fossils
pharyngula | October 27, 2008The Mesozoic was inhabited by some strange-looking critters, and here's another example: a Jurassic dinosaur called Epidexipteryx, which has spiky teeth, big claws, fluffy feathers all over its body, and four long decorative feathers coming off a stumpy tail. It resembles a particularly ugly bird with a nasty bite, but it couldn't fly — none of the feathers covering its forelimbs are pennaceous, but are more like an insulating fur. Or, alternatively, its feathers were all about display, a possibility suggested by the odd long feathers of the tail. Here are the bones; as you can see, the…
grrlscientist | October 17, 2008tags: Tiktaalik rosea, sarcopterygian, fishibian, fishapods, transitional fossil, evolution, vertebrate terrestriality, vertebrate evolution
A new study on the internal anatomy of the skull of the extraordinary fish, Tiktaalik roseae, which lived 375 million years ago, provides more evidence of how vertebrate life transitioned from water to land. The head showed changes from more primitive fish that helped adapt to the new feeding and breathing conditions presented by a terrestrial environment, scientists said.
Image: Ted Daeschler, Academy of Natural Sciences [larger view].
A paper was…
pharyngula | October 13, 2008
Here's a very strange fossil from the Chengjiang Lagerstätte, an early Cambrian fossil bed from 525 million years ago. It's a collection of Waptia-like arthropods, nothing unusual there; these are ancient creatures that look rather like headless shrimp. What's weird about it is the way the individuals are locked together in a daisy chain, with the telson (tail piece) of each individual stuck into the carapace of the animal behind. It's not just a fluke, either — they have 22 fossil chains, and just one animal all by its lonesome.
(Click for larger image)Waptia-like arthropod, Lower Cambrian…
grrlscientist | October 3, 2008tags: mammoth tooth, fossils, Hurricane Ike, Jim Westgate, Dorothy Sisk, paleontology
Paleontologist Jim Westgate, a research associate with the Vertebrate Paleontology Laboratory at the University of Texas Memorial Museum, shows off a newly discovered fossil tooth of a mammoth that he found in Caplen, Texas, in the debris from Hurricane Ike. Westgate believes the fossil discovered in the Ike-damaged debris is from a Columbian mammoth.
Image: Brian Sattler, Lamar University.
Hurricanes are very destructive, make no mistake about that. But imagine the surprise when Lamar University…
greengabbro | August 12, 2008The Scibling meetup weekend included free passes to see the ponies at the American Museum of Natural History. OMG PONIES... but I found the exhibit depressing, for the following reason:
I don't understand why more organizations don't give out press kits to bloggers. We make such good use of the material.
Anyway, the horse exhibit was nice, as far as exhibits about squishy living things go, but I ran off to see the rocks as quickly as possible. I wish I'd had time to do more than a quick jog through the earth science exhibits; there are ultra old-fashioned displays asserting that geologic…
pharyngula | July 30, 2008
This story is in the news again, so I've reposted my description of the paper from 3½ years ago. This is an account of the discovery of soft organic tissue within a fossilized dinosaur bone; the thought at the time was that this could actually be preserved scraps of Tyrannosaurus flesh. There is now a good alternative explanation: this is an example of bacterial contamination producing a biofilm that has the appearance of animal connective tissue.
Read GrrlScientist's explanation and Greg Laden's commentary and Tara Smith's summary of the recent PLoS paper that tests the idea that it is a…
grrlscientist | July 30, 2008tags: researchblogging.org, dinosaurian soft tissue, fossils, bacterial biofilms, paleontology, endocasts, formerly pyritic framboids, collagen
Figure 1. EDS spectrum of framboid. EDS spectrum of framboid showing an iron-oxygen signature. Pt is from coating for SEM. Area in red box was scanned for elements. [larger view].
DOI: 10.1371/journal.pone.0002808.
Some of you might remember a paper published in Science that rocked the paleontological world by revealing that a broken thigh bone from Tyrannosaurus rex contained soft tissue. When this soft tissue was analyzed, it was identified as…
grrlscientist | July 24, 2008tags: dinosaurs, Tarbosaurus bataar, paleontology, fossils, Tyrannosaurs rex
The newly unveiled fossil skeleton of the juvenile Tarbosaurus bataar in its protective jacket.
Discovered in 2006, a near-perfect complete skeleton of a juvenile Tarbosaurus find was made available for public viewing for the first time today by the Hayashibara Museum of Natural Science in Okayama, western Japan. This fossil was originally unearthed from a chunk of sandstone in the Gobi Desert of Mongolia by a team of Mongolian and Japanese researchers. The fossil of the young dinosaur is roughly 70 million years…
pharyngula | July 10, 2008Guess who's next in line to get a certain famous fossil? The Pacific Science Center will be exhibiting Lucy between October and March. Even if I can't arrange it, I expect you lucky Pacific Northwest residents to all make the pilgrimage.
grrlscientist | July 10, 2008tags: researchblogging.org, melanosomes, plumage color, feather color, fossil preservation, birds, dinosaur, Jakob Vinther
Male Red-bellied woodpecker, Melanerpes carolinus.
Image: Ken Thomas (Wikipedia) [larger view].
