My 2010 Booklist Part 2 of 3: May-August

21 08 2010

Good tidings and well-wishes!

I hope that everyone had an enjoyable summer! Having finally returned from my long but entertaining pilgrimage to an internet-bereft region of the Adirondack mountains,  I’ve managed to at long last acquire an adequate chunk of time with which to update my oft-neglected blog! Given the aforementioned lack of my primary source of electronic entertainment, I was able to engage in an obscene amount of reading during this segment of this year’s literary trimester. And so, without further ado, I hereby present the second installment of my 2010 booklist. Enjoy!

Why Size Matters: From Bacteria To Blue Whales By John Tyler Bonner

My Thoughts: At a mere 7.5 inches in height and 176 pages in length, “Why Size Matters” is, amusingly (and somewhat ‘appropriately’), one of the smallest volumes to grace my bookshelves. Bonner has done an admirable job of explaining how an organism’s size affects everything from its physiology to its ecological role to its evolutionary pathways. Of particular interest are his sections concerning how size influences one’s voice, intelligence, and longevity. While his writing style is somewhat needlessly vague on occasion, it contains a delightful exuberance along with a reverence for philosophy and literary fantasy. On the whole, “Why Size Matters” is perfect for any scientifically curious bookworm in search of a light, but informative, read.

Swimming In Stone: The Amazing Gogo Fossils Of The Kimberley By John Long

My Thoughts: It’s damnably difficult to track down good popular science books about the Devonian! So I was naturally quite excited to have found this excellent diagnosis of one of the most vital and intriguing fossil localities on the planet: the Gogo site of the Western Australian Kimberley formation, home to some of the most amazing ichthyological organisms known to science. Long is one of the paleontological community’s leading fish experts, and his passion for these creatures shines through every word of his prose. Of particular interest is one of the book’s concluding chapters in which the author defends the idea that the vast majority of significant evolutionary breakthroughs which ultimately produced the tetrapod design with which we’re intimately well-acquainted occurred millions of years before the first land-dwelling vertebrates. Additionally, while a number of non-technical science books are erroneously cited as possessing a great sense of humor, “Swimming In Stone” actually delivers in this regard, sporting several genuinely funny passages which chronicle the author’s frequently bizarre experiences throughout his career, all of which congregate to paint a wonderful image of the sacrifices and rewards familiar to those who strive to dedicate their professional lives to paleontology and it is these individuals who I believe will enjoy this exquisite volume the most.

“Frozen Earth: The Once And Future Story Of Ice Ages” By Doug Macdougall

My Thoughts: “Frozen Earth” is a book which can perhaps best be termed “uneven”. It does an absolutely impeccable job of explaining the history of ice age climatology and the field’s pioneers, yet it doesn’t always satisfactorily explain the science’s underlying concepts and evidence to a lay reader such as myself. If paleoclimatology isn’t your forte, be prepared to re-read several important passages in order to ensure comprehension. However, during those occasions wherein Macdougall succueeds in his goal of disambiguating this complex information, he does so with the grace and intrigue of a truly masterful science communicator. Additionally, “Frozen Earth” contains the finest descriptions of the Permo-Carboniferous ice age and the Snowball Earth theory/controversy that I’ve ever come across in a popular science book and its discussion regarding the adverse effects of global warming upon our environment is not to be missed by anyone who cares about the planet and its inhabitants, including ourselves. Nevertheless, in overall retrospect, I simply wish that Macdougall had dispersed his descriptive powers more uniformly.

“How To Build A Dinosaur: Extinction Doesn’t Have To Be Forever” By Jack Horner & James Gorman

My Thoughts: “How To Build A Dinosaur” is a book which has been turning heads throughout the paleo-blogosphere since its initial publication last year, and for good reason. Though many reviewers, including yours truly, initially feared that Horner and Gorman’s latest literary escapade would prove itself to be little more than a compendium of pseudoscientific twaddle, it’s turned out to be no such thing. Instead, “How To Build A Dinosaur” is a concise, comprehensive, and quite readable introduction to “evo-devo” and the fledgling science of molecular paleontology. The piece de resistance, however, is the book’s excitingly plausible central thesis. This idea maintains that given the ancestry of modern birds from small, nonavian theropods, one could theoretically  isolate the developmental routes which emerge during embryonic growth and separate the former group’s gross anatomy from the latter’s. Just like their Mesozoic forebears, all present-day birds such as chickens begin to develop long tails early in their ontogeny. However, the accumulation of subsequent mutations during the course of their evolution has resulted in the acquisition of molecules which “switch off” the maturation of this tail, reducing it to the mere stub with which poultry farmers have long-since grown familiar.  Were the precise location of these deactivation molecules unearthed, their functionality could be neutralized, resulting in a chicken with an extensive tail. Similar measures could be taken to create chickens with clawed hands, toothed mouths, and scaly bodies. Ultimately, through this ingenious technique, a little creature nearly indistinguishable from a nonavian theropod could be brought into the world. Needless to say, I’ve elected to grant this volume my fullest endorsement, such as it is. A definite must-read!

