It’s almost that time again…

30 08 2007

The next installment of the paleo-carnival The Boneyard is coming up this Saturday, and it will be hosted by my good friend Zach over at When Pigs Fly Returns. Be sure to send your submissions to him or to me by Friday evening if you want in on the osteological action.

Also, my friend Brian of Clastic Detritus (formerly …Or Something) has started a earth sciences-based carnival with the absolutely wonderful title of The Accretionary Wedge (it ranks right up there with Highly Allochthonous as a title). The first edition is all about how bloggers came to be interested in the earth sciences to begin with, so if you’re a geo-blogger be sure to contribute to this new conglomeration.

And, lest I forget, the anthropology carnival Four Stone Hearth is up at Hominin Dental Anthropology and Tangled Bank #87 is up at Balancing Life. I really need to get back on top of when carnivals are going up to get some more posts out there…





The Boneyard #2

4 08 2007

Welcome, fellow boneheads, to the 2nd edition of The Boneyard!

– Some titanosaurs, among the largest sauropods that every lived, had osteoderms along their backs, and a new preliminary poster from Thiago da Silva Marinho in Nature Precedings suggests that while the osteoderms probably didn’t provide huge adults sauropods much protection, they were likely much more closely packed in newborn titanosaurs, offering important protection along their back. Paleontologist Julia Heathcote (the Ethical Paleontologist) has the scoop on the little armored sauropods.

– Michael of the Dispersal of Darwin has graciously pointed out some of Charles Darwin’s thoughts on the “position of the bones of Mastodon (?) at Port St Julian.” I just can’t get enough of that old-time paleontology.

– Chris Harrison, in addition to having the best blog name ever (Interrogating Nature), has an old cartoon featuring a famous, artifically-elongated Basilosaurus.

– Just about any picture that you’ll ever see of a Deinonychus features it as part of a well-coordinated pack, disemboweling some poor Tenontosaurus or other ornithiscian dinosaur. But how realistic is this picture? Zach Miller of When Pigs Fly Returns fills us in on some new research that contradicts the popular conception of pack-hunting dromeosaurids.

– The wonderful blog Prehistoric Pulp has a review of the recent book Dinosaurs in Fantastic Fiction, which has appeared (somewhat serialized) in the last few issues of Prehistoric Times magazine. Definitely give this one a look if you want to keep up on paleo-inspired fiction!

– The good folks at the Everything Dinosaur store and blog ask “Did the Birds wipe out the Pterosaurs?”

– The extant coelacanth Latimeria chalumnae is one of the great iconic creatures of evolution and paleontology, and Julia fills us in on some recent discoveries involving not only living coelacanths, but fossil ones as well.

– The subject of whether Homo sapiens and Homo neanderthalensis ever interbred continues to be controversial, and Afarensis points us to a new paper covered by National Geographic that claims to be evidence for such canoodling of the two species.

Dr. Vector wants to figure out his Cope-Marsh number, and I would too.

– Matt from Behavioral Ecology Blog astutely points at yet another error ScienceDaily has made, this time regarding human evolution and China.

– The hydrothermal vents of the deep sea have been thought to hold clues about the evolution of life on earth since their discovery along the Juan de Fuca Ridge off the Galapagos Islands in the 1970’s, and now some new research has come out about Precambrian “black smokers.” Chris of Highly Allochthonous has the details on the newly published research.

– A Mastodon with absolutely ENOURMOUS tusks was recently uncovered in Greece. Catch the story (along with a classic AMNH picture) over at Living the Scientific Life.

– One of the classic paleo-art images is of a pterosaur skimming the water’s surface, trying to catch a fish. New research shows that this is likely more fantasy than reality, however, as outlined over at microecos (with a spiffy old picture of a “ropen” attack, to boot!)

– The recent flooding in England made headlines, but recent research has shown the importance of more intense past flooding during the Pleistocene to parts of Europe. Not Exactly Rocket Science has the summary.

– One of the most famous head-scratchers in paleontology has been how saber-toothed cats and their relatives could have used their massive fangs to kill prey. The Raptor’s Nest offers some insights on this based upon some up-and-coming research.

– Darren of Tetrapod Zoology has an absolutely GORGEOUS Mike Skrepnick painting of the Bearpaw Sea during the Campanian. Do yourself a favor and check it out!

Will didn’t get a chance to get a new post in for this edition of The Boneyard, but here’s a slightly more-fossilized post on the “Dinosaurs of Darkness.”

– And, lastly, Jeremy of The Voltage Gate presents us with some “vintage” paleo-art.

That about wraps up it for the 2nd edition of The Boneyard. The next edition will be coming up the Saturday after next, moving over the the Hairy Museum of Natural History and The Ethical Paleontologist in the near future, too. If you’d like to submit to the next edition or host sometime, you know what to do.





