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, 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 ( 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 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,, and 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


Springer has a new service which is rather interesting, called CiteULike, which can be found at 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 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 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.

Monday, October 20, 2008

Life's Beginnings

In a quick break from SVP, just thought I'd mention an interesting article in Science that appeared on the 16th. Apparently, two fo Stanley Miller's students were going through his lab after his death and found a couple of samples fom his famous experiment on the creation of organic molecules in the primordial soup and decided to retest them. They found double the number of amino acids that Miller found 50 years ago. 22 amino acids were found, including all 20 of the ones used by living organisms today. They did note that the atmosphere back then did not have as much hydrogen as in Miller's experiment, but it did exist at those levels around volcanic outlets, prompting the idea that time and volcanoes may have helped spur the creation of life on Earth.

Sunday, October 19, 2008

Dinos at the SVP meeting

All of the abstracts for the talks and posters I will be mentioning can be found in the Journal of Vertebrate Paleontology, Volume 28, Supplement to Number 3.
I will start with the dinosaurs because 1) they are cool, 2) they are my favorite animal even though they aren't technically in my field of research any more than any other particular animal, and 3) everybody likes dinosaurs, right?
Schmitz gave an interesting talk during the Romer Prize session in which he looks at the orbits of dinosaurs and, after comparing them with modern animals, was able to determine that, even though most dinosaurs were indeed diurnal like commonly thought, many dinosaurs were most likely nocturnal or cathemeral (active all the time). All the pterosaurs he studied were diurnal, but Syntarsus was nocturnal, and Herrerosaurus and the larger (over 296 kg) herbivores were cathemeral.
Evans showed that hadrosaurine crests were unrelated to olfactory ability in that the olfactory region was not involved in the crest. He also showed that the sound estimated from the crest and the optimal hearing frequency based on inner ear casts matched quite nicely. Combine this with the finding that hadrosaurines had enlarged cerebral hemispheres, making them rather intelligent compared to most other dinosaurs, and the conclusion is that they had a complex social structure and their crests played a role in social signalling.
Tsuhiji discussed the first known complete skull of Avimimus, finding that it was a basal oviraptosaur with the horizontal canal of its semicircular canals being more avian than Archaeopteryx.
Hurlburt discussed dino brains, finding that while their forebrain percentages were in the low avian range, their cerebral EQs (cerebrumin proportion to body mass) placed them between reptiles and birds, but closer to reptiles.
Andy Farke did a decent job ruling out the shock absorber hypothesis for the frontal sinuses in ceratopsians and modern bovids, but couldn't say what if any function they might have had.
Longrich found that having feathers on the legs allowed Archaeopteryx to increase lift and reduces turning radius and drag thereby improving performance at low gliding speeds. He also found the original Berlin specimen had feathers preserved on its legs until overzealous preparators removed them. Interestingly he says this supports the arboreal origin of flight.
This puts him in direct opposition to Dececchi and Larsson, who looked at the anatomy of derived maniraptorans to see how well they compared to known claw or grip climbers and found their anatomy was all wrong to be arboreal, saying that, while they may have gotten into trees from time to time, they certainly weren't arboreal and were scansorial at best.
Zanno reprted a new phylogeny of therizinosaurs based on two new specimens, which broke up the presumed monophyly of therizinosaurs and oviraptors, putting therizinosaurs as basal maniraptora and ecologically convergent with oviraptors. Interestingly, this makes herbivory rather common in maniraptora, so they evolved from hypercarnivores into herbivores and omnivores with the derived manirpatora that were hypercarnivores secondarily derived it.
Barrett reviewed the hypothesis that dinosaurs coevolved with cycads and found no evidence that they either ate them or would have had problems even if they had and no association with large dinosaurs, so absolutely no evidence that dinosaurs in particular had anything to do with cycad evolution.
Carrano did another study of dino diversity in the late Maastricthian and found no evidence that dinos were on the decline in the Western US, but can't say globally as the data just isn't there.
Hayashi found that stegoasaur spikes had thick compact bone but ankylosaurs spikes and clubs had thin bone on their periphery so they clearly were doing something different with them.
Ok, it's getting late and there is much more to say, but for now, I will report on one last crazy thing. Witmer described the first detailed description of ankylosaur nasal passages and the best way to describe them is the crazy straw nose. I can honestly say I have never seen anything quite like it. The nasal passages, rather than having a series of paranasal sinuses, had a crazy twisted tortuous path through the head. Very odd.

