| Services |
|
|
|
|
 |
|
| News |
|
|
|
|
|
|
|
|
|
| Channels |
| Home & Family |
|
|
|
|
|
|
|
| Leisure |
|
|
|
|
| Technology |
|
|
|
|
|
| Business |
|
|
|
|
| Science |
|
|
|
|
|
|
|
|
|
|
Site Search  |
|
|
|
|
| Free email |
|
|
|
|
 |
Study reveals insect 'supersociety' |
| TheAllINeed.com |
(NC&T/Cell) In these groups, this question of what drives altruism also becomes critical to further understanding of how ancestral or primitive social organizations (with hierarchies and dominance fights, and a poorly developed division of labor) evolve to become the more highly sophisticated networks found in some eusocial insect collectives called "superorganisms."
In a paper published online May 21 before print by the Proceedings of the National Academy of Sciences (PNAS), a pair of researchers from Cornell University and ASU proposed a model, based on a tug-of-war theory, that may explain the selection pressures that mark the evolutionary transition from primitive society to superorganism – and which may bring some order to the conflicted thinking about the roles of individual, kin and group selection that underlie the formation of such advanced eusocial groups.
A superorganism ultimately emerges as a result of intergroup competition, according to findings by theoretician H. Kern Reeve of Cornell University's Department of Neurobiology and Behavior and professor Bert Hölldobler of ASU's School of Life Sciences and Center for Social Dynamics and Complexity.
Reeve and Hölldobler's model is unique in that it comprises two interlocked, nested tug-of-war theories. The first piece describes the tug-of-war over resources within a group or colony (intragroup competition), and the second piece incorporates the effects of a tug-of-war between competing colonies (intergroup competition).
According to Hölldobler, the path to colonial supergiant is first paved by the maximization of the inclusive fitness of each individual of the society. How this might arise, he believes, is that competition that might exist between individuals in the same society diminishes as the incipient colonial society becomes larger, better organized and contains better division of labor – and, ultimately, better cohesiveness.
 | | Bert Hölldobler. (Photo: ASU) |
"Such societies, in turn, produce more reproductive offspring each year than neighboring societies that are less organized," Hölldobler says. "Thus, genes or alleles that code for such behaviors will be propagated faster."
The second piece of the model takes into account that "as the colonial organization of one group rises, there is a coincident rise in discrimination against members of other societies of the same species."
Hölldobler notes that the competition between societies soon becomes a major force reinforcing the evolutionary process, saying: "In this way, the society or insect colony becomes the extended phenotype of the collective genome of the society."
Hölldobler believes that this model developed with Reeve goes further than others in explaining the evolutionary transition from hierarchical organizations to superorganism, "as it also demonstrates how the target of selection shifts from the individual and kin to group selection," he says.
Such a nested tug-of-war model, he says, might also be applied "equally well to the analysis of the evolution of other animal societies" and give insight into the evolution of cooperation in non-human and human primates, in addition to such things as collectives of cells and the formation of bacterial films.
|
| About the Author |
©2006 All rights reserved
|
|
|
| Quotes | I will not expose the ignorance of the faculty. - Bart Simpson.
I want an Internet. Can I have one of those? -- Spice Girl Mel B.,aka Scary Spice, pointing to a monitor during an AOL press conference
I want to get a tatoo of myself on my entire body, only 2 taller. -- Steven Wright
I think you should defend to the death their right to march, and then go down and meet them with baseball bats.-Woody Allen, on the KKK
|
| Writers | | If you are a writer and want to see your article published at Theallineed.com, just click here to submit. |
|
Poverty reflected in children's schools as well as in the home
Brief description of Tourette syndrome