In search of Deep Time

28 07 2007

In reading Gideon Mantell’s Medals of Creation Vol. I, I happened across this passage, quoted from Charles Lyell’s Principles of Geology, which is in turn a translation from a 13th Century Arabic manuscript, describing how difficult it sometimes is to understand that the earth as it is now is something novel, and its history extends far beyond the life of any man, family, or civilzation;

“I passed one day by a very ancient and populous city, and I asked one of its inhabitants how long it had been founded? ‘It is, indeed, a mighty city,’ replied he; ‘we know not how long it has existed, and our ancestors were on this subject as ignorant as ourselves.’ Some centuries afterwards I passed by the same place, but I could not perceive the slightest vestige of the city; and I demanded of a peasant, who was gathering herbs upon its former site, how long it had been destroyed? ‘In sooth, a strange question,’ replied he, ‘the ground here has never been different from what you now behold it.’ ‘Was there not,’ said I, ‘of old a splendid city here?’ ‘Never,’ answered he, ‘so far as we know, and never did our fathers speak to us of any such.’

“On revisting the spot, after the lapse of other centuries, I found the sea in the same place, and on its shores were a party of fishermen, of whom I asked how long the land had been covered by the waters? ‘Is this a question,’ said they, ‘for a man like you? this spot has always been what it is now.’

“I again returned ages afterwards, and the sea had disappeared. I inquired of a man who stood alone upon the ground, how long ago the change had taken place, and he gave me the same answer that I had received before.

“Lastly, on coming back again, after an equal lapse of time, I found there a flourishing city, more populous and more rich in buildings than the city I had seen the first time; and when I fain would have informed myself regarding its origin, the inhabitants answered me, ‘Its rise is lost in remote antiquity – we are ignorant how long it has existed, and our fathers were on this subject no wiser than ourselves.'”

How fortunate are scientists today who recognize that not only have empires risen and fallen, but so have the seas and all manner of extinct creatures. Sometimes when riding on the highways in the southern half of New Jersey, I wonder what it must have been like during the late Cretaceous, my minds eye inserting massive Hadrosaurus browsing on the side of the parkway, a stealthy Dryptosaurus lurking somewhere in the shadows of the pine forest beyond the barrier. Even when working at the Inversand Pit, uncovering marine crocodiles, ratfish, turtles, and mosasaurs, sometimes I stop and imagine myself standing on the bottom of a 100-foot-deep coastal shelf, watching a Mosasaurus maximus or Thoracosaurus (a marine crocodile) swim by. Still, even though I can create this vignettes, if I were to try to think sequentially backwards, hitting every century from now to the beginning of the Triassic, I don’t think I could do it; it is almost to my advantage that there are divisions in the rock that give paleontologists look at parts of time, as a continues record would be very hard to categorize indeed. In fact, many of the major divisions in geological strata are distinguishable because of the change in fauna, and Mantell especially notes this in the Permian/Triassic division in his 1853 book.

Call it childish if you like, but I do find it liberating to let my imagination run wild in Cretaceous New Jersey at times, pondering modes of behvior, colors, and landscapes I’ll never get to see firsthand. Perhaps this is part of the allure of studying ancient vestiges; regardless of how many scientific papers I read or the tentative qualifications I will have to make in future publications, the Mesozoic lives in my head, just as I’m sure that it does in the minds of everyone else who’s acquired an attraction for fossils.





Countering Creationism, Part III; Tale of a T. rex

17 05 2007

I could scarcely hide my frustration when I laid eyes on the bulletin-board announcement; the “Dino Pastor” was coming to my church. Well, not exactly my church (I attended a nightly non-denominational service), but the home church of the services I attended. I promptly ripped down the poster, emblazoned with the image of said man of faith on the back of an oversize dromeosaurid, and later that evening I logged onto the “Declare God’s Wonders” website to see just what I would be up against. In viewing several of the video clips available, the Rev. Paul Veit seemed to employ various slides and rhetorical devices employed by Answers in Genesis, as well as the old creationist stand-by of quote mining. Now even more incised than before (and after conferring with my own church’s staff to make sure I was not unduly rude or polemic in my message) I sent the church’s head pastor a long list of inaccuracies and problems with Rev. Veit’s program, offering to give a corresponding lecture on evolution if he deemed it fit. He did not, and so I found myself sitting a few pews back from the front on a gloomy October Saturday, thumbing through my copy of The Dinosauria, waiting for the kid-oriented lecture to start.

I could go on about the inaccuracies reported by Rev. Veit in his presentation (i.e. that Icthyosaurs were fish; that a columbian mammoth at the Waco, Texas mammoth site was trying to rescue his “wife” from rising mud; that Archaeopteryx may very well be a hoax; etc.), but what initially struck me was a small teddy bear, enriched with minerals, sitting on a table in front of the podium. I do not remember all the details of the bear’s origins, but (if I recall correctly) it fell into an underground spring and remained there for about two years, minerals from the spring seeping into the fabric during that time. While all this teddy seemed to convey was that if you drop one into an underground spring, don’t expect something soft and fuzzy to come back out. Rev. Veit did not see it this way, however; this mineral-fortified child’s toy was proof that fossilization could happen far faster than “secular scientists” claim, and so the bones of dinosaurs really could be less than 10,000 years old. At that point I wanted to approach him, present my left leg, and say “Here’s the other one, why don’t you pull it, too.”

