Wednesday, May 15, 2013

Malaria and fossil ear bones

A few interesting articles came out recently, and I thought you might like hearing about them.

First, in the May 10 Science comes a report of a new "breed" of mosquito that is resistant to infection by the malaria parasite Plasmodium falciparum.  Malaria is normally transmitted by the bites of malaria-infected mosquitoes, and one obvious means of combating malaria is to target the mosquitoes.  Typically, this is done with insecticides that kill the mosquitoes, but this new report indicates an intriguing new method of control: infecting mosquitoes with Wolbachia.  Wolbachia is a bacterial symbiont of some insects, and Bian et al. report that they've developed a bacterial strain that will form a stable - and heritable - relationship with one of the mosquitoes that transmits malaria.  Mosquitoes carrying the Wolbachia symbionts are resistant to malaria.  Think about that: A bad relationship (malaria-mosquito) is prevented by establishing a beneficial one (Wolbachia-mosquito).  This reminds me of the kind of things Joe Francis has been telling me: All of creation was built to be in relationship, and pathology is merely the fault of bad relationships instigated by the Fall.  If he's right, it should be possible to repair these pathologies by creating or restoring good relationships.  And so mosquitoes living with good bacteria help prevent malaria transmission.  Great stuff!

Bian et al. 2013. Wolbachia invades Anopheles stephensi populations and induces refractoriness to Plasmodium infection.  Science 340:748-751.

Second, the latest online publication from PNAS describes complete ear ossicles from Paranthropus and Australopithecus.  According to many creationists, these two genera are non-human hominids, erect apes that are not part of human evolution, even though paleoanthropologists say otherwise.  This paper caught my eye because creationists have characterized both of these genera as "mosaics," with some characteristics resembling humans and others resembling apes.  So too, it seems, with the ear ossicles.  Do you remember the hammer, anvil, and stirrup (AKA malleus, incus, and stapes) from your high school biology lessons?  They're the smallest bones in the human body, and they help transmit sound from your eardrum to your brain.  It seems in both Paranthropus and Australopithecus, the hammer (malleus) is similar to the human malleus, but the other two bones (incus and stapes) are more similar to those of living great apes.  Once again, mosaics.

Quam et al. 2013. Early hominin auditory ossicles from South Africa. PNAS doi:10.1073/pnas.1303375110.

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