Making new evolutionary innovations (Introduction)

by dhw, Saturday, November 23, 2019, 10:22 (420 days ago) @ David Turell

DAVID: A study plays with genes and makes forms change:

QUOTES: "When studying how organisms evolve, biologists consider most traits, or features, as derived from some earlier version already present in their ancestors. Few traits are regarded as truly "novel."

And in biology textbooks, novelty has a strict definition: it must have no relationship to any structure found in an ancestor and no relationship to any other body part elsewhere in the organism. By this definition, a dolphin's pectoral fins are not a novelty because they are modified forelimbs that already existed.

"'This work forces us to rethink what we mean by 'novelty'", Moczek said. "Each insect segment possesses this gene network, and as such, it is an ancient feature of their makeup. Yet, what each segment does with this network is so strikingly variable that it can yield traits that on the surface seem to have nothing in common, like wings and horns."

"'This new evidence is profound since it suggests that all of this vast diversity, all these novelties, could in fact be enabled by a single gene network that was used millions of years ago to form the flight wings on other body segments.'"

DAVID: This did not occur to the scientists, but they acted like God in what they produced in the changes they made. Not new species but large modifications. It fits my concept of God's preplanning an easy way to run evolution.

Thank you for this very important article, which both reinforces and explains my own insistence that we cannot draw a firm borderline between adaptation and innovation. (The dolphin example exactly mirrors our own example of the whale.) More importantly, it explains how common descent proceeds – there is some mechanism within the genes (which we may define as “the fundamental units of inheritance and function in a cell”) which enables them to change so radically that they can produce what appears to be every “evolutionary novelty” (Shapiro) leading to speciation. The scientists have simply induced a process which may be perfectly natural. But yes, common descent fits your theory of 3.8 billion years' worth of computer programming as it does Shapiro’s (and my) concept of intelligent cells/cell communities designing their own innovations. The latter theory does not, however, cover the possible origin of the mechanism, which may or may not be your God.

Complete thread:

 RSS Feed of thread

powered by my little forum