Although Rev. Veit’s little display was entirely wrong about fossils, it did reflect the commonplace misunderstanding of what a fossil is and how it comes to be. During the first lecture of a course on paleontology (as well as one on dinosaurs I had taken with the same professor two years before) one of the first questions that was asked the class was “What is a fossil?” Usually the answers started with “A bone that has been at least partially replaced by rock,” to which is in some sense true but is far too narrow a definition*. After a moment or two someone usually would suggest that eggs, tracks, or shells should be included as well, but what about age? If I found a pig’s rib from colonial America in my backyard, would it count as a fossil? No, not at all (although if I put it back it could, in time).

The answer which the professor revealed (and which I will use as the operation definition for this post) is that a fossil is any preserved trace of a prehistoric organism. The burrows that belie the intense bioturbation of the Inversand Pit in New Jersey are just as much fossils as the mosasaur vertebra I found lying on top of a “junk pile” (a mound of sediment already mined, but usually containing plenty of fossil material), and the exquisitely-preserved frozen-mammoths from Siberia most certainly count as well.

Navasink
Burrows underlying the end-Cretaceous “Main Fossiliferous Layer” at the Inversand Pit in New Jersey. These burrows are fossils just like a dinosaur bone is a fossil, and the orange color is from iron oxides from the Navasink Formation brought down by water. Photo: Brian Switek

Note that nothing has been said about the level of mineralization, which varies from one fossil to another. Sometimes you find a dinosaur bone and it’s been entirely replaced by minerals; such remains are referred to as being “petrified“, feeling considerably heavier than bone that is often displayed in museums. In fact, sometimes the minerals that incorporate into bone create fossils that are even more valuable than the skeleton itself; in Sea Dragons, author Richard Ellis tells of a skeleton of the plesiosaur Leptocleidus that had been at least partially opalized!

Other times, however, exceptional preservation of soft-parts occurs (see my post on the Solnhofen limestone for more on this) and we are given an unprecedented look at structures or organs normally lost due to taphonomic factors (i.e. scavengers, bacteria, weathering, etc.). Such is the case with a particular Tyrannosaurus rex thigh bone investigated by Dr. Mary Schweitzer which revealed the preservation of some soft anatomy previously unheard of from a dinosaur, and Young Earth Creationists wasted no time using her work to support their own interpretation of a literal Genesis account and a 10,000 year old planet. Paul Humber is one such creationist, and he certainly doesn’t hesitate to condemn scientists or point fingers. In Reason #23, the one I’ll do my best to unravel today, he self-righteously states;

Reason #23: The Bible speaks of those who suppress the truth in unrighteousness. Dinosaur tissue has been extracted from bone fossils and has been found to be both soft and flexible. This was a surprise to the evolutionary scientists studying the fossils; they seem unwilling to admit that this evidence, at least on the surface, seems to support biblical chronology and clashes with evolutionary faith that dinosaurs are millions of years old. If some affirm that it is merely soft, pliable polymer, why do they not go the next step and submit it to AMS testing for C14?

It’s odd that Humber does not mention Mary Schweitzer or the species of dinosaur specifically in his assertion, but didn’t have a problem quoting her out of context in a summary of his book Evolution Exposed on Amazon.com. That point aside, wonderfully preserved dinosaurs are always a marvel but hardly anything new; “mummifieddinosaurs have been known since at least 1912, and many of the dinosaurs coming out of Liaoning, China are well known to exhibit such miraculous fossilization that their feathers leave no doubt as to the evolutionary relationship between dinosaurs and birds. The Schweitzer Tyrannosaurus (or MOR 1125 as it’s known in scientific circles), however, is different in a very special way. Rather than preserving skin impressions or aspects of the soft anatomy etched as a mold or cast in rock, it appears that MOR 1125 had actual tissue inside the marrow cavity of one of its thighbones, although the discovery was made because the bone was reluctantly broken in order to better transport the fossil. What is curious is that it seems part of the “conventional wisdom” that all Hell Creek Formation dinosaur bones (where the Tyrannosaurus was found) have a distinct organic odor to them. In an article about her find in Discover, Schweitzer recalls the following;

“It smelled just like one of the cadavers we had in the lab who had been treated with chemotherapy before he died,” she says. Given the conventional wisdom that such fossils were made up entirely of minerals, Schweitzer was anxious when mentioning this to Horner. “But he said, ‘Oh, yeah, all Hell Creek bones smell,'”

Could it be that there is something about the Hell Creek Formation that has preserved organic material within many of the fossils? I think it’s a fair question to ask, especially if there seems to be an “organic odor” that would signal some level of decay. The problem is that some bones would have to be broken or sliced open to confirm this, something that many paleontologists may be loathe to do (and I don’t necessarily blame them!). Still, perhaps there should be a re-examination of fossils from Hell Creek languishing on dusty museum shelves; surely there are some that could be spared to help determine if this is an isolated phenomena or there is something significant going on in Hell Creek.