When looking at paintings and reconstructions of fossil birds and dinosaurs, people often ask "how do you know what color they were?" Well, we didn't. However, a new paper was just published in Biology Letters that explores the possibility of deciphering the actual color of fossilized plumage and makes a startling discovery: scientists can identify at least some of the…
grrlscientist | July 9, 2008tags: researchblogging.org, evolution, flatfish, Amphistium, Heteronectes, transitional fossils, missing link, Matt Friedman
During the development of extant flatfishes, such as this plaice, Pleuronectes platessa, one eye has migrated round the head to lie on the same side as the other. So these fishes have an 'eyed' (up) side and a 'blind' (down) side suitable for their bottom-dwelling lifestyle.
Image: KÃ¥re Telnes.
Flounder, turbot, sole, halibut and plaice (pictured above) are more than just a tasty slab of flesh on your plate. They are flatfishes that spend their adult life lying…
pharyngula | June 27, 2008
The paleontologists are going too far. This is getting ridiculous. They keep digging up these collections of bones that illuminate tetrapod origins, and they keep making finer and finer distinctions. On one earlier side we have a bunch of tetrapod-like fish — Tiktaalik and Panderichthys, for instance — and on the later side we have fish-like tetrapods, such as Acanthostega and Ichthyostega. Now they're talking about shades of fishiness or tetrapodiness within those groups! You'd almost think they were documenting a pattern of gradual evolutionary change.
The latest addition is a description…
pharyngula | June 2, 2008Sometimes, the politics of science can get ugly, and they don't get much uglier than this ghastly mess going on among paleontologists. I've read a couple of accounts of this story so far, and it sounds to this outsider like a few senior scientists riding roughshod over their junior colleagues and students and appropriating as their own the interpretations and details of others' explanations. There seem to be shenanigans all over the place, and it seems to be in the interests of all parties involved to resolve the issues.
The sensible thing to do would be to have an impartial review of both…
pharyngula | May 29, 2008
It's not often that something as delicate as details of the reproductive tract get preserved, but here's a phenomenal fossil of a Devonian placoderm containing the fragile bones of an embryo inside, along with the tracery of an umbilical cord and yolk sac.
(Click for larger image)
This is cool: it says that true viviparity, something more than just retention of an egg internally, but also the formation of specialized maternal/embryonic structures, is at least 380 million years old. Hooray for motherhood!
Here's a reconstruction of what the animal would have looked like in life, as it is…
pharyngula | May 25, 2008
It's another transitional form, this time an amphibian from the Permian that shares characteristics of both frogs and salamanders — in life, it would have looked like a short-tailed, wide-headed salamander with frog-like ears, which is why it's being called a "frogamander".
Complete specimen in ventral view, photograph (left) and interpretive outline drawing (right). Abbreviations: bc, basale commune; cl, cleithrum; cv, clavicle; dm, digital elements of the manus; dt3, distal tarsal 3; fe, femur; h, humerus; ic, intercentrum; il, ilium; is, ischium; op, olecranon process of ulna; pc,…
grrlscientist | May 18, 2008tags: researchblogging.org, Aves, Psittaciformes, Pseudasturidae, parrots, Palaeogene, Eocene, Denmark
An artist's impression of the parrot-like bird, Mopsitta tanta, dating back 55 million years. The fossils indicate that parrots once flew wild over what is now Norway and Denmark.
Image: David Waterhouse [larger view].
A team of researchers, including a former postdoctoral colleague of mine, recently described fossils from two Lower Eocene parrot-like birds that were discovered in Denmark. The analysis of the fossils reveals that one of the ancient parrots, named Mopsitta tanta, is the…
grrlscientist | April 25, 2008tags: researchblogging.org, evolution, dinosaurs, birds, Tyrannosaurus rex, ornithology, paleontology
The Tyrannosaurus rex femur from which researcher Mary Higby Schweitzer of North Carolina State University recovered soft tissue.
Image: Science.
It wasn't too long ago that paleontologists thought that fossilization was a process where all biological material was replaced with inert stone. However, in 2005, Mary Higby Schweitzer of North Carolina State University rocked the paleontological world when she recovered a still-elastic blood vessel from inside a fractured thigh bone fossil of…
pharyngula | April 10, 2008Check it out: it's yet another transitional form, a 92 million year old snake with two hindlimbs. Cool! Just last week I was told that none of these things exist.
awild | April 1, 2008
If you watch this video about a new technology for visualizing insect fossils hidden in opaque amber, pay special attention around 0:36-0:44. There's a brief 3D image of what is clearly a well-preserved sphecomyrmine ant. The clip is excerpted from a detailed demonstration here, showing the insect in all its glory (warning: 57MB!). It's among the most detailed glimpses of a Sphecomyrmine yet.
Why is this ant interesting? Sphecomyrminae is in many respects a classic piece of evidence for the wasp ancestry of ants. It is an extinct Cretaceous subfamily that shows a few characteristics of…
grrlscientist | February 23, 2008tags: Evolution: What The Fossils Say And Why it Matters, fossils, dinosaurs, creationism, Donald Prothero, book review
I was in love with dinosaurs when I was a kid, and I still am. It was my love for dinosaurs and fossils and especially my time spent learning the minutea of the evolutionary history of horses that quickly brought me into direct conflict with the church that I was being inculcated into when I was very young and innocent. Subsequently, I had to learn about evolution in small niblets on the sly. But I wish I had been able to read paleontologist Don Prothero's beautifully…