Chelicerate ancestry

pycno_anomaloPZ Myers on Pharyngula has a nice post about the group of invertebrates known as chelicerates: “Were sea spiders related to anomalocaris?”

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Quotes from Sarah Palin

I guess it takes a woman to make Dan Quayle look smart:

  • As Putin rears his head and comes into the air space of the United States of America, where– where do they go? It’s Alaska. It’s just right over the border.” –Sarah Palin, explaining why Alaska’s proximity to Russia gives her foreign policy experience, interview with CBS’s Katie Couric, Sept. 24, 2008 (Watch video clip)
  • “We believe that the best of America is not all in Washington, D.C. … We believe that the best of America is in these small towns that we get to visit, and in these wonderful little pockets of what I call the real America, being here with all of you hard working very patriotic, um, very, um, pro-America areas of this great nation.” –Sarah Palin, speaking at a fundraiser in Greensoboro, N.C., Oct. 16, 2008
  • “Ohh, good, thank you, yes.” –Sarah Palin, after a notorious Canadian prank caller complimented her on the documentary about her life, Hustler’s “Nailin Paylin,” Nov. 1, 2008
  • “Well, let’s see. There’s ― of course in the great history of America there have been rulings that there’s never going to be absolute consensus by every American, and there are those issues, again, like Roe v. Wade, where I believe are best held on a state level and addressed there. So, you know, going through the history of America, there would be others but ―” –Sarah Palin, unable to name a Supreme Court decision she disagreed with other than Roe vs. Wade, interview with Katie Couric, CBS News, Oct. 1, 2008 (Watch video clip)
  • “All of ’em, any of ’em that have been in front of me over all these years.” –Sarah Palin, unable to name a single newspaper or magazine she reads, interview with Katie Couric, CBS News, Oct. 1, 2008

Random selection?

We hear a lot from evolution skeptics and ordinary people who’ve been confused by them about, “how could all that happen by chance? Isn’t that just random selection? But it’s not. It’s random variation, then non-random selection.

Variation is random but selection depends on the conditions – from both the external environment and competition from fellow organisms.

Think of a sieve. Suppose you have a mixture of dry sand with dried peas and you want to eat the peas without sand. You can pick out the individual peas, which is slow and effortful. Or you can dump the whole lot into a colander and shake it. The motions of the peas and sand grains are effectively random. A grain of sand is able to go through a small hole and is less likely to hit another grain of sand and be bounced back up. You can’t predict which sand grain will strike the sieve where or whether it will strike a hole or a solid part. But after a minute, the sand has fallen through and the peas remain.

The motions of the peas and sand are random variation; the colander is the environment.

I do this to separate bite-sized bits from chaff when I get to the bottom of a box of cereal or to get rid of excess salt on salted nuts. If all the small pieces in a box of mixed snacks have sunk to the bottom, I turn the box over and shake it to re-distribute them. It’s a random process: but on average, the small pieces ar more likely to fall through a gap.

It would be instructive for domestic scenes in fiction to include an example like this.

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