Such an observation raises an important point, however; just how fast does fossilization occur? The answer is “Well, it depends.” There are various modes by which fossils can come to be, but rather than write a treatise on fossilization I’ll focus on what is pertinent for dinosaurs. To the best of our understanding, after a deceased dinosaur becomes covered by sediment (it helps if this occurs quickly, as the result of local flooding, a mudslide, a sandstorm, a riverbed/ocean bottom, etc.) mineral-carrying groundwater seeps into the tiny spaces in the organism over time, leaving minerals in those spaces, and so bone is converted into mineral. As hinted at earlier, however, the extent to which this happens varies, sometimes producing entirely mineralized skeletons and other times (as with the Schweitzer T. rex) mineralization is not completed. Fossilization is not an all or nothing process (although many popular books seem to treat it as such), and and so the appearance of tissue in a bone does not automatically render the scientifically established age of the earth to be fraudulent or suggest that Tyrannosaurus munched on coconuts in the Garden of Eden.

So what about the “soft” tissue? Well, Humber makes a very common creationist mistake by asserting that “Dinosaur tissue has been extracted from bone fossils and has been found to be both soft and flexible,” which shows that he did not read Schweitzer’s 2005 paper on her findings. There’s really no excuse; it’s available for free through the website of the journal Science, and the second sentence of the materials & methods section explains that Schweitzer did not stick in her thumb, pull out some Tyrannosaurus soft tissue, and say “Gee what a good girl am I” (and yes, I am aware that Schweitzer began this study under the guidance of paleontologist John “Jack” Horner). The opening of the supplement reads;

Small (0.05-2 inches width) fragments of untreated compact and undescribed (1S) endosteally derived bone tissues were separated from Tyrannosaurus rex (MOR 1125) femur and collected under a hood, using aseptic methods. Tissues were demineralized (0.5M EDTA,pH 8.0) for 7 days, changing buffer daily. Material remaining after demineralization was rinsed with phosphate buffer (PBS, pH 6.8) and imaged using a Zeiss dissecting scope with a digital camera and Axio Vision Software (other dinosaur specimens were demineralized according to this protocol but no further analyses were undertaken for this study).

Rather than putting her hand in a pile of goo, Schweitzer separated the tissues and tried to remove as much mineral material as possible, leaving only the organic material behind. Indeed, this dinosaur (like many) was still in the process of fossilization when extracted from the ground, and there was significant enough mineral material around the tissues for Schweitzer to spend time dissolving them. Given that things were not so simple of Humber suggests, what exactly did Schweitzer find?

First, it should be pointed out that this more recent find is often confused with one Schweitzer made a number of years earlier. In June 1997 Schweitzer published a paper in the Proceedings of the National Academy of Sciences entitled “Heme compounds in dinosaur trabecular bone“, and that paper was seized upon by creationists as well. What the 1997 paper reflects was the discovery of hemoglobin remnants and other degraded material from blood, but not actual hemoglobin or red blood cells.

A similar misunderstanding occurred due to media coverage following the 2005 paper; even I couldn’t quite figure out what exactly was found (or not found). In comparison with prepared ostrich tissues, it seemed that Schweitzer had uncovered corresponding tissues from the dinosaur bone, notably blood vessels and osteocytes, although the authors admit towards the end of the PNAS paper that they could not be sure to what extent the original cell materials were present. It has even been suggested that the remaining material was essentially fossilization at a new level, preserving vessels and cells instead of the more familiar fossilization of large structures.

Two new studies released this year (one by Schweitzer, one by John Asara, both appearing in the same issue of Science), however, point to the preserved tissue being original, at least in part. I initially posted about this story a few weeks ago, and while the studies seem to give stronger evidence for organic material in the bone (and once again confirming the dinosaur-bird link) there is still some amount of uncertainty among scientists as to how reliable the results of the protein analysis are. Yes, what were recognized as collagen proteins were collected and sequenced, but more proteins will have to be sequenced before we can be certain of the results of the studies undertaken by Schweitzer and Asara; while the Tyrannosaurus proteins were closest to those of a chicken, they were also fairly close to frogs and newts (the next matches) when I would have expected crocodiles as the next best match. After I originally voiced this opinion I was told that crocodiles were not in the database for comparison, but hopefully they will be soon as how the Tyrannosaurus protein matches up with that of another archosaur. Regardless of how accurate these studies are, they are certainly blazing a new trail in paleontology, and we would be foolish to discount the studies as this is a new area of research as far as dinosaurs go. Scientists should remain cautious, but the work of Schweitzer and others in the field should be encouraged; the more data we collect the better able we will be to solve the puzzles presented to us in the dinosaur tissue.

So, what then of Humber’s challenge as to why the bones have not been submitted for C14 dating? While Humber asserts that evolutionists somehow control consensus over the age of the earth, nothing could be further from the truth; evolutionary biologists often are not the ones running tests on the age of the earth, nor do they dictate the age of sediments to geologists. Beyond this obvious truth, and the fact that stratigraphy, the relative position of fossils, and radiometric dating all support the late Cretaceous age of Schweitzer’s Tyrannosaurus, Humber’s challenge makes no sense.