“Snakehead: A Fish Out Of Water” by Eric Jay Dolin

My Thoughts: Those turning to “Snakehead”, a book dedicated to the public frenzy surrounding the 2002 discovery of a population of namesake Chinese fish scientifically known as Channa argus lurking about a secluded Maryland pond, in search of a quick biological read are bound to be amused but ultimately disappointed, for it’s most informative commentary is instead reserved for the mainstream media and its regrettable habit of instilling undue panic throughout the populace. While this is most assuredly an issue worthy of further discussion, Dolin tends to dwell upon journalistic irresponsibility at the expense of addressing the worldwide pandemic of invasive species: although his book has an irritating tendency to reprint articles, satirical sketches, political cartoons, and panel discussions about the 2002 C. argus infestation in their entirety without regard for redundancy, its prose dedicates a mere handful of pages in the introductory and concluding chapters to examining the larger issue at hand. Still, for those in search of a light-yet-evocative summer read, “Snakehead” is a good place to start.

“Zeno And The Tortoise: How To Think Like A Philosopher” by Nicholas Fearn

My Thoughts: “Zeno And The Tortoise” purports to be an introduction to philosophy equipped with a pronounced emphasis on developing an appreciation for the thought experiments and formulas created by the discipline’s greatest minds from ancient Greece to the twenty-first century. Unfortunately, however, Fearn has here succumbed to the widespread literary pathology of poorly executing an exquisite idea. This regrettable situation is chiefly the result of his vague and often impregnable prose which manages to inhibit clarity at nearly every turn: a style whose marriage to an explanatory book concerning a subject as complex and all-encompassing as philosophy spells disaster for the novice reader. Additionally, “Zeno And The Tortoise” gives virtually no mention of any sort to eastern philosophers and thus does a great dis-service for those attempting to widen their knowledge of this magnificent field on the global level. Nevertheless, Fearn’s individual chapters often serve as an impeccable review of philosophical concepts to those who had previously encountered their individual concepts: I, for example, was able to absorb his declarations concerning relativism, rationalism, utilitarianism, falsifiability, and the limitations of reasonable doubt with comparative ease, given my prior exposure to all five notions elsewhere. The book’s greatest asset to the completely clueless reader (or partially clueless reader such as myself), however, is unquestionably its “Further Reading” section which prescribes a handful of external sources through which one might obtain additional information about each chapter’s content at length. This segment notwithstanding, “Zeno And The Tortoise” should be viewed as a study guide for dedicated students of philosophy rather than a venue through which beginners may gain exposure to its various teachings.

“Dinosaur Odyssey: Fossil Threads In The Web Of Life” by Scott D. Sampson 

My Thoughts: Despite this blog’s well-documented bias towards Cenozoic mammals, my initial fascination with the field of paleontology was, as with many of its other enthusiasts,  initially sparked by an impassioned love of dinosaurs which persists unhindered to this day. “Dinosaur Odyssey” is a book which captures the essence of this infatuation by expressing a reverence for the romanticism of these incredible beasts throughout an easygoing venture into the remarkable and frequently humbling discoveries of their study. The explanatory power of each chapter’s analysis into a plethora of such  intricate paleontological, ecological, and evolutionary topics concerning this most remarkable group as their emergence, predator/prey relationships, metabolic rates, sexual displays, and near-extinction  is rivaled only by its exuberance and ardor. Furthermore, Sampson’s concluding segment about why paleontological science matters should be considered an absolute must-read for anyone who professes to care about the discipline and its future. “Dinosaur Odyssey” is that rarest of books which I can honestly recommend to everyone ranging from those in possession of so much as a hint of interest in dinosaurian paleontology to the discipline’s seasoned veterans and practitioners.

“A Sand County Almanac And Sketches Here And There” by Aldo Leopold

My Thoughts: Last February, I reprinted Aldo Leopold’s “On A Monument To A Pigeon”: a humbling and awe-inspiring essay concerning the philosophical implications of the passenger pigeon’s (Ectopistes migratorius) infamous extinction at our hands during the late eighteenth and very early nineteenth centuries. The exquisite nature of its prose and arguments inspired me to seek out “A Sand County Almanac”: a congregation of several dozen such ecological and environmental essays which homogeneously maintain an underlying philosophy of reverence and appreciation for the natural world and our fellow inhabitants therein. Of particular intrigue are “January Thaw”, “Thinking Like A Mountain”, and “The Land Ethic” for their magnificent exemplification of this worldview. My only true criticism of “A Sand County Almanac” stems from no fault of Leopold’s but rather its posthumous publication. Due to the fact that these essays were compiled merely a year after the death of their author, they’ve been subjected to little if any editorial supervision, which enables the book’s content to grow redundant when read from cover to cover. However, this is but a microscopic blemish upon the face of a truly epic volume whose effects upon the American conservationist movement rival those of Rachel Carson’s “Silent Spring” in proportion and durability.

