The Sacramento Bee has good pictures of the Lianga Bua, Indonesia, site where Homo floriesiensis remains have been found. As you will notice, they’re not just scraping the floor of a nice shallow cave with trowels.
Hat tip to James Kidder.
A common bleat from creationists is “Where are the millions of transitional fossils Darwin said there should be?” Martin Brazeau has an excellent post on taphonomy at The Lancelet reporting a paper in which folks let poor innocent critters rot in order to ascertain which anatomical features are likely to be preserved and which are likely to be lost before fossilization, and the implications for interpreting fossils of ‘soft’ tissues for phylogenetics. Comment there, please.
Hello from Kearney Nebraska, where I am lucky to be a speaker along with a great number of actually famous people at the University of Nebraska’s Evolution2009 conference. I am mostly offline at the moment, but I have been told that the Darwin Correspondence Project in Cambridge has just announced that I have won the prize for one of their competitions – finding the true source of a famous, but bogus, quote of Darwin. The quote goes as follows (there are many varieties):
It is not the strongest of the species that survives, nor the most intelligent that survives. It is the one that is most adaptable to change.
David Hone, a British paleontologist working in China who blogs at Archosaur Musings, has a fascinating post on tracking the reporting of a paper he recently published. Among other things, he was able to follow the ‘Chinese whispers’ or ‘telephone game’ transmission of the news stories by tracking errors that crept into the story as it was published here and picked up there:
Thus science stories can really pick up and spread this way, so although 24 hours after my press release I had only one mention in one paper, after 48 hours this was more than five and another 24 hours later this was more than twenty. One week later it’s up to about fifty and I am still getting new e-mails about this.
This spreading though is especially interesting as between the original press release(s), the paper itself and the blog post (and later interviews) I know which quotes and which information came from where and thus which errors or changes have come in at which stage and which media have picked them up from which other. It is noticeable therefore that one can track errors from report to report as they originate in one and then are copied to others (I tracked a spelling mistake of Tyrannosaurus as Tyrannosaurs across three generations of articles, and each time it appeared in basically the same sentence in the second paragraph of the report, each, theoretically written by a different journalist).
Shades of pseudogene phylogenies! Go and read it and enjoy it there, and comment there if you feel moved to do so to encourage him to keep ‘em coming.
I’m back from field work, and have finally gotten enough time to get my photos web-ready after returning from Batholiths Onland. (see Blogging Batholiths: Part 1 for a summary of the 1st 8 days of the adventure, and a description of the scientific goals of the project; the part 1 photo essay is here.)
The updated photo tour includes reactions to the activist who tried to sabotage the project, finally getting some data, splendid photos from team members, and more. Part 2 starts off with a hike up to the gorgeous falls in Hagensborg, BC, and can be found here.
Comments may be left here or there, but nowhere in between.
Update: a piece about the failed attempt to sabotage the project, “Eco-warrior trashes seismic experiment” by Rex Dalton, appears in the 23 July 2009 issue of Nature.
Update, Aug. 5th, 2009: Forest fires have come to the region. More below the fold.
I am currently in British Columbia, Canada, participating in the Batholiths Onland experiment.
Nominally, this large group effort involving over 50 scientists and grad students is for “a seismic refraction and wide-angle reflection survey across the Coast Mountains batholith of British Columbia, Canada.”
This rather terse description does not really do justice to the project, which has the purpose of discovering why continental mountain ranges are often made of granite instead of basalt.
Relevance to the Panda’s Thumb? (1) Real science involves real work; when is the last time you saw a creationist actually measure something, or use a shovel? (2) Real scientists think the earth is billions of years old. You just can’t scientifically reconcile these batholiths with a 10,000-year old earth without being more than a little schizophrenic.
The latest issue (July/August, 2009) of Discover Magazine had a handful of splendid articles, but what really caught my eye was a remarkably detailed image of a 100-million-year-old wasp that had been fossilized inside an opaque piece of amber (p. 39). I could not find the picture on the Discover website, but I easily tracked it to here, where you may see it along with a number of other images.
According to the Discover article, Paul Tafforeau and colleagues at the European Synchrotron Radiation Facility used a beam of x-rays to probe the interiors of bits of amber that are opaque to visible light. They found hundreds of fossilized beetles, ants, wasps, flies, and bits of plants, and made tomograms (or 3-dimensional reconstructions) of some of them. None of the trapped insects was bigger than a few millimeters, presumably because larger insects were not so easily trapped by the resin.
Discover notes that the team found more than 600 insects, none of which appears to be a modern species. It is not clear how many different species those insects represent, but Tafforeau says, “Each scan is a new discovery,” so I infer that they have discovered a great many new, ancient species - and that is among small insects only.
If you believe, with Lucretius and certain of our creationist colleagues, that species are not born but only die out, then all I can say is there must have been at one time one helluva lot of species.
I’ve been thinking about comets a lot lately, trying to image C/2009 G1, reading “The Hunt for Planet X”, wondering why Galileo was so wrong about them and recently reading a Young Earth creationist blog post on them. The latter referred to a very interesting pre-publication article. And I’d like to discuss this article, as this illuminates not only the origins of comets but also how science is done.
Image Credit ESO (click to embiggen).
The Gliese 581 system delivers again. Giese 581 is a red dwarf star 20.4 light years away that until recently boasted the lightest extrasolar planet ever found. At 5 Earth masses, Gliese 581c was not exactly a second Earth, but it and 7 Earth mass Gliese 581d captured the worlds imagination as they seemed to be in the habitable zone of their parent star, where liquid water can exist.
Now the smallest mass planet ever has been discovered around Gliese 581, a 1.9 mass planet Gliese 581e, presumably rocky, that screams around Gliese 581 in a little over three days. At a mere 0.03 Astronomical Units from its star, Gliese 581e is a Mercury-like world, baking in the close embrace of the Red Dwarf.