In the question prior to the one being addressed (which I will deal with in due time), Humber essentially calls scientists “chicken” for not using the most up-to-date carbon 14 dating techniques; if they’re so sure about their dates, why don’t they submit their fossils for testing? To put this sort of question in context, it would be like me going to a psychic with my brothers and sisters and getting an “aura reading” (or whatever the hell they do in the process of fleecing people) to make sure I was really related to all my siblings even though I’ve lived with them all my life, seen them the day they were born, have the independant observations of anyone who knows my family, and share obvious physical characteristics with them. Why would I waste my time and money undergoing a test that isn’t going to work in an attempt to confirm what is already grossly apparent? Carbon 14, even advanced AMS carbon 14 dating, only works with samples about 60,000 years old or less; if we dated a dinosaur bone of course we’d get faulty number back, which creationists would probably claim proves their point. I have to track the paper down, but I recently spied a CRSQ paper claiming to use carbon dating techniques to determine the age of a dinosaur bone, and so the “scientist” apparently undermind their own effort by picking a technique that he must have known would give him “young” (and wrong) dates!

The age of the Schweitzer rex isn’t based upon just one radiometric test, but many independent radiometric tests using various methods as well as paleontologists climbing all over the Hell Creek Formation for a century; if there was some big controversy about how old the formation was (or if it really was 10,000 years old or less) why has no one but the creationists mentioned it? I find it hard to believe that so many scientists over so long a time would all be “in” on a cross-disciplinary conspiracy to keep evolution firmly established in society, and if we are to dismiss the work of hundreds (if not thousands) of chemists, physicists, geologists, paleontologists, and biologists who know the Hell Creek Formation well, why not throw science as a whole out the window as well? No, creationists know such a move would be suicide, so they will continue to try and be backseat drivers to the rest of the scientific community, but I doubt anyone is going to stop and listen to their directions.

Once again, Humber seems to have based his argument on faulty assertions and popular articles rather than examining the papers for himself. Sure, he’ll be quick to claim that Schweitzer’s work supports his own worldview, but if Humber really has read the PNAS and Science papers he either did not understand them or chose to ignore their contents; I’ll leave you to decide which is worse.

For an in depth review of other professional creationists trying to take on Schweitzer’s work, check out Gary Hurd’s TalkOrigins piece “Dino Blood Redux

*In past centuries, however, fossils were considered to be anything that came out of the ground (the word means “dug up” in Latin), and so various rocks, rocks that looked like certain parts of the human anatomy, bones, shells, and nearly anything else that had been underground for some time were called “fossils.”





Painful & Purple Prose: Omphalos

30 04 2007

Late Sunday afternoon I was finally able to close Philip Henry Gosse’s pretentious creationist work Omphalos and relieve the pain I had been putting my brain through. I must admit that I did not read every single page, however, as Gosse makes a point of taking the reader on a walk through the Creation just after it had been “called into being”, picking various examples from the plant & animal kingdoms and explaining how the age of an individual is determined. After a long discussion of how old the elephant, palm tree, or beetle in front of the hypothetical tourist is, Gosse triumphantly exclaims that any such assertion would be wrong being that we know that all life is not even an hour old.

Gosse does try very hard to reconcile geology with church doctrine, but alas, unless one already accepts a 6 day creation event (although Gosse makes a point of not saying whether this event happend 6,000 years ago or 6,000,000,000) Gosse’s entire premise falls flat. To save you the trouble of reading the work yourself, Gosse accepts that God “called into being” all life on the planet as well as creating Earth itself. He also (obviously) rejects “transmutation of species” and so all elephants were always born to elephants, and at the moment of creation only a just-sexually-mature adult would have appeared being that such a stage of life is the most perfect (the same goes for the rest of life, including us). What about fossils? Well, just as God would have created all adult beings with the vestiges of age, so too would God have created the world as if it were really ancient, as if there was no other way to do it (dinosaurs and other fossils being the equivalent to a tree’s growth rings). Gosse does cover his bases, however, and explains that species too have a life cycle, and the elephants of ancient times were just another stage in the continuous and unbroken lifecycle of elephants altogether. Screwy, ain’t he?

Obviously Gosse’s work did not have the impact he was wishing for, giving the faithful the impression that God was a deceiver while asking geologists to accept that they are finding the vestiges of creation in fossils rather than animals that once lived on earth. The whole book could have been written in about 25-50 pages, but Gosse goes to great length to lay out the arguments of others and then to use example after example after example in an attempt at straw man arguments. Gosse’s folly, however, is that he really sets up “stone man” arguments; he wants to make those who don’t accept Creation look like fools, only ending up looking foolish himself. Even beyond this silliness, Gosse’s writing style while walking the reader through the Garden of Eden is laughably pretentious. Here’s an example during an encounter with the ideal horse;

See this Horse, a newly created, really wild Horse,

“Wild as the wild deer, and untaught,
With spur and bridle undefiled,”-

his sleek coat a dun-mouse colour, with a black stripe running down his back, and with a full black mane and tail. He has a wild spiteful glance; and his eye, and his lips now and then drawn back displaying his teeth, indicate no very amiable temper. Still, we want to look at those teeth of his. Please to moderate your rancour, generous Dobbin, and let us make an inspection of their condition!

