paleontology
laelaps | January 27, 2008
An early reconstruction of Megalosaurus, as alluded to by William Buckland in the text below. (Image source)
Yesterday a 1st edition copy of Francis Buckland's Curiosities of Natural History (1857) appeared in my mailbox, and it has proven to be a most delightful book. If you can find this book I would highly suggest you take the time to read it; it is wonderfully written and entertaining (although, as would be expected, there are some inaccuracies here and there). Francis Buckland was the son of famed geologist William Buckland, and throughout the book Francis pays homage to his father in…
laelaps | January 27, 2008Will has the latest edition of The Boneyard up at The Dragon's Tales. Check out some of the best paleo-posts from the last two weeks and keep your eyes open for new ones; the carnival will be over at Greg's place on February 9th.
[As an aside, yesterday was also the birthday of Roy Chapman Andrews. Michael put up a concise little bio in honor of the occasion.]
gregladen | January 25, 2008
Did humans wipe out the Pleistocene megafauna? This is a question that can be asked separately for each area of the world colonized by Homo sapiens. It is also a question that engenders sometimes heated debate. A new paper coming out in the Journal of Human Evolution concludes that many Pleistocene megafauna managed to go extinct by themselves, but that humans were not entirely uninvolved.
The paper by Pushkina and Raia ("Human influence on distribution and extinctions of the late Pleistocene Eurasian megafauna") examines sources in the literature and a number of databases for Eurasian…
laelaps | January 25, 2008I may or may not be able to get to all this stuff in detail today, but here's a smattering of some paleo news to start your day with;
Paleontologists have known for a number of years that the Chicxulub crater in the Yucatan peninsula is likely the "smoking gun" for the end-Cretaceous meteor impact, but new research suggests that the bolide struck the earth in water deeper than originally thought. This would modify ecological effects in the wake of the impact, and it was good to read that a variety of short-term and long-term effects of the event were considered in the new research;
[Sean]…
gregladen | January 23, 2008The end-Permian mass extinction event was the big daddy of all the known mass extinction events. Life on the planet Earth was almost entirely wiped out. A new paper explores the post-extinction recovery of ecological systems.
Post extinction dynamics can be understood in relation to several dimensions: Taxonomy (the range and structure of different taxonomic groups); ecology (the interrelationship between the new species and the niches available, as well as the structure and distribution of those niches); and morphology (the overall morphospace filled by the new taxa). The present study…
grrlscientist | January 17, 2008tags: researchblogging.org, Josephoartigasia monesi, Giant South American rodent, fossils, megamammals, Dinomyidae
The head of the newly-found Josephoartigasia monesi (A), in comparison to a South American rodent known as a pakarana, Dinomys branickii (B).
Image: G. Lecuona [larger size].
As a resident of NYC, you often hear stories of enormous rats that are aggressive enough to fight an alleycat -- and win. Even though I watch the rats run around in the subways and am impressed by their audacity, I've never seen any rats that had reached a particularly impressive size, although I have…
gregladen | January 17, 2008Things are just not like what they used to be. You know this. You know that the Age of Dinosaurs, for instance, was full of dinosaurs and stuff, and before transitional fossil forms crawled out of the sea to colonize the land, all animals were aquatic, etc. But did you know that from a purely modern perspective, the Miocene was the most important geological period?
First, lets get one thing straight. We are not in the so-called "Holocene." The so-called "Holocene" is a totally bogus geological period. Saying "Hey, we're in the Holocene, not the Pleistocene ... the Pleistocene is over…
laelaps | January 17, 2008Yesterday I received my review copy of Grave Secrets of Dinosaurs: Soft Tissues and Hard Science by Phillip Manning (supposedly all about the hadrosaur mummy "Dakota"), and while I usually try to keep quiet about my thoughts on a book until I've finished it I just can't keep my trap shut this time. I will write a full review very soon (I'm more than halfway through the book), but I am extremely disappointed with this piece. The book contains no index, no bibliography/references, and there are virtually no pictures of the dinosaur the book is supposed to focus on (save for a scan of a segment…
laelaps | January 17, 2008Darren has announced that there will soon be a conference over in the UK called "Dinosaurs - A Historical Perspective," and it sounds like it'll be one of the most fantastic meetings to take place in paleontology this year. I can't go (have debt, won't travel), but if you can I would highly encourage you to do so, especially if you've got something you can submit for the conference. The deadline for abstracts is January 28th, though, so you'll need to get working if you've got something to submit, but it sounds like just the sort of thing I'd love to contribute to if I had the chance (see…
laelaps | January 16, 2008
A capybara (Hydrochoerus hydrochaeris) at the Cape May Zoo. Josephoartigasia dwarfs this animal, the largest of the living rodents.
