Wednesday, January 28, 2009

Romanian Taphonomy and Dieing Dinos

Francois Therion et al. have an article in the current issue of Paleo3 (Palaeogeography, Palaeoclimatology, Palaeoecology) called, "Palaeoenvironmental reconstruction of the Late Cretaceous Sânpetru Formation (Haţeg Basin, Romania) using paleosols and implications for the “disappearance” of dinosaurs. I happen to have a fondness for Romania, but besides that, they did something I (and many others) have often said needed to be done: they took a good look at the taphonomic conditions at the K-T boundary. I'll just put what they conclude in their abstract: "The distribution of pedotypes through the Sânpetru Formation reveals small- and large-scale palaeoenvironmental changes associated with the shifting of a complex mosaic of wet and dry habitats in response to shifts in river position on the alluvial plain. However, a major palaeoenvironmental change occurs in the upper Sânpetru Formation, where the region was transformed into extensive wetlands. Such dramatic changes coincide with river competence increase, change in palaeocurrent directions, and dearth of macrovertebrate remains, which had been previously misinterpreted as evidence for the disappearance of dinosaurs at the Cretaceous-Tertiary boundary. These palaeoenvironmental changes, induced by tectonism, are responsible for the shift from preservation of macrofossils concentrated by hydraulic processes into conspicuous lenticular bonebeds in the lower Sânpetru Formation to preservation of microfossil, and more rarely macrofossil, remains in hydromorphic calcareous paleosols in the upper Sânpetru Formation. The consequences of palaeoenvironmental changes on vertebrate preservation mode must be considered in the search for fossils and interpretation of the fossil record."
While I am currently dubious as to how much it will affect our understanding of the K-T extinction, it is not from any problem with their study. There is much more study that needs to be done like this before I think we can make any sort of determination on the taphonomic effects influencing the perception of mass extinctions. The work done before in this regard has mostly been on a broad scale looking for large patterns. But we have really been lacking in detailed studies of the preservation changes at specific extinction events. I hope that others continue this line of investigation in other areas and other times. This is critical but often undervalued research for our paleoenvironmental and evolutionary understanding. When I say undervalued, it seems to be very often something that many people realize is important and will say so, but then tend to ignore it when it comes to their own research and interpretations. So I am quite happy to see this article.

Saturday, January 17, 2009

Neurotypical Neuroscience

There is a new book out called, "Welcome to Your Brain," by the two neuroscientists Sandra Aarnodt and Sam Wang. The book was reviewed on the Today Show, http://today.msnbc.msn.com/id/28644401/?gt1=43001. Sadly, if the review is at all accurate, while the book may be useful for many people, it falls into the same sad trap that a lot of people make. "I think this way, so everyone must think this way." Among their claims, one can not tickle oneself. This is patently absurd. I can tickle myself. I feel the texture of the clothes I wear. I feel the chair I sit on. I know a lot of people that do as well. Course, many of them are considered autistic to some extent. Still, that changes nothing. Just because most people do or do not do something does not give one carte blanche to say that no one does or that something is impossible. I have not read the book and the authors can be forgiven if the reporter terribly misrepresented them. After all, few reporters know anything about science and most are much less concerned with complete accuracy than they are a good story (although even scientists that know better can fall into this category, just see the Smithsonian dinosaur anatomy webpage for a scientist that doesn't let inaccuracy get in the way of the story, see if you can spot the error he made). However, if the review accurately reflects the beliefs put forth in the book, it is a definite flaw. When trying to make a complex issue understandable to the lay public, it is very easy to go too far and reduce things to incorrectness, a pattern I believe we should be ever diligent to prevent. We can not allow ourselves as scientists to spread falsehoods in service to a broader purpose. Some people will say, it's easy to say and be all idealistic, but when the rubber meets the road, he will do the same thing. Actually, that's not true. This is an issue that I have struggled with many times. It is always more ethical to be as accurate as possible. It is harder and many times one must qualify one's statements as making explicit the comments are in general and not always true, but as scientists, particularly those of us that reach out to the public, we have a duty to be accurate. Otherwise, we damage the credibility of all scientists. So many people have a poor opinion of scientists and science in general, in part, because of this very thing. It is worth the extra effort to be as accurate as we can and not allow ourselves to say things we know to be false just to simplify a point (and if at any point, you see me making the same mistake here, please let me know so it can be corrected, it is easy to overlook this sort of thing in one's own writing, which is what good editors are for).