“The Second Bill Of Rights: FDR’s Unfinished Revolution And Why We Need It Now More Than Ever” by Cass R. Sunstein

My Thoughts: In the words of Lester Ward, “Those who denounce state intervention are the ones who most frequently and successfully invoke it. The cry of lassiez faire mainly goes up from the ones who, if really ‘let alone’, would instantly lose their wealth-absorbing power”. This most divisive of contentions is  magnificently defended by Sunstein, an eminent constitutional scholar and historian. “The Second Bill Of Rights” was the informal name bestowed upon a series of, in Sunstein’s words, “constitutive commitments” (that is, ideals protected by the day’s prevailing interpretation of the nation’s constitution rather than the document itself) designed to domestically heed FDR’s famous observation that “freedom from fear is eternally linked with freedom from want”. In other words, if America were to avoid descending into a pitifully uneven state that could easily fall prey to the likes of totalitarian forces such as those which had previously swept Hitler’s Germany and Stalin’s Russia,  Roosevelt maintained that every citizen must be guaranteed an additional set of “unalienable rights”, such as the right to adequate medical care, a decent home, and a good education among others. Sunstein also examines the international effects of this second bill and reveals beyond any doubt that those countries which incorporate its essence into their political landscape are currently far better off than its nation of origin. 

“The Making Of The Fittest: DNA And The Ultimate Forensic Record Of Evolution” By Sean B. Carroll

My Thoughts: Much ado has been made about Sean Caroll’s highly readable writing style and for good reason: in “The Making Of The Fittest”, he effortlessly guides the reader through such notoriously complex evolutionary topics as endosymbiosis, evo- devo, and gene fossilization. Furthermore, while most authors of such introductory popular science texts tend to shy away from examining their field’s most unusual constituents in the fear that their added complexity would thwart the progress of the reader’s emerging comprehension, Caroll highlights a plethora of bizarre and thoroughly engaging biological nonconformists to the delight and awe of the enthusiast and layman alike. Furthermore, in a scathing and unapologetic chapter towards the book’s conclusion that can only be described as a work of sheer brilliance, the licentious and decietful tactics of “Intelligent Design” proponents are brutally unmasked. Whether you’re an evolutionary devotee or a  curious non-expert, “The Making Of The Fittest” is sure to both enlighten and entertain.

“Why Beautiful People Have More Daughters: From Dating, Shopping, And Praying To Going To War And Becoming A Bilionaire–Two Evolutionary Psychologists Explain Why We Do What We Do” by Alan S. Miller & Satoshi Kanazawa

My Thoughts: Since it’s earliest exposure to the general public via Darwin’s “The Descent Of Man And Selection In Relation To Sex”, the field of evolutionary psychology (aka: “E.P.”) has maintained the dubious honor of arguably being the most controversial subdiscipline of any scientific domain for nearly a century and a half, having managed to simultaneously divide the general public and scientific community throughout this time.  In “Why Beautiful People Have More Daughters” Miller and Kanazawa do an impeccable job of forcing the reader to understand that E.P.’s routine political incorrectness is merely an examination of the way things are and not necessarily the way they ought to be. However, the authors are far more careless with regards to the headings given to various segments of discussion: for instance, their twin declarations that “human nature… stopped evolving 10,000 years ago” and “our brains are stuck in the stone age”, while not entirely devoid of truth, are misleading and frankly somewhat reckless. Fortunately, what Miller and Kanazawa lack in diplomacy is made up for in fairness: these men certainly aren’t shy about the limitations of evolutionary psychology despite their shared passion for the subject, and this willingness to acknowledge the young demesne’s imperfections alongside its achievements and contributions is most admirable.  

“A Confederacy Of Dunces” by John Kennedy Toole

My Thoughts: Although I don’t read fiction with the frequency of the average bibliophile, my comparatively limited exposure to the art form has nonetheless instilled within me a conviction that its most interesting characters are invariably those which the audience “loves to hate”. In this sense, I’ve yet to encounter a literary figure more captivating than “A Confederacy Of Dunces”s protagonist: one Ignatius J. Reily. While the routinely deplorable escapades of this verbose, malodorous, lackadaisical, delusional, pompous, gluttonous, discourteous, self-righteous, anachronistic, hideously clad, and morbidly obese medievalist should ideally repulse the reader,  the extravagant outlandishness with which he executes such mundane activities as job-hunting and moviegoing is positively endearing. While Reily is unquestionably the novel’s star attraction, Toole’s supporting cast is miraculously devoid of virtually any character which could be truthfully cited as “stereotypical”, and these eccentrics bounce flawlessly bounce off each other to create a beautifully unorthodox plot beneath this satirical masterpiece.

“Four Reasonable Men: Marcus Aurelius, John Stuart Mill, Ernest Renan, Henry Sidgwick” by Brand Blanshard

My Thoughts: In this delightfully original and (for the most part) brilliantly executed narrative, the reader is presented with a quartet of miniature biographies about four men whom he believes to have been “great for the same reason, the government of their lives by a quiet, habitual reasonableness.” In Blanshard’s view, reasonableness is defined as the possession of such admirable (and, as Renan often noted in a secular sense, “Christlike”) qualities as discipline, restraint, fairness, tact, open-mindedness, and respect for one’s opponents. While “Four Reasonable Men” does an impeccable job of explaining why all of its subjects deserve to be cited as possessors of these most honorable traits,  it does harbor a tendency to make relatively bold declarations concerning each man’s character and values without adequately reinforcing these contentions. Fortunately, however, the offending passages are relatively rare and fail to detract from Blanshard’s ingenious approach to enriching life and addressing the ethical concerns of the human condition itself.