Luckily for me, I just received George Gaylord Simpson’s Horses so I can undo the brain damage such passages caused me. In all, Gosse’s book is more of a curiosity and a failed attempt to reconcile science and scripture. I do wonder, however, why more creationists have not tried his approach to fit geology into a Biblical context; most likely because it comes out being inconsistant with their beliefs. Then again, I wouldn’t say having a Tyrannosaurus rex in Eden, chomping on coconuts, lends much more credibility to the modern creationist movement.

Post Script: After reading Omphalos I turned to Errol Fuller’s Extinct Birds: Revised Edition. While beautifully illustrated and informative, it was very dry and not the sort of book easily read cover to cover, being that I only got to page 118 before having to give up. Don’t get me wrong, it’s a beautiful book, but not one that makes for riveting reading. Thus, in the wee hours of the night, I opened up a copy of Carl Zimmer’s At the Water’s Edge I had purchased the day before on campus for $2 and thus far it’s proven to be rewarding. So much to learn, so little time…





So geochronologists are really measuring God’s anger?

16 03 2007

And I thought I had seen it all. In the newest issue of Creation Matters (Volume 12, No. 1) creationist Paul G.Humber (author of Evolution Exposed) makes one of the downright vapid attempts at converting theistic evolutionists into creationists. How will Humber achieve such a conversion? Well, in case you didn’t know, radioactive rock is proof of God’s anger. In a feeble attempt to say that uranium decay into lead has occurred at starkly different rates in the past, Humble trips and falls flat with some creative scripture reading;

Is it possible that something in earth’s history greatly increased uranium decay into lead (a more traditional method for measuring the age of rock)?

The answer is yes-both scientifically and biblically! For one thing, there are a number of experiments that show change in the rate of nuclear decay. Second, consider Deuteronomy 32:22-“For a fire is kindled by My anger, and it burns to the depths of Sheol, devours the earth and its increase, and sets on fire the foundations of mountains.” This verse may point us in the direction that radioactive decay is a physical manifestation of God’s anger against evil, affecting even biological life. Prior to the Noachian flood, mankind lived much longer. His lifespan has diminished substantially since the flood. Also, even though Noah might well have had some immature dinosaurs on the ark, their nearly total extinction following the flood seems obvious. This also holds with respect to many other animals that have become extinct.

The only thing this letter is going to do is further convince its recipient how absolutely crazy creationists can be if they get creative. While Humber recognizes that the scripture he used above is poetic (I don’t know of any mountains literally catching on fire from radioactive decay), his depiction of God driving creatures to extinction via radioactive decay is specious, at best. If Humber is correct, God would have told Noah to save all the extant dinosaurs, but then God decided he didn’t want to rascally reptiles around anyhow and destroyed them by changing the rate of radioactive decay *smacks forehead*. In a way, I can understand people who cling to the idea that the Bible is without flaw and is literally true in every respect, because I understand they are attached to their faith very intensely (even though they are still wrong). What I don’t understand are creationists like Humber who go out of their way to find obscure references and attempt to attach them to pseudoscience, claiming that one supports the other (when it’s really just a rat’s nest of magical thinking).

In any case, if Humber were right then measuring radioactive decay can’t give us any dates at all, but rather a measure of how angry God is at any moment. Despite all the injustice in the world, is seems that his amount of rage is decreasing at a predictable rate that can be expressed in half-lives, although which radioactive decay rate best represents God’s anger is then opened up for debate. This is all, of course, absolutely insane and it boggles the mind as to how anyone can even conceive of such ideas (much less put them into print and disseminate them in hopes to convince “unbelievers”), but I guess you need to be able to do mental backflips when real life doesn’t fit what goes on inside your mind. Too bad for Humber that he can’t spot his own landing.





First look at Albertacertops

5 03 2007

Yesterday I posted about the newly-discovered early centrosaur, Albertaceratops. There were not any pictures at the time, but some pictures of the skull and a reconstruction have shown up today. Via the AP

Albertaceratops

It can be a bit difficult to discern the affinities of this dinosaur from this view, looking more like a compressed Triceratops skull than anything else. I would like to see a more head-on view (like in the reconstruction below) that makes clear the centrosaur lineage to which this dinosaur belongs.

Reconstruction

The reconstructions has more of the classic centrosaur look, the chief difference being the long, curved brow horns when normally there are just bumps or greatly reduced horns. Have a look at this Pachyrhinosaurus skull (a later centrosaur, image via Wikipedia) and you’ll see what I mean;

Pachyrhinosaurus skull

Obviously I haven’t seen the fossil material myself, but as always the reconstruction should be taken with a grain of salt; there’s plenty of fossil material to infer what the head of the animal likely looked like, but some “educated guesses” are still involved to fill in the gaps. Even so, this is certainly an exciting discovery, further illuminating the amazing diversity of horned dinosaurs.





