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Category Archive: Fossils

Jul 11 2012

Swimming in the Cambrian

musclefibers

If you ever get a chance, spend some time looking at fish muscles in a microscope. Larval zebrafish are perfect; they’re transparent and you can trace all the fibers, so you can see everything. The body musculature of fish is most elegantly organized into repeating blocks of muscle along the length of the animal, each …

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Apr 25 2012

Modular gene networks as agents of evolutionary novelty

A while back, I told you all about this small piece of the biochemistry of the fly eye — the pathways that make the brown and red pigments that color the eye. I left it with a question: if even my abbreviated summary revealed considerable complexity, how could this pathway evolve? Changing anything produces a …

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Dec 29 2011

Protists, not animals

tianzhushania

I’ve written about the spectacular phospatized embryos of the Doushantuo formation before. It’s a collection of exceptionally well preserved small multicellular organisms, so well preserved that we can even look at cellular organelles. And they’re pre-Cambrian, as much as 630 million years old. They’ve been interpreted as fossilized embryos for which we have no known …

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Dec 20 2011

The eyes of Anomalocaris

anomalocaris_eyes

Look with your puny camera eyes! Some new specimens of Anomalocaris, the spectacular Cambrian predator, have been discovered in South Australia. These fossils exhibit well-preserved eyes, allowing us to see that the bulbous stalked balls on their heads were actually fairly typical compound eyes, like those of modern insects. Anomalocaris eyes from the Emu Bay …

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Dec 15 2011

Creationist abuse of cuttlefish chitin

A few weeks ago, PLoS One published a paper on the observation of preserved chitin in 34 million year old cuttlebones. Now the Institute for Creation Research has twisted the science to support their belief that the earth is less than ten thousand years old. It was all so predictable. It’s a game they play, …

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Oct 10 2011

Traces of a Triassic Kraken?

shonisaur

At first I thought this discovery was really cool, because I love the idea of ancient giant cephalopods creating art and us finding the works now. But then, reality sinks in: that’s a genuinely, flamboyantly extravagant claim, and the evidence better be really, really solid. And it’s not. It’s actually rather pathetic. It consists of …

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Sep 16 2011

Showoff

ammonite

Emily Baldry is six years old. Emily has a little plastic shovel. Emily dug up a 160 million year old cephalopod. I’m 54, I have a little plastic spoon, and I’m eyeing the backyard. There used to be cephalopods swimming around in this neighborhood…of course, there were also some annoying glaciers that scoured the landscape. …

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Sep 03 2011

Not like a worm?

Ann Coulter is back to whining about evolution again, and this week she focuses on fossils. It’s boring predictable stuff: there are no transitional fossils, she says. We also ought to find a colossal number of transitional organisms in the fossil record – for example, a squirrel on its way to becoming a bat, or …

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Aug 28 2011

Bacterial fossil doubts resolved

I raised a few questions about those 3.4 billion year old bacterial fossils, primarily that I was bugged by the large size and that they cited a discredited source to say that they were in the appropriate range of diameters for bacteria. Now my questions have been answered by Chris Nedin, and I’m satisfied. In …

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Aug 24 2011

A questions about those ancient bacterial fossils…

Both Jerry Coyne and Larry Moran have good write-ups on the recent discovery of what are purportedly the oldest fossil cells, at 3.4 billion years old. I just have to add one little comment: a small, niggling doubt and something that bugs me about them. All the smart guys are impressed with this paper, but …

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