News from the SVP meeting

Just got back from the annual meeting of the Society of Vertebrate Paleontology in Cleveland, where I reported on my work, but since I already know about mine, I won't report on it here other than to say it is devilishly difficult to reconstruct soft tissue from sediment traces, but there are things you can lean before prepping out a fossil. While I was gone, I missed the announcement of the first known vertebrate neck in tiktaalik, as reported in Nature (Downs, Jason P. et al. 2008. The cranial endoskeleton of Tiktaalik roseae. Nature vol. 455 (October 16), 925 -929). This is rather important as it provided a great advantage to the animal allowing it to turn its head without completely realigning its whole body. Downs gave a talk about this at the meeting, explaining that the head had several features making it more tetrapod-like, including the lack of an operculum and reduced hyomandibular bone that helped free up the neck and a more complex joints between skull bones reducing their mobility.

In the next several posts, I will relate several of the items I found interesting at the meeting, some of which you may hear about in other arenas, some you most likely won't.

Friday, October 10, 2008

Civic Science Literacy in the United States

Yesterday I got the latest issue of Science News, in which the editorial discussed science in politics. Coincidentally, I also went to a talk by Jon Miller, from Michigan State University titled, “Scientific Literacy and Citizenship in the 21st Century.” His main thesis was that many of our most pressing social and political issues are at their core scientific and that this will only increase as time passes. Unfortunately, most people do not have even a basic understanding of science and as such, can not even understand enough of the issue to intelligently discuss them let alone make policy decisions about them.
Many people have the idea that knowing the science is not required because common sense will allow figuring out enough to adequately make decisions. While that was true a hundred years ago, that is far from reality today. The issues are simply too broad scale and complex for standard common sense to work. Quite simply, if you can’t even understand the arguments, you can’t decide what to believe using rational thought.
His talk had good news and bad news. The good news is that the United States was second only to Sweden in the number of its citizenry that could pass a basic science test. The bad news is that we only rate 25% (for comparison, Sweden was just over 35% and the EU averaged only 15%. We have also improved in the last twenty years as we only rated 10% in 1988. However, with the issues facing us now, having only 1 in 4 of the population able to even begin to understand them is a serious danger to democracy.
So what brought our score down below Sweden? The rank of the US in understanding evolution is 33 out of 34 countries with only 40% accepting evolution, ahead of only Turkey. Iceland was number one with over 80% of their populace conversant in basic evolutionary concepts. The factor most strongly correlated with the rejection of evolution was religious fundamentalism, which actually strongly negatively correlated with science literacy of any kind.
The causes for these scores were seen to lie in two factors: our high schools and our universities. Our high schools rate virtually last in the world. He hypothesized that this was due to the fact that we are the only country to fund our schools using property taxes, which woefully underfunds our public schools. However, this is counterbalanced by our universities, which rate among the best. We are also the only country that requires virtually all college students to take a year of a core set of general education courses which include introductory science courses in addition to the three years required for their major. Apparently, in other countries, students only take the courses relating to their major. Thus, those not in the sciences never need take a science class. Unfortunately, only 28% have a college degree, which is behind many other countries.
He and his colleagues correlated several factors that affected science literacy. Despite what many people seem to think, gender was not a factor and he rightfully disparages the prevalent attitude that girls can’t do math and science. In fact, considering that women now outnumber men in colleges by over 6% and are increasing their dominance in colleges, young women are more likely than men to be scientifically literate.
The single biggest factor (with a correlation of .78) was having had the basic science courses in college. Because of this large effect, he advocated gearing these courses to increasing their effectiveness in enhancing adult continuing education. Other often discussed effects were also evaluated, including internet use with a positive correlation of .39. Religious fundamentalism had the worst affect, with a negative correlation of .2. Interestingly, TV had no effect either positive or negative.
As a case study, he specifically studied attitudes toward climate change. They were only able to account for 30% of the variance, but of that 30%, the overriding factor was political party. Republicans were likely to dismiss it, Democrats were more likely to think it was a serious concern. Of those that were concerned, they were able to account for most of the variance about who tried to do something about it, such as contacting their congressmen to talk about political issues. Being scientifically literate had a correlation of .41, but a bigger influence was seen by having children, with a correlation of .55. Climate change is an inherently long term issue. Apparently, having children causes people to give more consideration to things that affect their kids. Again, religious fundamentalism negatively correlated with concern about climate change. Of course, the majority of religious fundamentalists were Republican.
I’ll just finish this summary of his talk with two thoughts of his. “Civic scientific literacy provides a set of conceptual and practical tools…to make full use of the Internet and related information centers.” One good thing that Bush has done for the country is that “Political scientists no longer argue that is makes no difference who wins the elections.”