New dinosaur! – Albertaceratops

4 03 2007

According to this Yahoo!News article, there’s a new evolutionary intermediate in town; Albertacertops nesmoi. For a long time, ceratopsians with a variety of horn shapes and sizes have been known, but it’s been difficult to pin down what groups gave rise to others. This newly discovered dinosaur appears to be the most basal of the centrasaurines, which would show that this group lost its horns over evolutionary time (later forms like Pachyrhinosaurus lacking large brow horns). It is curious that large horns were developed and then lost by some groups with the proliferation of the ceratopsians, some fossils that predate this new discovery by about 12 million years did have large horns as well, i.e. Zuniceratops. As more intermediates come to light it would be interesting to chart the development and loss of horns in these dinosaurs, and in a way, ceratopsians remind me of the duckbilled dinosaurs, having many different varieties of horns/crests but essentially the same body plans. In any event, this is indeed an important find. Quote Jim Kirkland about the find

Lo and behold, evolutionary theory actually works

As if there was any doubt. The abstract of the paper describing the placement of the species can be found here, the disctinctive brow-horns deemed a synapomorphy (even though this dinosaur and later ceratopsians have large horns, this dinosaur is not ancestral to Triceratops or members of other groups with similar horns), thus showing the loss of brow horns in a group that developed some other odd skull characters.





Overtaxing my brain on the first day of classes…

16 01 2007

Even though the beginning of the semester (and all the trouble it brings) came too soon this year, I was looking forward to the first day of classes and so far the one class I’ve been to has offered quite a bit of food for thought. I’ll be off to Behavioral Biology later in the evening, but early this morning I had “Soils and Water”, perhaps one of the most-dreaded mandatory classes any 704 (Ecology) student has to take during their time at Cook College. Although I’m sure some parts of it will be more exciting than others, it got me thinking about something we often take for granted when it comes to ecology; soil. Soil often contains the necessary elements and nutrients that allow plants to grow, those plants in turn feeding herbivores and carnivores as we work along the food web.

Thinking about this, something at the back of my brain started kicking, reminding me that I heard that South American soil is lower in calcium content, which is why we don’t see huge animals like elephants in present day South America. This seems to make sense, but it may very well be incorrect (I haven’t been able to find said reference, assuming it exists) and other factors may account for the size of fauna in South America. Indeed, South America used to be home to some very large animals like glyptodonts, giant ground sloths (incidentally related to sloths in the superorder Xenartha), saber-toothed cats (Smilodon populator being larger than others in its genus; most saber-toothed cats weren’t much bigger than extant big cats), and the Phorusrhacidae (“Terror Birds”). Mammoths and Paraceratherium-size creatures do seem to be absent from such ecosystems, but this may be a factor of migration or geographic isolation and does not prove anything about calcium content of the soil.

The environment of South America also must be taken into account, comprising harsh plains, mountains, and dense rainforests. As far as the mountains and jungles go creatures most likely wouldn’t grow too big as size would inhibit movement, and the current lands like that of Patagonia don’t seem like there’s enough flat land or vegetation to support a breeding population of large animals. In thinking about Patagonia, however, I realized that going even further back in time to the Cretaceous period, some of the largest dinosaurs being discovered (such as Giganotosaurus and Argentinosaurus) are coming from Argentina, so obviously there must have been enough bone-building material coming from the soil & into the plants to allow for such giant creatures to be formed. Perhaps the soils were once calcium rich but became depleted, or perhaps the connection is entirely wrong.

This also sparked the thought that it would be more difficult for mammals to attain great size, being that they must keep a constant body temperature and deal with the physical ramifications of heat distribution and loss, as well as the fact that mammal mothers nurse their young on calcium-rich milk. Spotted Hyena (Crocuta crocuta) nurse their young for longer than most other mammals because they ingest so much bone (being such efficient scavengers with bone-crushing jaws), calcium that then cannot be used to make a larger or more robust skeleton. If the males, eating just as much bone, got bigger what would happen with the Hyenas? Contrary to what may be intuitive, the females are more robust and larger than males, even having false penises and being dominant over the males, perhaps keeping them in check. Indeed, the pseudo-penis of the female is used for urination, mating, and giving birth, offering full control over who she mates with and perhaps allowing for smaller, submissive males to be the rule. It seems apparent that scavenging only makes up a small part of a Hyenas diet (despite reputation) and, according to Wikipedia, 75% of kills are made by solitary members, although they often hunt in groups and are more successful during such hunts.

All of this is blind hypothesis and I don’t expect for anyone to really take me seriously; I could be extremely wrong on all the points I’ve made. The distribution of certain bone-building minerals in the soil, however, is an interesting thing I’ll be keeping in mind in order to see if there’s any correlation with the distribution of life across the planet over the ages, perhaps making a wonderful topic for my final presentation at the end of the semester.