“A Sea Without Fish: Life In The Ordovician Sea Of The Cincinnati Region” by David L. Meyer & Richard Arnold Davis

My Thoughts: Despite my lifelong captivation with vertebrate paleontology, I must admit that the sister science of invertebrate paleontology isn’t nearly as engaging in my view. This fact largely stems from the latter discipline’s comparative disregard for functional morphology in favor of stratigraphy: while both are highly relevant fields to each study, I simply find the former to be immeasurably more interesting. Consequently, I had essentially assumed that “A Sea Without Fish” would conform to the general trend of emphasizing the geological aspects of its spineless subjects over their physiological and ecological makeup. Thankfully, I was pleasantly surprised, for Meyer and Davis have balanced both topics seamlessly to provide a thorough and captivating analysis of the Cincinnati region’s world-famous Ordovician denizens in what is perhaps the finest example of a regional paleontology book I’ve ever come across. Of particular interest are the book’s chapters concerning mollusks, echinoderms, and arthropods.

Rest assured, loyal readers: more scientific posts are on their way!





See You In August!

23 06 2010

Good tidings and well-wishes!

I’m writing this to inform my readers that “The Theatrical Tanystropheus” will be silent for a while… just under two months to be precise.

My semi-regular summer job as a camp counselor in the Adirondack mountains will commence this Friday. Given the relative remoteness of this location, I’ll be unable to access the internet regularly, if at all, and will consequently be unable to attend to the needs of this my humble corner of the internet.

In the mean time, however,  I can confidently proclaim that my next post will be written and displayed on the 20th of August.

Until then, I hope that everyone has an awesome summer and would like to extend my most heartfelt thanks to all of my regular readers: you’re the best!

See you soon!

-Mark





Weekly Spotlight: Barylambda

19 06 2010

Good tidings and well-wishes!

Last December, as part of a week-long posting extravaganza, I lent the coverage of a “Weekly Spotlight”-style entry to the superficially hippo-like  Coryphodon sp., a pantodont of the North American and European Eocene whose appearance and, in all probability, lifestyle superficially resembled those of extant hippos. In that article, I showcased the considerable range of pantodont diversity by including the following illustration in which the semiaquatic beast is perched at the top:

Restorations of some pantodonts of the North American Paleocene. A. Coryphodon. B. Barylambda. C Titanoides primaevus. D. Caenolambda. E. Pantolambda cavirictus. E. Pantolambda bathmodon. (Courtesy of paleocene-mammals.de)

This week, the sights shall be set just a wee bit lower and, consequently, we’ll discuss the creature immediately below the aforementioned Coryphodon. Barylambda sp. (a genus which contains three known species: B. faberi, B. jackwilsoni, & B. churchilli) was an equally bizarre Paleocene beast whose form and habits were similarly analagous to a subsequent group of well-known mammals: in this case, the famed giant ground sloths of the Americas.

Once again, special thanks go to regular reader Doug for the image!

For those interested in acquiring a quick read concerning the evolution and diversity of pantodonts, please consult the link provided in the opening paragraph. With regards to the purposes of this post, however, some additional taxonomic information must be discussed. Barylambda serves as the namesake genus of the Barylambdidae family whose constituents are known for exhibiting (among others) the following characteristics:

-Robust zygomatic arches which don’t flare outward.

-Long coronoid processes.

-Relatively small heads in comparison to overall body size.

-Unfused scaphoids and centrals.

-Short phalanges… ungual phalanges fissured.

-Long and heavy tails with weight-bearing modifications.

-Enormous pelvises which similarly exhibit graviportal morphologies.

The latter pair of characters (along with the Barylambdids’ noticeably elongated skulls and overall size: the largest individuals reached 2.5 meters in length and weighed approximately 650 kg) are chiefly responsible for the hypothesis which maintains that Barylambda and its kin inhabited the niche which would later be occupied by ground sloths and chalicotheres. As in their xenarthran counterparts, barylambdids almost certainly utilized their powerfully built hindlimbs and muscular tails to enable temporary periods of bipedal locomotion, which would have allowed these beasts to browse on high vegetation in a dietary style which had theoretically remained unseen in nature since the extinction of the therizinosauridae over 10 million years earlier.

May the fossil record continue to enchant us all!





How Parasites Can Drive Ecological Relationships

18 06 2010

Good tidings and well-wishes!

As I’ve mentioned earlier, I read and thoroughly enjoyed Carl Zimmer’s excellent “Parasite Rex: Inside The Bizarre World Of Nature’s Most Dangerous Creatures” last February and have been meaning to post an article about one of the book’s most fascinating points ever since (I’ve just been procrastinating): namely, how the very life-and-death struggles between predator and prey as are often, little more than puppet shows.

More often than you might think, both parties involved are, in fact, driven by parasitic pilots.

Zimmer cites several examples of this most engaging phenomenon. However, by far the most interesting hails from the great American West.