One of the most interesting evolutionary patterns is an increase in the disparity of sizes in a group, small representatives persisting and changing even as some lineages get larger (I'll address this issue a bit more in a separate piece of Cope's Rule, if such a thing even truly exists). A new Pleistocene fossil rodent from Uruguay called Josephoartigasia monesi further elucidates this trend, being the largest fossil rodent yet discovered with an estimated…
laelaps | January 15, 2008You can see it over at One Good Move. Shubin's book, Your Inner Fish hit bookstores today.
laelaps | January 15, 2008Fossils are fragile, rare things; despite their abundance in some areas, we're pretty fortunate to have the remains of animals that lived and died in the distant past. One of the problems in modern paleontology (and in nearly any scientific discipline that requires fieldwork), though, is the bureaucratic red tape that can slow and even halt excavations of important finds. According to the Los Angeles Times, such is the problem with a Miocene baleen whale skull discovered by amateur paleontologist Daryll Hansen in Orange County, CA. The problem is that the remains (primarily what appears to be…
laelaps | January 15, 2008
Plumulites bengtsoni. From Vinther, J.; Van Roy, P.; Briggs, D. (2008) "Machaeridians are Palaeozoic armoured annelids." Nature, Vol 451, pp. 185-188 doi:10.1038/nature06474
Last week I briefly mentioned a new paper in Nature about an "armored worm" called Plumulites bengtsoni, and I've finally gotten a chance to read a bit more about this strange Ordovician creature. Previously, fossils determined to belong to a group called the machaeridians were found in great abundance, but like conodont teeth before the discovery of a more complete organism, no one was sure what sort of animal the…
laelaps | January 14, 2008
The trailer for the film The Land That Time Forgot.
My first impression of what a dinosaur was conjured up images of creatures impossibly big and toothy, real-life monsters with names that sounded like they could very well have been out of mythology rather than science. I didn't know that they weren't supposed to drag their tails or that they had been moved out of the swamp by the Dinosaur Renaissance; all I needed to know was that they were creatures that lived and died a long, long time before I was born, even though my imagination didn't let them rest soundly. I know a lot more about…
laelaps | January 13, 2008Zach has got the latest edition of the Boneyard up for your viewing pleasure (and many thanks to Zach for giving me my own little subsection). The next edition will be up the Saturday after next over at The Dragon's Tales, so get those links to me or Will as they crop up!
gregladen | January 11, 2008Everyone these days knows about the "island effect" where certain animals evolve to a diminutive size because they live on islands. You know this because of the Flores hominid. Now, it has been shown to have operated in a dinosaur.
Thecodontosaurus Thecodontosaurus is also known as the Bristol Dinosaur. It is one of the first named dinosaurs, having been found in 1834, even before dinosaurs were recognized as a phenomenon. It is a diminutive dinosaur that was originally thought to have lived in an arid area of the mainland. Research just published in Geological Magazine shows that…
laelaps | January 9, 2008Wouldn't you know it? I'm in the middle of writing a nice summary on spinosaurid bite mechanics and all hell breaks loose in the journals. Besides the nonsense about Psittacosaurus, there's a new paper just out in Nature featuring a new cuddly little creature called Plumulites bengtsoni, that is if you think ancient armored worms from the Lower Ordovician are cuddly. I don't have the time to blog about it right now, but here's a look at the Plumulites;
Plumulites bengtsoni. From Vinther, J.; Van Roy, P.; Briggs, D. (2008) "Machaeridians are Palaeozoic armoured annelids." Nature, Vol 451, pp…
gregladen | January 8, 2008
From a University of Bristol Press Release: "Rather than being gentle giants, new research reveals that Pleistocene cave bears, a species which became extinct 20,000 years ago, ate both plants and animals and competed for food with the other contemporary large carnivores of the time such as hyaenas, lions, wolves, and our own human ancestors."
Joao Zilhao, Professor in Palaeolithic Archaeology at the University of Bristol, Professor Erik Trinkaus of Washington University and colleagues in Europe made the discovery while dating the remains from Europe's earliest modern humans. Cave bears (…
laelaps | January 8, 2008I'll admit it; I've been a slacker about putting up the Boneyard in a timely fashion. Zach, however, has graciously offered to start things up again with a brand-new edition coming this Saturday, so get your posts to me or to him soon! I also need some volunteers for hosting for the 26th of January and the 9th & 23rd of February, so if you're up to it let me know.
gregladen | January 8, 2008Pumice is rock that is ejected from a volcano, and has so much gas trapped in it that it can float. So when a pumice-ejecting volcano (not all volcanoes produce pumice) goes off near a body of water, you can get a raft of rock floating around for quite some time. By and by, water replaces the gas within the rock and it sinks. Like a rock. So, you can get layers of pumice on the bed of lakes, seas and oceans. A forthcoming paper in Deep Sea Research I describes two such pumice deposits of "Drift Pumice" in the Indian Ocean.
The fact that the two deposits are more or less on the surface of…