Monday, October 6, 2008

Dinosaur/Bird connection even stronger

Vargas AO, Kohlsdorf T, Fallon JF, VandenBrooks J, Wagner GP (2008) The Evolution of HoxD-11 Expression in the Bird Wing: Insights from Alligator mississippiensis. PLoS ONE 3(10): e3325. doi:10.1371/journal.pone.0003325.

This paper, published Oct.3rd, puts another nail in the coffin of the arguments against the dinosaurian origins of birds. One of the biggest arguments used to "disprove" the dino/bird relationship was that, using embryological evidence, birds have digits 2, 3, and 4 on their hands and lost digits 1 and5, but dinosaurs have digits 1, 2, and 3 and lost digits 4 and 5. Morphologically, bird fingers look like digits 1, 2, and 3, just like dinosaur digits. Vargas and crew looked at the activity of the HoxD-11 in crocodiles, birds and mammals. Mammals express HoxD-11 in digits 2-5, but not in 1, crocs express HoxD-11 in digits 2-5, but not in 1. Guess what? Birds express HoxD-11 in digits 2 and 3, but not in digit 1. So birds do not in fact have digits 2, 3, and 4 like the people who disagree with the dino-bird theory. So their biggest argument has now been quite convincingly obliterated. Think we can end this debate now?

Acid makes the oceans louder

In a study in the most recent Geophysical Research Letters, Keith Hestor and crew calculated that the predicted drop in oceanc pH of 0.3 points over the next 40 years will cause a 70% increase in the distance sound will travel in the oceans. It's not really understood why this happens but it is known that acidity increases the sound conductance of seawater. What was surprising was how much the rather modest decrease in pH would affect the conductance.

Life in the Cretaceous polar seas

Karen Chin and several coauthors published an interesting (to me at least) paper in the Proc. R. Soc. B online journal August 19 called "Life in a temperate Polar sea: a unique taphonomic window on the structure of a Late Cretaceous Arctic marine ecosystem " (DOI
10.1098/rspb.2008.0801). Through study of the sediments and fossils within the late Cretaceous rocks on Devon Island, Canada, they were able to deduce that a thriving ecosystem lived in temperate waters in the polar seas. Whereas the modern ecosystem is supported by nutrient upwelling, the paleo ecosystem appears to have been supported by terrestrial forests that contributed abundant nutrients to the marine waters. So, while it may not have been exactly warm, at least there wasn't constant ice. Whatever lived there still had to deal with long cold nights though, but at least there was plenty of food.

