To facilitate discussion, we are publishing the abstracts and conclusions/summaries of the 24 papers from the Cornell Conference on the Origin of Biological Information here at Uncommon Descent, with cumulative links to previous papers at the bottom of each page.
Here’s part of the summary of “Tierra: The Character of Adaptation” by Winston Ewert, William A. Dembski, and Robert J. Marks II:
The author of Tierra sought to create a digital Cambrian explosion whereby the power of the evolutionary process was unleashed. It is agreed that Tierra did not succeed in accomplishing this feat. Rather, the evolutionary activity within Tierra dies after only a transitory period. No Cambrian explosion occurs.
Furthermore, the evolutionary activity that occurred was not of the sort that can be used as the basis for the ongoing evolution of novel information. Most change in Tierra was created by rearranging the existing code in the system, not by producing new code. Some cases did produce new code; however, the amount of change produced in this fashion is very small compared to change produced in other ways. What information gain existed only manages to tweak the existing system. The trajectory of Tierra was wrong, it is dominated by the wrong category of adaptation.
The observation that evolution consists largely of adaptations that remove or manipulate existing information, rather than adaptations producing new information, is not restricted to Tierra. Many observed adaptations in biology are in fact derived from changes which break existing systems [23]. Studies of biological adaptations have shown that they proceed via the elimination of unnecessary and costly functions [24,25]. A survey of lab experiments showed that the adaptations found in such scenarios fit the same picture [26]. Further discussion of adaptation by loss in biological scenarios can be found within these proceedings [27].
Unlike many artificial life simulations, Tierra followed Darwinism by not imposing an external artificial fitness. Tierran programs were not rewarded for performing calculations or solving problems. Rather in Tierra there was only survival and replication. As a result Tierra paralleled biology more closely on this
point. As discussed, the pattern of observed adaptation is similar between Tierra and biology. Rather than being a system which fails to imitate biology closely enough to produce a Cambrian explosion, Tierra is a system which manages to imitate the character of directly observed biological adaptations.
The paper goes on to talk about the Avida program.
See also: Origin of Biological Information conference: Its goals
Open Mike: Origin of Biological Information conference: Origin of life studies flatlined
Open Mike: Cornell OBI Conference— Can you answer these conundrums about information?
Open Mike: Cornell OBI Conference—Is a new definition of information needed for biology? (Chapter 2)
Open Mike: Cornell OBI Conference—New definition of information proposed: Universal Information (Chapter 2)
Open Mike: Cornell OBI Conference—Chapter Three, Dembski, Ewert, and Marks on the true cost of a successful search
Open Mike: Cornell OBI Conference—Chapter Three on the true cost of a successful search—Conservation of information
Open Mike: Cornell OBI Conference—Chapter Four: Pragmatic Information
Open Mike: Cornell OBI Conference—Chapter Four, Pragmatic information: Conclusion
Open Mike: Cornell OBI Conference Chapter Five Abstract
Open Mike: Cornell OBI Conference Chapter Five – Basener on limits of chaos – Conclusion
Open Mike: Cornell OBI Conference Chapter Six – Ewert et all on the Tierra evolution program – Abstract