My friend Barry always used to say that the reason that “silly” positions are so named in cricket is because they didn’t want to call them “damn stupid”…anyone fielding so close to the batsman must be damn stupid to do so.
Apparently early humans evolved a protein to protect themselves from infection by a retrovirus that infects chimpanzees. In so doing, they left themselves more vulnerable to HIV infection. Apparently the human TRIM5α protein protects against the PtERV1 virus. In rhesus monkeys, TRIM5α protects against infection from HIV-1. But it looks like there is a trade off:
Unexpectedly, however, the researchers found that no version of TRIM5α from any primate could neutralize both PtERV1 and HIV—it was either one or the other, Emerman says. What that implies, he says, is “humans are susceptible to HIV today because of a response to something else we had in the past.”
Greg Laden calls this an example of “stoopid design“. I’m more inclined to think of it as malicious design. Working from a Beheian perspective, if new species must be intelligently designed, Behe’s intelligent designer must have observed early humans commit their TRIM5α to the job of protection from PtERV1 and decided to engineer HIV to exploit that weakness.