Jonathan Wells, the “science-stopper”

16 01 2007

Once again Gil Dodgen has cut & pasted some spurious claims from a DI fellow over at UD, this time from the ID advocate that makes my brain hurt more than any other: Jonathan Wells. This past May, when I finally decided to buckle down and see what all the hubub about Intelligent Design was about, Icons of Evolution was the first book that I read and I couldn’t believe what I saw. Although I didn’t know as much as I do now about the evolution debate, and while I agree that evolutionary science is not properly taught in public schools (or even at the college level), Wells’ claims are spurious and vapid at best; I guess that’s the best you can expect from someone who also denies that HIV causes AIDS. Add all this to the fact that he’s a Moonie and has done nothing to contribute to science since getting his degree (his graduate studies funded by his church for the expressed purpose of “destroying Darwinism”) and I wonder why anyone considers anything he has to say to be of value. In any event, here’s the latest tripe to come spilling out of his mouth, dealing with the Cambrian “explosion”:

How did it happen? We don’t have the foggiest idea how it happened. Assuming a jellyfish was the common ancestor — I don’t believe that — but how do you turn a jellyfish into a trilobite? How do you turn a jellyfish into a fish with a backbone? How do you do it? I don’t just mean taking a scalpel and rearranging the parts like you’re doing a collage in third-grade art class. We’re talking about a living animal here, that reproduces itself and makes more things like itself. How do you do it? We don’t have the foggiest idea.

To try to explain this away by saying Darwin’s theory accounts for it is a science-stopper. It’s the biggest science-stopper of modern history. It stops your inquiry right there. You have no more questions. Oh, all these animals just appeared. That’s not science.

I somehow doubt that Wells has read the relevant literature on the topic, be it the wonderful popular treatment in Gould’s Wonderful Life
or the technical rundown in Valentine’s On the Origin of Phyla. PZ posted on the topic of the Cambrian “explosion” long ago, featuring wonderful charts from the Valentine book (I don’t reproduce them on here for fear of copyright issues, but visit the Pharyngula link for one of the best visual representations of what we have prior to the Cambrian through the Burgess Shale fauna), showing that it’s not as if we have no record of animal life and then the majority of present Phyla suddenly appear in the Cambrian with no explanation. Although it is true that 90% or so of all Phyla are present in the Cambrian, this does not mean life did not exist beforehand and Phylum is a very general taxonomic category, just under Kingdom in specificity. I don’t mention this to somehow downplay the huge evolutionary leaps that occurred, but as can plainly be seen in the above quote, Wells is merely setting up one of the flimsiest straw men ever to be constructed.

Unfortunately, Gil doesn’t post or link the entire passage so I can only work with what is said, but I can only assume from what Wells said is that he can’t figure out how we could get odd and wonderful arthropods like Trilobotes (or arthopod-like animals that are still awaiting proper taxonomic placement like Anomalocaris and Opabinia from the small shelly fauna and worms of Pre-Cambrian deposits. I must say I have to agree with him that you can’t get a trilobite from a jellyfish between the Ediacaran and Cambrian, especially because the ancestors to the Arthopoda were most likely segmented worms, not Cnidarians. What do I have to go on? Take a look at this critter, named Spriggina. While it’s ancestry to Trilobites is still debated, make note that it seems to have a crescent-shaped head shield, a segmented body plan, and have chevron patterns similar to those seen in Trilobites. Hopefully more such creatures will come to light, but such forms give even more credence to the worm-arthropod transition, the Onychophora (Velvet Worms) also pointing to such a relationship. Indeed, members of the Onychophora were even present in the Cambrian (although like some of the arthopods, the exact placement of these creatures is still debated), the odd Hallucigenia being one of them and thus suggest that the transition from worm to arthopod began even before the base of the Cambrian.

After such huge academic blunders (15 minutes browsing Wikipedia would have corrected Wells’ massive mistakes), Wells then goes on to shove his footh in his mouth even further saying that evolutionists consider the Cambrian an event of spontaneous generation. I’ve never heard anyone suggest that these animals just appeared, thus stopping inquiry. Quite the contrary; the wonderful fossils coming from Chengjiang, China Cambrian sediments and Ediacaran deposits are giving us an incrimentally better picture of “life before trilobotes.” There are lots of questions that still need answering (the affinities of many Cambrian animals still in dispute), but there is only so far we can discern from the fossil material we have and more study is absolutely essential to understanding what happened during this crucial time period. Why should any scientist make claims that can neither be confirmed or denied as to what happened during the Cambrian, at worst making a fool of himself and at worst adding no new actual knowledge or understanding of what occurred? Some have tried to shoe-horn odd animals like Opabinia into existing taxa before, even altering the animals appearance to be more like an arthropod in illustration, but such ideas were long ago been thrown out and did nothing to help us better understand the Cambrian. I don’t see Wells suggesting what happened during this time. Did the creator just make the animals appear? By what means did the designer shape these animals and then deliver them into the oceans to propagate? Such questions are never answered, making Wells’ arguments not only misinformed but negative, thus showing that Wells is not courageous enough to stick his neck out and offer an alternate hypothesis. If he’s so right and evolutionists are so wrong, then why not illuminate our backward thinking by telling us how it really happened? I don’t expect such an explanation to be forthcoming, although I do expect Wells to continue to claim that evolution only needs one more nail driven into the coffin before it’s burial.