The Loom

Talking Soul In DC

I’m en route to Washington DC to talk tonight about Soul Made Flesh. If you’re in the District, please come to Reiter’s Bookstore at 2021 K Street NW at 6:30. On my web site I’m posting all my talks and radio interviews as they get confirmed.

In lieu of a blog of my own, let me point to a couple interesting items.

–At Quark Soup, David Appell gets righteously indignant about a new paper that predicts a major wave of extinction due to global warming. Actually, the paper could turn out to be a conservative underestimate (not to be confused with certain politically conservative underestimates of these sorts of things). Habitat loss, biological invasions, nitrogen pollution, increases in diseases, overfishing, and other impacts on endangered species may well work together synergistically, so that the whole of their damage is more than the sum of their parts.

–At the Intersection, Chris Mooney muses on genetically engineering mosquitoes to fight malaria. He’s right to ask whether malaria-proof mosquitoes can compete in the evolutionary arena with wild mosquitoes. In fact, I just know I read some research published recently that indicated the bugs probably get knocked out. Evolution often works as a tradeoff between fighting off parasites and using that energy for other things, like moving or eating. Unfortunately, I don’t have the time in transit to find it. In any case, all grand dreams of genetic modification need to take natural selection into account

Comments

  1. #1 mary freeman
    January 8, 2004

    I live in the land of the black fly, Maine, where they bite humans. But I once met a man (PhD) who told me in the midwest they have a species of black flies which only bites deer not people. I have thought for years since then that someday scientists would figure out what keeps those black flies in the midwest from biting people and then figure a way to bioengineer all mosquitoes, black flies, etc. (dedesease and non-desease-bearing pests) to do the same. (In fact I put it in my (futuristic) epic poem as a given!) How close are we (as a species) to doing that sort of thing, do you think?

  2. #2 charles
    January 8, 2004

    Regarding the predicted extinctions:

    a) Do we have data regarding extinctions from the warming of the last 100, 50, 30 years?

    b) I understand the mentioned paper refers to the IPCC scenarios. If we use the Hansen (http://naturalscience.com/ns/articles/01-16/ns_jeh6.html ) scenario of 2oc over the next 100years, what will be the expected result? Does it correlate to a)?

  3. #3 Karl Hallowell
    January 10, 2004

    I think we should plan on extinctions occuring and devise long term plans for recovering species from extinction. For example, a small nuclear war or other global catastrophe could extinguish all large wild mammals on Earth through the collapse of social order that might control the consumption of these species or of their habitat. I consider such an event fairly likely since the human race IMHO isn’t taking percautions (hoarding food, keeping small breeding populations in isolation, etc) in case of widespread disaster.

    As far as part B goes, Malaria offers a pretty significant advantage to Malaria-bearing mosquitoes. I think that a program to raise competitors would have to come up with ways to evolutionarily increase the success of their versions and diminish the success of the Malaria breeds. One such point is the adult stage which I suspect is very high mortality. After all, the females need warm blood. I’d think that’s not easy. Imagine that your competitors get free food when they become adults and you might be able over a decade or two to flood out the Malaria bearing mosquitoes. Add a bunch of sterilized male mosquitoes and that might do the trick?

  4. #4 Oliver Morton
    January 14, 2004

    On the mosquitoes, I’m afraid I don’t remember the reference either, but I too remember that there has been some work showing lower fitness. More generally it seems to me that trying to change mosquito susceptibility or transmissiveness is always going to be a lot more complex and possibly more risky than just trying to wipe them out.

    Austin Burt at Imperial College has thought up a way to use homing endonuclease genes, which are non medelian segregation distorters (which means that they get into almost all offspring rather than only half) to spread lethal recessives through an insect population. If it worked more or less as advertised, this could be used to wipe out vector species for malaria in the wild one by one. Without vectors the disease dies out. Then, should you wish to do so, you can re-release wild type vectors (without malarial parsites) back into the world.

    Wiping out the vectors so as to trap and kill the parasites, then re-releasing the vectors, seems to me less ecologically invasive than the long term uncontrolled release of modified vectors. I wrote this up for New Scientist (subscription required, alas) last year, and Olivia Judson (who’d first mentioned Austin to me — he’s a friend of hers) championed it on the op ed page of the New York Times some time in the fall. It would fit into the seventh of the Gates Foundation’s grand challenges for global health.

  5. #5 inkjet cartridges
    September 5, 2004

    7463 Thanks so much for all the help to buy ink cartridges