Speaking of the wild west, this story comes with it’s own version of the good, the bad, and the ugly (though precisely who’s who is debatable as we shall see…): the curtain to the tale of the California horn snail (Cerithidea californica), the California killifish (Fundulus parvipinnis), and the various shorebirds of the Golden State’s ample coastlines.

What do these seemingly random animals have in common? A fluke by the name of Euhaplorchis californiensis.

The fluke in question.

Both the snails and the kilifish inhabit salty coastal marshes, and the latter of which naturally attract hordes of piscivorous birds as well. Avian feces inadvertently transport the eggs of E. californiensis, which serve as the primary dietary component of the California horn snail. When these eggs hatch, the flukes initially castrate the unfortunate mollusks before creating several generations of their own until, eventually, larvae (“cercariae”) burst from their initial host.

The Snail In Question

Following the 0nset of this exodus, the cercariae patrol their native salt marsh looking for killifish. Once they manage to happen upon these scaly critters, the parasites latch onto their gills and crawl ever deeper into the host’s body. Eventually, the cercariae follow a certain nerve which leads them directly into the unfortunate fish’s brain. Once there, rather than penetrating this most vital organ, these worm-like creatures merely congregate to form a thin, caviar-like layer atop it.

At this stage, the parasites must now await the consumption of their host by a predatory shorebird. Once this happens, the cercariae erupt from the fish’s stomach and flock to the fowl’s gut. In this new environment, E. californiensis steals nourishment from the new host’s digestive tract and deposits its eggs within the animal’s intestines, to be deposited whenever the bird defecates and, thus, recycling the process.

However, assuming that these parasitic organisms passively leave their lives and reproductive futures entirely up to chance would be a fatal mistake.

In an experiment conducted by ecologist Kevin Lafferty and his then-student Kimo Morris during the early nineties, the behavioral tendencies of 42 captive killifish were individually observed for days on end prior to the animals’ dissection in which the presence of E. californiensis would be confirmed or denied. According to Zimmer:

“What was hidden to the naked eye came leaping out of the data. As killifish search for prey, they alternate between hovering and darting around. But every now and then, Morris would spot a fish shimmying, jerking, flashing its belly as it swam on one side, or darting close to the surface. These might be risky things for a fish to do if a bird was scanning the water. And Morris’s vigil had revealed that fish with parasites inside them were four times more likely to shimmy, jerk, flash, and surface than their healthy counterparts. Since then, Lafferty has been working with a molecular biologist to figure out how the parasites make their hosts dance. They’ve found that the flukes can pump out powerful molecular signals, known as fibroblast growth factors, which can interfere with the growth of nerves. They could turn out to be the parasite’s Prozac[: an antidepressant drug which contains a molecule that acts as a neurotransmitter].”

(For those interested in reading an entire paper on the subject of parasitic brain manipulation in this instance, do go here!)

A Great Egret: one of the many bird species in question.

Some three weeks following Lafferty and Morris’ initial experiment, the pair decided to investigate the effects of this most curious relationship upon the local environment as a whole. Through a series of field tests, they discovered a fascinating unexpected result.

These shorebirds weren’t four times more likely to devour  infected killifish, but thirty times!

Although these flukes do take a slight physiological toll upon their avian hosts, the birds would have to exert a costly amount of energy to steer clear of infected fish (assuming they’d have any way of recognizing them); wasted energy that might prove fatal. Ergo, to these feathered beasts, the benefits of ingesting fluke-filled killifish vastly outweigh the costs.

The aforementioned fantastically large percentage thus begs a very intriguing question: “If this parasite didn’t exist, could populations of these birds survive if their food was thirty times more difficult to obtain?”

For those still unconvinced by the idea that parasites are more than mere hitchhikers and instead wield an enormous amount of influence upon their residential environments as a whole, let’s return to the horn snails for a moment. Prior to his investigations concerning the effects of E. californiensis upon killifish and birds. To once again reference “Parasite rex”:

“[These flukes] don’t quite kill their snails. In a genetic sense, the snails are indeed dead, because they can no longer reproduce. But they live on, grazing on algae to feed the flukes inside them. If the snails were truly dead, the algae they ate would be left for surviving snails to graze on. Instead, the flukes-as-snails are in direct competition with the uninfected snails…

Lafferty measured how the uninfected snails performed without parasitized snails competing with them. They grew faster, released far more eggs, and could thrive in far more crowded conditions. The results showed Lafferty that in nature, the parasites were competing so intensely that the healthy snails couldn’t reproduce fast enough to take full advantage of the salt marsh. In fact, if you were to get rid of the fluke, the snail’s overall numbers would nearly double. And this being the real world rather than a lab, that explosion would ripple out through much of the salt marsh ecosystem, thinning out the carpet of algae and making it easier for predators of snails, such as crabs, to thrive.”

If I’ve managed to pique your interest with these excerpts, I’d most heartily recommend checking out “Parasite Of The Day“: an exquisite blog run by some of the world’s leading parasitologists. If you’re anything like me, your mornings won’t be complete without it!

Cheers,

-Mark Mancini





Weekly Spotlight: Plotopterum

12 06 2010

Good tidings and well-wishes!