(The following is a slight adaptation of this essay. Readers may post questions and/or comments there as well as here.) As this series of essays has explained, the polyadenylation of messenger RNAs is a vital aspect of gene expression in eukaryotic cells (and a not-so-unimportant facet of RNA metabolism in other contexts). Polyadenylation is mediated by a sizeable complex that includes various RNA-binding proteins, nucleases, and other interesting activities. Genetic studies in yeast indicate that virtually every subunit of the core complex is essential - for viability and for pre-mRNA processing and polyadenylation in vitro and in vivo. (This review is freely available and serves as a good starting point for readers who wish to explore the subject further.) Biochemical and/or immunological depletion studies reveal a similar scenario in mammals, and a less-expansive set of studies suggests that a similar rule of thumb will apply in plants. The bottom line of all of this is that almost all of the subunits of the polyadenylation complex seem to be essential - remove one, and the complex cannot function. In the vernacular of a proponent of intelligent design, the polyadenylation complex would seem to be irreducibly complex.
It is in this context that the recently-completed genome of the parasitic organism Giardia lamblia enters the fray. Last year, the complete sequence of G. lamblia, some 12 million base pairs, was determined and analyzed. The authors of the study published in Science noted a number of interesting things - a preponderance of genes encoding protein kinases, evidence for substantial horizontal gene flow from bacteria and archaebacteria, and a streamlined core gene expression machinery (transcription and RNA processing). This streamlining is especially notable in the case of the polyadenylation machinery. Remarkably, of all the subunits in the yeast complex, genes for only three* can be found in G. lamblia (see the figure that follows this paragraph - adapted from Fig. 1 of Morrison et al.).
An interesting new paper is just out today in PLoS ONE. You recall the announcement a few years back that soft tissue that resembled organic tissue had been isolated from a Tyrannosaurus femur. This started off a huge controversy in the field (and beyond)–researchers disagreeing with each other whether the structures seen were indeed blood cells and vessels; creationists crowing about how this finding represented “proof” that the earth was indeed young and dinosaurs had existed just a few thousand years ago; and of course, talk of cloning and DNA analysis. On the side of “soft tissue = dino blood” were findings that reported identification of the iron-containing protein heme (potentially from the red blood cells) and morphology of cells and vessels similar to that seen in modern-day ostriches and emu. However, the new paper by Kaye et al. provides an alternative explanation: that the structures aren’t actual vessels and cells, but are instead iron-rich bacterial biofilms. Read the rest over at Aetiology…
The Rockefeller University presents a two day symposium on “From RNA to Humans”
With videos of all the lectures
Feeding and Gloating for More: The Challenge of the New Creationism Jerry A. Coyne, The University of Chicago
We keep hearing from Intelligent Design Creationists that the fossil record is lacking in transitional fossils. To support their claims, they consistently quote mine statement by Gould and others while ignoring the actual data.
Thanks to modern technology, Youtube presents Transitional Fossils I and II by DonExodus2
From Cassini Raw Images, specifically here.
I missed this one a week or two ago. Simon Conway Morris and his colleague Jean-Bernard Caron published a paper in Science on a new Cambrian fossil called Orthrozanclus. The cool thing about the fossil is that it combines features from two other fossils that Conway Morris previously implicated as transitional stem groups between the modern crown groups (“phyla”) of mollusks, annelids, and brachiopods: Wiwaxia and Halkeria. Of course, according to Discovery Institute propaganda, transitional fossils like this don’t exist.
Here is a news summary. See also the Orthrozanclus post from PZ Myers, his post last year on another stem group mollusk-ish critter, Odontogriphus.
Titan Has Liquid Lakes, Scientists Report in Nature Jan. 3, 2007 (Source: JPL)
Liquid Lakes on Titan The existence of oceans or lakes of liquid methane on Saturn’s moon Titan was predicted more than 20 years ago. But with a dense haze preventing a closer look it has not been possible to confirm their presence. Until the Cassini flyby of July 22, 2006, that is.
Scientists report definitive evidence of the presence of lakes filled with liquid methane on Saturn’s moon Titan in this week’s journal Nature cover story.
Radar imaging data from a July 22, 2006, flyby provide convincing evidence for large bodies of liquid on Titan today. A new false-color radar view gives a taste of what Cassini saw. Some highlights of the article follow below.
It is well known that The Panda’s Thumb is not just an evolution blog, it is also occasionally a Cassini-Huygens fanclub blog. We live-blogged the Huygens landing, and gushed over the discovery of stream channels (although annoyingly the methane oceans have not yet appeared, there clearly is some kind of methalogical cycle going on).
Someone has finally done the obvious thing and put together all of the Huygens images into a continuous animation. See the one with narration and the one with boops and beeps indicating various onboard processes. The fisheye camera perspective is kind of weird but we get a much better picture of what the surface topography looked like up close than we did from just the isolated snapshots.
It all just makes me wish they’d put a balloon and one of them plutonium-fueled Radioisotope Thermoelectric Generators on Huygens so that it could float around for a few months at 10 k elevation and give us some more details of what is down there.
While I’m demanding things from NASA, here are my other requests for the Cassini mission if it goes into “extra innings” like other recent NASA missions have: (1) get some more images of the Giant Equatorial Ridge on Iapetus, (2) full radar map of Titan’s surface, and then (3) a suicide mission to get a really super-up-close view of Saturn’s rings. I want to see the individual particles, darn it! A friend tells me there is no way to slow down the Cassini craft enough to get both slow enough and close enough to image 1-meter ice boulders, but I don’t buy it. There has got to be a way!
