Palaeos reborn!

First I reported that Palaeos was lost, and then that it might be found, but now it looks like we can safely say it is being reborn. The old version of Palaeos has been at least partially restored, but the really important news is that a Palaeos wiki has been set up and people are working on reassembling old content and creating new information in a much more flexible format. If you’ve got some phylogenetic or palaeontological expertise, you might want to consider joining the Palaeos team and helping out with this big project.

3.3 million years old, 3 years old

Say hello to Selam, or DIK-1-1, a new and very well preserved member of the family discovered in Dikika, Ethiopia. She belongs to the species Australopithicus afarensis and is being called Lucy’s little sister.

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She was only a toddler when she died about 3.3 million years ago, and from the teeth the authors estimate that she was about 3 years old. Most of the skeleton is intact, but doesn’t seem to have yet been fully extracted from the matrix.

Some of the surprises: the hyoid bone is chimpanzee-like, and implies chimp-like vocalization abilities. She had a long way to go before she could have a conversation. The fingers are long and curved, and the scapula is more gorilla-like than ours; there is a suggestion of better arboreal ability than we have.

Alemseged Z, Spoor F, Kimbel WH, Bobe R, Geraads D, Reed D, Wynn JG (2006) A juvenile early hominin skeleton from Dikika, Ethiopia. Nature 443:296-301.

What works, what doesn’t: the futility of appeasing creationists

An old pal of mine, the splendiferously morphogenetical Don Kane, has brought to my attention a curious juxtaposition. It’s two articles from the old, old days, both published in Nature in 1981, both relevant to my current interests, but each reflecting different outcomes. One is on zebrafish, the other on creationism.

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Carnivalia, and an open thread

We just had one of these!

Well, just to flesh it out a little more with some random links, here are some photos. I was told the second one made someone think of me (warning: body modification!). And, jebus help me, for some reason I thought this photo was very sexy. Or appetizing. I don’t know, something in the midbrain flickered.

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Oh, and several of us sciencebloggers were interviewed for an article by Eva Amsen on “Who benefits from science blogging?” It doesn’t mention the benefit of people sending you pictures that tickle the cingulate.

Rhabdomeric and ciliary eyes

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We are all familiar with the idea that there are strikingly different kinds of eyes in animals: insects have compound eyes with multiple facets, while we vertebrates have simple lens eyes. It seems like a simple evolutionary distinction, with arthropods exhibiting one pattern and vertebrates another, but the story isn’t as clean and simple as all that. Protostomes exhibit a variety of different kinds of eyes, leading to the suggestion that eyes have evolved independently many times; in addition, eyes differ in more than just their apparent organization, and there are some significant differences at the molecular level between our photoreceptors and arthropod photoreceptors. It’s all very confusing.

There has been some recent press (see also this press release from the EMBL) about research on a particular animal model, the polychaete marine worm, Platynereis dumerilii, that is resolving the confusion. The short answer is that there are fundamentally two different kinds of eyes based on the biology of the cell types, and our common bilaterian ancestor had both—and the diversity arose in elaborations on those two types.

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