NOTE: Due to the scarcity of images depicting Plotopterum and its family, this post will be somewhat more “text-heavy” than usual.

Many creationists deride the paleontologist’s seemingly dubious ability to reconstruct entire organisms from solitary bones or even from fragments thereof. Granted, this practice is far from fool-proof and, consequently, the experienced student of this prehistoric study knows better than to inject an irresponsibly large amount of purely hypothetical ideas into reconstructions based on these mysterious fossils. However, what young-Earthers and other non-scientists fail to realize is that a single bone, even an incomplete one, can reveal an immense amount of information about its owner’s anatomy, lifestyle, and taxonomic relationships. A perfect example of this fact lies within the story of the plotopteridae: a family of penguin-like diving birds of the Oligocene and Miocene of Japan and North America.

In 1968, ornithologist Hildegarde Howard of the Los Angeles County Museum classified the isolated proximial end of a coracoid hailing from a mid-Tertiary deposit in the outskirts of Bakersfield. In her official scientific paper on the subject, she gave voice to her suspicion that the bone came from a pelicaniform bird such as a cormorant, gannet, booby or pelican yet was distinct enough to justify not only the creation of a new species, Plotopterum joaquinensis, but a new family as well: the Plotopteridae, the name of which literally means “the swimming winged”.

The coracoid in question.

Just what made this coracoid fragment so special as to warrant this significance in Howard’s view? In her original short communication, she writes:

“The swelling of the lower part of the triosseal canal in the fossil coracoid, the narrowness and thickness of the bone in this area and through the neck, and the anterior overhang of the head are characters found in marine birds such as the penguins and alcids. Although taxonomically unrelated, these two groups of birds are alike in the modification of the wing bones toward a flipper-like condition adapted to under water “flight.” Even in those alcids still capable of aerial flight, the coracoid has similar characters. The swelling of the lower triosseal region tends to narrow and deepen the passageway for the pectoral tendon, and presumably afforded support to the tendon so as to strengthen the upstroke of the wing in swimming. The channel is even more constricted and deeper in the alcids and penguins than in Plotopterum, suggesting that the fossil bird may not have been the equal of these other birds as a swimmer…

The modifications of the bone are entirely different from those found in the coracoid of the flightless cormorant, Nannopterum. In Nannopterum the modifying process has been one of degeneration, whereas the evidence indicates that in Plotopterum the wing had assumed a secondary function as a strong swimming organ. The fact that the modifications of the coracoid parallel those of the coracoid of penguins and auks suggests that the wing elements were shorter and more flattened in the fossil than in the cormorants and anhingas. Obviously Plotopterum represents a trend in aquatic adaptation sufficiently distinct from either of these two existing groups to warrant the designation of a separate family, to be known as the Plotopteridae.”

This conclusion was significantly less obvious to several of Howard’s colleagues. Storrs Olson, a distinguished Smithsonian ornithologist (who still resides at the institution and is considered to be one of the foremost paleo-ornithologists of our time), heavily criticized the perceived boldness of her argument and was vehemently skeptical of her decision to create an entire family on the basis of a single fossilized scrap.

However, Olson was eventually forced to concede the validity of Howard’s contentions when a near-complete bird skeleton which nearly rivaled the largest modern penguins in size was unearthed from the Oligocene of Washington in 1977 by the late, great amateur fossil collector Douglas Emlong. According to David Rains Wallace’s “Neptune’s Ark: From Ichthyosaurs To Orcas”:

“Its rigid, paddlelike wings were powerful enough to ‘fly’ through the water penguin-fashion, and its sturdy leg bones suggested that it too had waddled about on land. But it wasn’t a penguin. In fact, its wing bone turned out to be like Plotopterum‘s proving that Howard’s new family had existed, and Olson accordingly named it Tonsala hildegardae. Other skeletal aspects upheld Howard’s idea that Tonsala was a pelican and cormorant relative, although its affinities were more with freshwater anhinga, which [use] feet instead of wings for underwater propulsion. Tonsala must have been an even more efficient underwater predator than its closest living relative and, given its size, doubtless consumed vast quantities of fish, squid, and other prey.”

A reconstruction of Copepteryx, a Plotopterid from the Japanese Oligocene.

Olson has subsequently observed that the presence of these giant, penguin-like birds off the North American West Coast indicates that not only was food abundant, but that the shoreline must have contained islands upon which Plotopterum and its kin could seek refuge from any contemporaneous predatory marine mammals.

It should be noted that in addition to the  aforementioned relationship of Plotopterum and its kin to modern anhingas, Gerald Mayr has suggested that the plotopteridae may have also fact been a sister taxon to penguins as well. Regardless of the precise affiliations of this most intriguing avians, their amazing scientific history stands as a monument to what incredible academic feats the deductive reasoning of knowledgable paleontologists and anatomists can achieve.

May the fossil record continue to enchant us all!





Weekly Spotlight: Onychodus

6 06 2010

Good tidings and well-wishes!

