Scientists, neuter yourselves!

Chad reports a not-so-subtle message from a science conference:

The annoying thing was the peripheral message– she took pains to state several times that both Democrats and Republicans in Congress support science, in a tone that basically came across as chiding us for thinking otherwise. That was annoying by itself, but at the very end of the talk, she specifically warned against taking partisan positions, citing the letter supporting John Kerry that was signed by a couple dozen Nobel laureates as something that made it harder to keep science funding. She said that after that, when she met with administration officials about budget matters, she could see them thinking “Damn scientists…”

When the government says or does something scientifically stupid, it is our solemn duty to go along with it.

Jellyfish lack true Hox genes!

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I’m going to briefly summarize an interesting new article on cnidarian Hox genes…unfortunately, it requires a bit of background to put it in context, so bear with me for a moment.

First you need to understand what Hox genes are. They are transcription factors that use a particular DNA binding motif (called a homeobox), and they are found in clusters and expressed colinearly. What that means is that you find the Hox genes that are essential for specifying positional information along the length of the body in a group on a chromosome, and they are organized in order on the chromosome in the same order that they are turned on from front to back along the body axis. Hox genes are not the only genes that are important in this process, of course; animals also use another class of regulatory genes, the Wnt genes, to regulate development, for instance.

A gene can only be called a Hox gene sensu stricto if it has a homeobox sequence, is homologous to other known Hox genes, and is organized in a colinear cluster. If such a gene is not in a cluster, it is demoted and called simply a Hox-like gene.

Hox genes originated early in animal evolution. Genes containing a homeobox are older still, and are found in plants and animals, but the particular genes of the Hox system are unique to multicellular animals, and that key organization arrangement of the set of Hox genes in a cluster is more unique still. The question is exactly when the clusters arose, shortly after or sometime before the diversification of animals.

If you take a look at animal phylogeny, an important group are the diploblastic phyla, the cnidarians and ctenophores. They branched off early from the metazoan lineage, and they possess some sophisticated patterns of differentiation along the body axis. We know they have homeobox containing genes that are related to the ones used in patterning the bodies of us vertebrates, but are they organized in the same way? Did the cnidaria have Hox clusters, suggesting that the clustered Hox genes were a very early event in evolution, or do they lack them and therefore evolved an independent set of mechanisms for specifying positional information along the body axis?

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A little more on the amorality of religion

August Berkshire, the other atheist in Minnesota (well, there are a few others), has a fine piece in the Strib on that frothy mix of morality and religion—Rabbi Shafran ought to read it.

The Bible is like a Rorschach inkblot test: you can see just about anything you want in it. That is why Christians themselves cannot agree on such things as masturbation, premarital sex, contraception, abortion, divorce, homosexuality, stem cell research, euthanasia and the death penalty. The Bible or religion as a moral guide? With all this disagreement, how is that possible?

Rabbi Avi Shafran

There is no more reverent way to wake to a fine Sunday morning than to discover another religious zealot punching himself in the face. Repeatedly. The Rabbi Avi Shafran is waxing indignant in a syndicated article that is popping up all over the place, in which he tries to denounce Zizek’s most excellent article on the virtues of atheism. The best he can do, though, is whimper at length that atheists are just plain bad people—it’s an argument to appeal to bigots who already have a prejudiced view of those who don’t share their religion, but it’s not very persuasive to people who can think.

It is fun to shred, though.

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