Friday, January 16, 2009

Extinctions Due to Confluence

I have said for a long time that the whole idea of pinning mass extinctions on a single event was not constructive. Rather, it made much more sense to think of the global ecosystem as fairly resilient, such that true mass extinctions would only occur when multiple events coincided. Apparently Arens and West agree with me. They published a paper in the December issue of Paleobiology (http://paleobiol.geoscienceworld.org/cgi/content/abstract/34/4/456) indicating that mass extinctions occurred when a "press" event, such as extensive volcanism stressing the ecosystem over time, coincides with a "pulse" event, such as a bolide impact, that causes acute and sudden catastrophe. The 1-2 punch is what causes the mass extinction. Finally, someone has published a good statistical and rigorous study demonstrating what I have been saying for years but never actually did a rigorous analysis to prove. Good for them.

Wednesday, January 14, 2009

Dinosaurs: one poached, one paternal

A new ankylosaur was officially described in the Journal Current Science called, Minotaurasaurus ramachandrani, which can be found at http://www.ias.ac.in/currsci/jan102009/65.pdf. The specimen is notable for its wonderful preservation and completeness of the skull, but mostly it is notable for the fact that it is a poached, completely illegal specimen. It was bought by a private individual at a gem and mineral show. The only locality data available is an inference of the Gobi Desert, somewhere in China or Mongolia, based on rock around the skull. Given that it is illegal to take fossils out of those countries, it had to be smuggled out. Therefore, the specimen is stolen property. The Society of Vertebrate Paleontology would not allow such a specimen to be published as they take a dim view of fossil theft.
The authors acknowledge the legal difficulties of the specimen, but, quite rightly I believe, say the specimen is too important not to describe and get out into the scientific literature. I am sure this article will add fuel to the debate about commercially sold fossils. As it stands, illegally obtained and privately owned specimens are generally not allowed to be studied as the important locality information is almost always unknown and doing so would seem only to encourage unethical commercial fossil dealers (this is not to say that commercial fossil dealers are all unethical, there are a few that follow the laws and do their best to collect pertinent data as the fossils are collected) as the studies and publicity therby raise the value of the specimen under study. Because privately owned fossils are off limits for study, the best fossils are lost to science. Additionally, because paleontologists are more rare than the fossils they study, most fossils are not collected in time and are simply weathered away.
Even though the SVP leaders take a hard line against commercial fossil dealers and would prefer that all fossils are given to scientists to study with none being allowed to be in private hands, I disagree. Professionals can not possibly collect all the fossils. Depending on only professional paleontologists with their meager funds to do all the collecting means very little fossil collecting will be done and most fossils will be lost. However, I agree with them that the fossils are a national heritage and should be accessible for use. Therefore, I propose that collecting fossils remain legal on private land, legal on public land with the proviso they must work with a professional paleontologist, and all discoveries be accessible to researchers. Thus, the fossils could be bought and sold, but the owners must allow researchers to study the specimen, although they do not have to surrender the specimen. I would also require that fossils brought into the country are treated like we do any archeological find. The laws applying to them in the country of origin apply here. If the fossil is smuggled out of a country, the fossil is confiscated with the smuggler arrested and tried as per any other piece of stolen property and the buyer arrested and tried for possession of stolen property.
The laws concerning the illegal smuggling of fossils into the country need to be vigorously applied. But rather than take a hard stance against all fossil trade, professional paleontologists would do much better by developing a collaborative relationship with the commercial dealers, who will always have more funds to collect fossils. A proper collaborative effort would greatly expand the fossils known to science. I for one am sick with the knowledge that a great deal of information that we as individual scientists know about, but can't tell anyone else because the information came from a private or stolen specimen.