Like many (if not most) of my fellow blogospheric paleo-nerds, I’ve long been a fan of the cultural sensation that is Ray Troll: the only paleontological (and ichthyological) artist I know of whose work can often be cited as “surreal” (how else would you describe an image like this?). Troll’s eccentric style has, in fact, inspired many of my own doodles over the years. However, another passion of this incomparable illustrator has encouraged me to elect this week’s “spotlight”: namely, his undying adoration for bizarre prehistoric fish.

And frankly, they just don’t get much weirder than the mid-to-late-Devonian lobe-fin Onychodus sp. of Germany, England, Norway, the U.S., the Middle East, the Baltic region, and, most notably, Western Australia.

Although I’m completely certain that the animal’s fantastically bizarre dentition has more than a few visitors to this humble publication thoroughly scratching their heads, this will be discussed in-depth later on (Eh, ain’t I a stinker? :) ).

Onychodus is one of the most famous residents of Western Australia’s 375-million-year-old, exquisitely preserved Devonian reef known as the Gogo formation. This paleontologically-vital site has yielded approximately 45 species of fish from essentially every major group alive at the time. As I mentioned earlier, Onychodus itself was an early sarcopterygian or “lobe-fin”, meaning that, in life, its fins were fleshy as opposed to bony and ray-like. More specifically, the (roughly) 2-to-4-meter-long beast is the namesake genus of both the Onychodontida order and Onychodontidae suborder: an exact list of distinguishing characteristics concerning both may be found here.

Onychodus reconstruction. Note that the animal was much more sinuous and eel-like in life.

In the event that anyone interested in paleo-ichthyology and the field’s Australian front in particular might wish to acquire a source of further information, I’d most heartily recommend John Long’s excellent book on the subject entitled “Swimming In Stone: The Amazing Gogo Fossils Of The Kimberley”, which dedicates an entire chapter to this marvelous fish. In it, Long writes:

Onychodus [was first described] in 1857 from isolated tooth whorls, which are sets of curved, dagger-like teeth anchored to a thin bony base. These stabbing lower-jaw teeth are the most characteristic feature of Onychodus and have enabled palaeontologists to identify it from  Middle-Late Devonian rocks in many parts of the world, including the United States, Germany, the Baltic region, the Middle East, and Australia. But the Gogo material is the only known occurrence of articulated, nearly-complete specimens. The Gogo Onchyodus skulls are so well-preserved that when we close the mouth of a reconstructed skull, the lower jaw teeth [will] actually stab through the top of the skull if they couldn’t retract into the mouth. Just as vipers have elastic ligaments that allow them to move their fangs as they open and close their mouths, so Onychodus must have been able to rotate the huge tooth whorls outwards as its mouth opened, and retract them with closure. The extensive cartilaginous jaw joints also indicate extraordinarily wide jaw movement of 120 degrees or more!”

A reconstructed fragment from an Onychodus tooth whorl.

Onychodus lower jaw reconstruction.

The conclusion that Onychodus predated upon contemporary fish, while decidedly unsurprising, has been graphically supported by a juvenile  Gogo specimen of the animal which boasts the remains of a small, unidentified placoderm tucked away in its skull. The latter creature was an estimated 30 cm in length while its attacker is believed to have stretched for  approximately 60 cm in life. Ergo, this particular Onychodus likely died as a result of attempting to swallow a victim which was half of its own size: a predicament similar to that which almost certainly befell the participants of the famed Kansan “fish-in-a-fish” skeletal pair.

Courtesy of palaeos.com

But just how did Onychodus capture its prey and, more interestingly, how did its distinctive tooth whorl come into play? To answer this most engaging question, I shall once again turn to John Long who writes:

Onychodus… [has a] retractable tooth [whorl] and a… specialized short braincase structure that allows a high degree of movement. Such features are perfectly in accord with the early specialization of an ambush-lunge predator that crunches down hard on its prey with massive stabbing teeth. Like the modern moray eels, which its skull superficially resembles, I envisage Onychodus lurking within dark crevices in the reef waiting for unsuspecting prey to pass by the opening before it darts out and grabs it, And as its mouth closes, the retractable whorls bring the struggling prey further into its huge mouth and throat cavity. Finally, with a few quick but well-timed lunges forward, the prey is swallowed whole…

[Some 2001] Onychodus material from Gogo revealed some amazing features. The sensory-like canals, which in early lobe-finned fishes are normally confined to the bones surrounding the eye, opened into the upper jaw bone on Onychodus, which would have enabled the hunter to utilize a special sensory field immediately in front of its jaws. The braincase was ossified in the front half; the rear half was largely cartilaginous. This would have been useful as a shock absorber when biting down hard. The pectoral girdle bones, which are usually tightly fitting in many primitive oteichthyans, were usually loose fitting, enabling the fish to open its jaws really wide. All these features spoke to me of one thing: predation.”

An Onychodus engaged in its theoretical hunting technique.

While Onychodus‘ cranial morphology is indubitably fascinating, the anatomy of its pectoral fin is far more significant in the evolutionary sense. Prior to the discovery of Panderichthys (and the slightly-younger but much more famous Tiktaalik), Onychodus was in fact the oldest known vertebrate of any kind to sport the basic tetrapod limb pattern of a humerus connected to a radius and ulna for quite some time. This facet of the fish’s anatomy corresponds quite nicely to the hypothesis of it being an ambush predator: such powerful forelimbs, when coupled with its muscular, serpentine post-cranial body, could have easily assisted the beast’s forward lunges while assailing its prey.

