A "Design Inference" in Science magazine!

In the short article “Middle Stone Age Shell Beads from South Africa” (subscription required), published in tomorrow’s issue of Science magazine, Henshilwood and coworkers report the finding of 41 perforated tick shell beads (from the mollusk Nassarius kraussianus) dated as about 75,000 years old. They provide evidence that the beads are human-made artifacts - the oldest known personal ornaments and a sign of the emergence of symbolic thought in early humans.

Clearly, pace all the ID advocates’ recent claims, upon finding the perforated shells Henshilwood and his colleagues considered “intelligent agency” as a possible cause (perhaps they didn’t know that methodological naturalism supposedly proscribes such consideration, according to Francis Beckwith).

But things only get worse for ID advocates. For their design inference, Henshilwood and colleagues chose - not surprisingly - not to apply Dembski’s “revolutionary” specified complexity criterion (which would go something like: these look like beads, therefore they are specified, and they are improbable, that is “complex”, ergo they are designed), but to rely instead on the good old-fashioned scientific approach.

First, the authors established that the shells likely are actual beads because they display a microscopic wear pattern (likely due to friction) not observed in natural shells, but only in known bead samples. Then they considered the possibility that they may have been carried to the site by animals, and found it unlikely because N. kraussianus’ only known predator is another estuarine gastropod, and because all the shells were from adults (a predation model would have predicted multiple age groups). The type of perforation in the shells is also consistent with use as beads, and not predator activity. Finally, remains of ochre were found inside the beads, suggesting they might have been painted, as other known bead samples.

In other words, the authors inferred intelligent agency because they were able to make specific hypotheses about how the perforated shells may have been generated, ruled out the hypotheses that indicated non-human activities, and found empirical confirmation for the hypotheses that pointed to design. Sounds easy, uh? It should be.