ,
Reply | Report Abuse | Link to thisThere is one good thing about your belief, it avoids that difficult thing called thinking.
Zexks (comment 7),
Reply | Report Abuse | Link to thisHas any researcher identified the mutation?
marleysdaddy (comment 8),
Reply | Report Abuse | Link to thisIt's quite clear how the brand of science presented on this web page works. Assertions (i.e., "evidence from the fossil record with studies on insect anatomy and development") have been presented as positive arguments. What fossil evidence combined with what subsequent studies have made the assertions plausible?
This is an article presenting a hypothesis that is supported by a research report published under the heading "Hypothesis" in a peer reviewed scientific publication, referenced in this article:
Reply | Report Abuse | Link to thisJames W. Truman & Lynn M. Riddiford, (1999), "The origins of insect metamorphosis",
http://www.nature.com/nature/journal/v401/n6752abs/401447a0.html
Also see the referenced freely available open access research report:
Deniz F. Erezyilmaz, (2006), "Imperfect eggs and oviform nymphs: a history of ideas about the origins of insect metamorphosis",
http://intl-icb.oxfordjournals.org/content/46/6/795.full
Your first reference is broken - but your second is interesting, though 6 years old, and makes me wonder why it was not referenced in the article above ?
Reply | Report Abuse | Link to thisI agree. No references to any evidence to support his article and a thoroughly subjective piece of journalism.
Reply | Report Abuse | Link to thisHis dismissive attitude to Donald Williamson's idea as "outlandish" is really quite appalling considering we are discussing metamorphosis, an outlandish biological process in and of itself ...
Regrettably this is part of the general trend in SciAm which has drifted away from Science and into the world of the tabloid more and more in recent years.
Thanks for pointing out my error. This should be the correct link (with the missing slash):
Reply | Report Abuse | Link to thishttp://www.nature.com/nature/journal/v401/n6752/abs/401447a0.html
Actually, both research reports are referenced by dynamic links within this article; the first near the beginning of para. 2 under the heading "A new generation" ("... constructed one of the most comprehensive theories"); the second in the forth para. under the same heading ("... supports this evolutionary scenario").
"It is an interesting postulation, but that is all."
Reply | Report Abuse | Link to thisSo now, sleeves up and searching for more evidence. They have shown that metamorphosis could enhance survival. I find that very convincing, for the time being. I'm waiting for somebody who can falsify this.
jtdwyer (comment 16),
Reply | Report Abuse | Link to thisRe: http://www.nature.com/nature/journal/v401/n6752abs/401447a0.html
Entering that url resulted in the following message:
Error: page not found
You might not be able to find the page you are looking for because of an out of date bookmark/favourite, or possibly a mis-typed address (in which case it may be worth trying again).
If retyping the address still doesn't work, try using our search to find the page you want. Alternatively browse our sites using the list below:
That, in itself, is not of any particular concern. My experience has been the online copies of papers from NATURE are only available to me at unacceptable cost.
Re: http://intl-icb.oxfordjournals.org/content/46/6/795.full
A cursory review of this paper indicates it's nothing more than a history lesson. Is there anything in particular on which you would like me to focus?
HowardB (comment 18),
Reply | Report Abuse | Link to thisMy guess is, Donald Williamson's proposal is no more acceptable to me than any of the other proposals thus far presented.
No, I've got nothing in particular or in general to present or propose to you - certainly nothing that could possibly be acceptable to you.
Reply | Report Abuse | Link to thisMetamorphosis. The adaptation in ability to build an organic scaffolding in different forms of complexity unfolding in growth as in origami
Reply | Report Abuse | Link to this"Actually, both research reports are referenced by dynamic links within this article"
Reply | Report Abuse | Link to thisYou are correct. My error. However I remain critical because I find this dynamic reference habit inadequate. An article should have it's academic references at the end of the article or explicitly stated within the article. Dynamic links are fine with background information or other SciAm articles. That is how I see it anyway.
20. ridelo:
Reply | Report Abuse | Link to this"So now, sleeves up and searching for more evidence. They have shown that metamorphosis could enhance survival. I find that very convincing, for the time being. I'm waiting for somebody who can falsify this."
That is fine ! that is how Science works. But you don't make an announcement that the explanation has been found, which is the implication of the article headline.
IMO, you're being overly critical here. The title simply asks the question without making any proclamations. The subtitle states that "metamorphosis remains somewhat mysterious" but adds, "biologists have gathered enough evidence to _plausibly_ explain..." This hardly seems to be a definitive announcement, but one appropriate for a fairly recent hypothesis that, after several years has not been denounced by peer review.
Reply | Report Abuse | Link to thisI certainly agree the SA is often guilty of overstatement and hyperbole, especially in their titles, but this case seems appropriately stated to me...
That being said, looking back at the article link caption on the SA home page: "Origin of Insect Metamorphosis Explained" - I wholeheartedly agree with your assessment!
Reply | Report Abuse | Link to this27. jtdwyer
Reply | Report Abuse | Link to thisI do take your point about being over critical. I guess I expect a bit more from SciAm than from the NYT or from a tabloid reporting on Science.
I also think this Metamorphosis thing is an absolutely fascinating process, and a prime topic for an extended section in SciAm
"Larval insects and adult insects occupy very different ecological niches. "
Reply | Report Abuse | Link to thisCouldn't the same be said for human children who have a more delayed maturation? Or, do insects that undergo metamorphosis lead more complex adult lives--genetic memory is preserved with this type of growth (butterflies). Again, somewhat similar to human children who develop more complex brains.
I agree - an excellent suggestion!
Reply | Report Abuse | Link to thisThe adaptation in ability for building an organic scaffolding in different forms of complexity unfolding in growth as in origami.
Reply | Report Abuse | Link to this