Anyway, enough of that soapbox. The other news is an article in the Dec. 19 issue of Science by Varrichio and colleagues on dinosaur dads. I am somewhat amiss that I missed this and only found out about it via Science News. Varrichio et al. looked at the bones of a Citipati and Troodon that were found over nests and found that neither one showed evidence of medullary bone, which female birds form during egglaying. While they acknowledge that not finding exclusive female markers does not prove these are males, the view is bolstered by the fact that ratites are also predominantly paternal. Ratites include the large, flightless birds such as the ostrich and are the most closely related birds to the dinosaurs. Not only are ratites paternal, but they have very similar clutch sizes to that seen in Citipati and Troodon.
So it really isn't terribly surprising if this is indeed the case, at least for the more derived theropods. But it is good to see it being examined critically rather than just being assumed by inference. Now it remains to be seen how far down the lineage this extends, considering the extensive phylogenetic distance covered by dinosaurs.

Wednesday, January 7, 2009

Dinosaur Cranial Kinesis and a Wizfolio correction

In the December issue of J. Vert. Paleo, Casey Holliday has finally gotten his paper on cranial kinesis in dinosaurs out. It is a thorough study of what it takes to make a skull kinetic, providing four criteria for determining kinetics. Three have been commonly used, that being synovial basal and otic joints and protractor musculature. However, these are insufficient by themselves without "permissive kinematic linkages" as I talked about in an earlier post on Casey's work. The problem with the first three criteria is that Casey has found them pretty much throughout Diapsida, including in animals with clearly akinetic skulls. I should point out here that he rarely says animals were akinetic, he refers to those animals meeting one or more but not all four criteria as "partially kinetically competent", meaning they have some of the items needed but lacking enough to actually permit movement. All in all, a fine and much needed study.

In other news, someone has pointed out to me that Wizfolio does indeed allow easy sharing of pdfs and other documents between colleagues. Now if it only allowed full text search capabilities.

Tuesday, January 6, 2009

Online reference managers

Seems there are quite a few online reference managers out there now. Many of them are great. Unfortunately, none of them have all the features I would like. But considering five years ago, there wasn't anything, we can hope that in the near future someone will combine the best ideas into one awesome package.
In the meantime, ones that have made an outstanding start are zotero.com, Labmeeting.com, and https://home.wizfolio.com. Zotero is great because it works through your web browser and collects reference information for a wide variety of sources, including pdfs, webpages, and images among others. It can't however collect reference information from citations in pdfs, nor can it do full text searches. Labmeeting allows full text searching along with searches on PubMed and Google Scholar, as well as easy sharing among colleagues. It only does pdfs though, and does not plug into word processors. Wizfolio seems the best at collecting reference information easily, including from inside pdfs, handles pdfs, webpages, images, what have you. It will even search out pdfs on the web for you. It sadly does not offer full text searching, which is a critical feature for me. It also is a standalone, not easily combinable with other people, so it is not as easy to share pdfs with people as it is on Labmeeting.
All of them offer easier methods of entering references than CiteULike in my opinion.
Now if only all these products were combined, we would have an absolutely brilliant program.

Friday, January 2, 2009

CiteULike

Springer has a new service which is rather interesting, called CiteULike, which can be found at citeulike.org. It allows one to easily (the keyword here, using just a few clicks) create an online database of articles they find online. The interesting thing about it is that it also allows other people to have access to your online library through the formation of groups. The libraries of individuals within the group form a shared library accessible to anyone in the group. Groups are easy to set up and can be set as either open for anyone to join or restricted so that people have to apply for membership. Few groups right now have many people, but as more people use the cite, the more useful it will be.

