The Knowledge of the Glory

The appendix is still erroneously reported in some textbooks as proof of evolution. This traces back to Darwin, who called it a vestigal organ—the remnant of a previously-existing organ which evolution had outdated. Darwin thought it was all that was left of a larger bowel called a cecum.

Evidence has mounted against this evolutionary proposal. Studies since Darwin’s day show that 70% of rodents and mammals have groups with appendices—including several which have the larger cecum bowel, which raises the question, what is their appendix a vestige of? Furthermore, appendices appear in species which are unrelated by evolution. How and why did the same organ appear in unrelated species? Did evolution strike in the same way twice? What are the odds of that?

Actually the appendix is now thought to serve a unique and necessary function. The bowel needs certain bacteria to function properly. If these are wiped out, they must be repopulated for the health of the host. This led Maryland researchers to propose that the appendix serves as a “safe haven” for such bacteria and allows the re-population of these benign symbiotic forms in their hosts. Thus the appendix turns out to be beneficial and there is more than a hint of good design.

But what about appendicitis? Again this turns out to be a function of changes in human society, which have set it up for inflammation, rather than faulty design in the organ.

This entry was posted on Sunday, August 23rd, 2009 at 11:17 am and is filed under Biology. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.