Sunday, October 5, 2008

World's Oldest Footprints

Man I wish I could have gone to the Geological Society of America meeting going on right now. A huge meeting with lots of great stuff, such as this talk reported by given today reporting on the oldest known footprints. Soo-Yeun Ahn, a graduate student at Ohio State University presented a poster about a 570 million year old track site discovered in Nevada by his advisor, Dr. Loren Babcock in 2000. the track is apparently a centipede-like creature. Oh well, I am sure that the Society of Vertebrate aleontology will have tons of cool stuff (actually, I know it will, but I am not allowed to say anything about it until it is presented at the meeting because of the news embargo to allow the presenters to be the first to present their cool stuff to the world).

Wednesday, October 1, 2008

Dinosaur had avian air sacs redux

Sereno has come out with a new paper (Sereno PC, Martinez RN, Wilson JA, Varricchio DJ, Alcober OA, et al. (2008) Evidence for Avian Intrathoracic Air Sacs in a New Predatory Dinosaur from Argentina. PLoS ONE 3(9): e3303). In this paper he introduces a new dinosaur by the name of Aerosteon riocoloradensis, which falls out as a basal tetanuran, down with the allosauroids. But the main part of the paper lays out Sereno's view of the evolution of avian air sacs within the dinosaurs. Seeing as Pat O'Connor has published on this topic previously and his office is right down the hall from mine, I was a bit miffed at how dismissively Sereno treated Pat's work. While I have some issues with the paper, not least of which is that he seems to be saying basically the same thing as Pat while dissing him at the same time, I do think he does bring some additional points to the table and advances the discussion. It remains to be seen whether or not his claims hold up, but that's ok, it spurs debate and research, which is a good thing. The paper is worth a read.

Sympatric speciation through sensory isolation

Many people have claimed that new species have to be created by geographic isolation, that is, they do not believe that sympatric speciation (new species arising from a population in the same area) can happen. I personally think that is hogwash and it can certainly happen. A nice case in point is an article in the October 2 Nature by Seerhausen et al. called "Speciation through sensory drive in cichlid fish." Cichlids are amazingly diverse and many species occur alongside other species of cichlids. Seerhausen et al. studied several species that occur sympatrically when considering just two-dimensional geography, but occur at different depths. The species are different colors and their visual sensitivity matches the change in light absorption at the corresponding depth, meaning their eyes are optimized for lack of a better word for the depth at which they live and their coloration shows corresponding adaptation. it is fairly clear that these species all originated from the same ancestor that lived at all depths but then speciated by adapting to specific depths. The case could be argued that this depth separation counts as allopatric, or geographic separation, but I think that would be stretching the definition a bit thin as nothing prevents the fish from swimming throughout all depths other than their preferences.

International Dinosaur Month

Ah, the wonderful days leading up to meetings, when one realizes they have monthsof work to do in a few short weeks. Ok, so I've been bad and there has been lots of cool stuff that has come out, including a new group of whales to go along with a new fossil whale as published in the latest journal of Vertebrate Paleontology, but for right now let me just say that today is the start of International Dinosaur Month. Go hug your local paleontologist and enjoy your local dinosaurian fauna, either by doing some birdwatching or by eating some fried chicken I hope I don't have to tell you that birds evolved from dinosaurs and are thus technically dinosaurs themselves, right?).

Monday, September 22, 2008

12 year old leaps solar tech forward

Wow. Ok, this is not exactly breaking news, as it was first reported via on the 18th, but it is amazing. A 12 year old kid developed a 3D solar cell that collects 500 times the energy as commercially available solar cells and 9 times the best 3d solar cells that have been developed (and not available outside prototypes in labs). It does this by not only collecting visible light, but UV as well and by using carbon nanotubes in a 3D array to better absorb more light and reduce the inevitable dissipation of energy during the conversion and distribution of the energy. Now if only he can get it developed for commercial use.