Thursday, January 1, 2009

Happy New Year

Happy New Year! yes, it has been a while since I've posted. On the plus side, I did finish a manuscript. Yay me:) On the negative side, I have done precious little writing on my dissertation. My resolution this year is to write much more. What inspired me to post again? Finding out that my blog pops up at the top of the list for hadrosaur chewing. Apparently people do read this after all:)

Ok, on to stuff people might be interested in. Lots of stuff has come out recently. A couple of new dinosaurs recently, a new Gondwanan dromeosaur named Austroraptor cabazai, by Novas and crew in Proc. Roy. Soc. B, and Albertonykus borealis, in Cret. Res. by Longrich and Currie. While the dinos are cool and all, I wish people would stop overhyping their stuff or vastly over-reaching their data. While Austroraptor is interesting, I would hardly call it "bizarre", but that's just me. I also think Longrich and Currie went rather far beyond what we know about the animals and their ecosystems in their interpretations. Indeed, it is my personal opinion that a few of the statements in the paper went beyond what we can know, which I think is something we as scientists really need to be wary of. No disrespect meant to them, because I hold great respect for all the authors of these papers. Hell, Currie is in my top five most respectable and influential paleontologists and has deserved every bit of praise he has been given. But I think we need to be very wary of making statements that go beyond what we can really demonstrate. Sadly, the game is played these days such that doing so is very hard to do and still get your material published and noticed. But for the good of us all, it is a goal we must strive for.

Moving on, I must say that the dino paper I am most excited about is a paper that has gotten a good bit of press by Witmer and Ridgely on the paranasal sinuses of predatory and armored dinosaurs in the Anatomical Record, vol. 291. The most exciting part about the paper for me is the crazy straw nasal passage seen in Euoplocephalus. It is truly freaky, never seen anything like it before and opens up a lot of possibilities in physiology that seriously need to be addressed. I highly recommend this paper. If you want to see more of the data, Witmer has a bunch of 3D files on his website at http://www.oucom.ohiou.edu/dbms-witmer/Euoplocephalus_movies.htm. Oh, and they also have a chapter in the book by Currie et al. on Pachyrhinosaurus which is neat too, but not nearly as scientifically interesting to me.

Ok, enough about dinosaurs. You should really check out NewScientist.com. They have a great article on virtual dissection. I so want one of those CT scanners with dual x-ray sources. That sort of machine would make my work much easier. The images they show are truly fascinating. There is also an article on the wierdest animals of the year, including a one ton rodent and a frog that breaks its bones to produce claws that then cut through its own skin. Definitely worthy of being on the list. I also found the sea slug that absorbs functioning chlorophyll from the algae it eats allowing it to gain energy from photosynthesis. Funny thing about that, I wrote a story fragment years ago about genetic research allowing people to photosynthesize. In my story, it worked, except for the problem that the people still ate like normal because that is what their bodies were designed to do, which caused them to die of gross obesity. Apparently, the sea slugs are smarter than that.

Finally, I would like to bring to people's attention an article published in PLOS Medicine by Young et al. called "Why current publication practices may distort science." It does a good job of laying out several problems in science publication practices today and offers some suggestions for improving them. He nicely discusses the "winner's curse" problem in which the winner of an auction pays more than the item is worth. In this case, he makes an analogy with this to the problem in science that the more extreme and positive the results, the more likely it is to be published and cited. Results that are less significant or negative have a much harder time getting published, even though they are more often valid. It also causes "herding", in which the more cited papers can actually drive other researchers into similar avenues of research. this is basically the academic version of trendsetting. What works for one serves as the bandwagon others jump on, and which allows their papers to be published more easily. This however, means that avenues of research are then limited by what has been published before and can inhibit innovative research. This is a topic that everyone who uses scientific data should be cognizant of, as everyone has a stake in the data being published, whether they realize it or not. As just one example, the medicine we take is based on positive published results, but we don't know how many negative studies have gone unreported. Think about that next time you pop a pill for an ailment.