Sentences with word «exaptation»

But to truly assess the role of exaptation in evolution, they will need to validate their results in living organisms.
The strength of Barve and Wagner's theoretical approach was that they could definitely demonstrate the potential for exaptation outside of any historical context.
A new study in Nature offers what may be the first attempt to comprehensively identify potential exaptations.
Birds» and bats» wings could be called exaptations of arms; however, the structural changes that followed can not be called adaptations because «you are talking about a historical incident; it's not something you can test,» said Mark Norell, a vertebrate paleontologist at the American Museum of Natural History, who studied with Vrba.
I see a variety of «improbability» calculations thrown up by ID / creationists, but they invariably seem to misrepresent what the science indicates, e.g. requiring the final product be produced at once, ignoring exaptation, etc..
At the heart of your Behe article are two concessions which simply don't support ID: 1) the ability of evolution to produce functional novelty via gene duplication / mutation and exaptation exists; and 2) that evidence of «new information» in the form of «new Functional Coded elemenTs, or «FCTs»» also exists.
The results of the study, which focused on metabolism, complement anecdotal examples and take an initial step toward quantifying exaptation's contribution, at least within this system, said researchers not involved in the work.
Barve and Wagner's work adds to a growing number of examples of exaptation at the molecular level.
He and his colleagues identify a decline in the use of exaptation relative to adaptation in evolutionary biology literature and blame the trend on the lack of a clear distinction; they propose redefining the term.
While exaptations are traits that have been enlisted for new uses, adaptations have been shaped by natural selection for their current function, they wrote.
Shifting the Balance The metabolism study suggests that a healthy portion of novel traits get their start as exaptations.
Instead, the complexity of the network appeared to determine its flexibility; the more reactions in a network, the greater its potential for exaptation.
A computational study reveals surprising flexibility hidden within metabolic networks, providing new evidence for an evolutionary concept called exaptation
In other words, one adaptation (viability on glucose) was accompanied by multiple potential exaptations.
The scientists conclude that this is probably an example of exaptation — when a structure that was meant for one function is co-opted for another.
Seeking Hidden Potential Identifying an exaptation requires a look back at history, which is not easy to do with most biological traits.
«I think it's becoming increasingly clear that exaptation is very important in the evolution of biologically important processes,» said Joe Thornton, a molecular evolutionary biologist at the University of Chicago and the University of Oregon, who was not involved in the study.
«If that was the only explanation for the incidence of exaptation, that would not be interesting,» Wagner said.
However, some counter that exaptation and adaptation are indeed distinct, meaningful phenomena, although the distinction can be subtle.
As they described it, exaptation is a counterpart to the more familiar concept of adaptation.
In 1982, Stephen Jay Gould and Elisabeth Vrba gave a name to this phenomenon: exaptation.
In this scenario, that capacity to switch fuels gives rise to an exaptation.
The concept has been controversial since it first arose, largely because it has been so difficult to distinguish between the forces of exaptation and adaptation in the historical context of evolution.
The order and arrangement of the bones in the four limbs of land - dwelling animals are an exaptation for walking on land, since these limbs originally evolved for navigating water; by contrast, changes to the shape of the bones and to the musculature are adaptations, Gould and Vrba wrote.
Even prior to this study, the two concepts — adaptation versus exaptation (drawn from nonadaptive traits or traits adapted for another purpose)-- were difficult to separate.
On the other hand, if a hormone once in charge of regulating one process is co-opted to regulate a second process, that is an exaptation because the hormone did not evolve by natural selection to regulate the second process.
Others, however, say it's impossible to distinguish adaptation from exaptation, rendering Gould and Vrba's definition of exaptation redundant.
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