May the fossil record continue to enchant us all!





Creature’s Pet: “Lake Placid” (1999)

2 06 2010

Good tidings and well-wishes!

In light of the fact that a recent illness (don’t worry: I’m fine!) has enabled me to enjoy a bit of free time lately, I’ve decided to create a new semi-regular column here at “The Theatrical Tanystropheus”: one which honors my love of outlandish, often cheesy but usually enjoyable monster movies. Is this remotely scientific? No, but:

A) It’s fun!

B) Although I shall refrain from naming names at present, suffice it to say that yours truly is far from the sole Creature Feature fanatic roaming about the paleo-blogosphere. :)

Please note that, as a frequently overworked college student, I cannot afford to provide this series with the regularity of the “Weekly Spotlight” saga. Nevertheless, I’ll try to review at least one monster movie per month in this space.

Right then: without further dawdling, I humbly present the first installment:

“Lake Placid” (1999)

Every so often, even the most fanatical monster movie buffs have to admit that it’s nice to see a cheesy, over-the-top, sci-fi extravaganza allude to its own absurdity without degrading into a painfully ineffective cartoonish facade. “Lake Placid” is built around an unambiguously stupid plot, but at least the film acknowledges this fact while simultaneously managing to become a genuinely fun movie.

For those who have yet to see this cinematic masterpiece, the storyline is essentially as follows:

After a diver is violently bisected while studying the local American Beaver population in the backwoods of Maine, a mysterious tooth is found in his legless corpse. So naturally, a paleontologist by the name of Kelly Scott (Bridget Fonda)  is sent from the AMNH to investigate this mysterious killer. She’s begrudgingly accompanied by Sheriff Keough (Brandon Gleeson), who serves as the obligatory xenophobic, neanderthalic resident law-enforcement official,  and level-headed Fish and Game representative Jack Wells (Bill Pullman). However, the fun truly begins when Hector Cyr (Oliver Platt), a wealthy and very eccentric mythology enthusiast arrives under the conviction that the unidentified predator is, in fact, a gargantuan saltwater crocodile (Crocodylus porosus): a crazed hypothesis which just so happens to be true.

I feel obligated to point out that this is no standard-issue C. porosus, as evidenced by the following shot:

The beast is routinely estimated to be some 30 feet (9.1 meters) in length by various cast members: however, the possibility of it being some modern relative of Deinosuchus rugosus or any other gigantic prehistoric crocodylian is ruled out almost instantly when Oliver Platt’s character cites it as merely a typical saltwater crocodile, despite the fact that the thing is roughly the size of a dump truck.

(Fun Fact: In the technical sense, this colossal reptile was brought to life via a fairly convincing combination of animatronics and CGI created by none other than “Jurassic Park”s  own late, great special effects artist Stan Winston)

The question of just how on earth this thing ever ended up in an icy freshwater New England lake miles from the ocean remains unanswered, and, frankly, I’m happy with that: it’s a refreshing change to observe that scientific characters are just as initially dumbfounded as everyone else when confronted with an impossible situation for once rather than instantly and unceasingly attempting to provide some astronomically ridiculous explanation.

Perhaps  “Lake Placid”s resident scientists are incapable of solving this quandary merely because they, like the remainder of the movie’s ensemble, are positively certifiable. There isn’t a single major character in this movie whose actions and exhortations could be so much as remotely considered “normal”. Nor can any of them be accurately cited as vaguely “polite”: even BETTY WHITE (who plays the mammoth reptile’s deranged elderly caretaker) emits a series of obscenities so vulgar that common decency forbids me from listing them here (I’ll just give you all a link:) ). That fact alone should inspire a crippling urge to see the picture deep in the heart of anyone whose ever watched “The Golden Girls”.

As a paleontology student, I particularly enjoyed Bridget Fonda’s portrayal of Kelly: a shrewd, germophobic, city girl who routinely proclaims “I don’t do field work!” during the film’s opening minutes. The woman’s idea of camping appears to be largely akin to the practice of leaving the window open in one’s three-star hotel room: a sentiment which, I can say with full confidence, is homogeneously shared by the paleontological community at large. “Lake Placid” is one of those movies which makes paleontologists (amateur and professional alike) seriously wonder just what the hell film-makers think they do all day! Oh, and be sure to avoid throwing severed heads at her.

However, the most entertaining performance of the movie is unquestionably Oliver Platt’s Hector Cyr: a man who manages to stand out as a world-class lunatic even in an ensemble which would make Pee-wee’s playhouse look like an accountancy firm. Hector is a wealthy mythology professor who believes that crocodiles are sacred, god-like beasts: a conviction which drives him to travel the world and swim with  eusuchians. His attempt at comforting Sheriff Keough (off of whom he bounces hilariously and frequently) after the loss of a deputy contains one of the most laughably screwy recollections of one’s childhood dreams that I’ve ever heard in my life. While I don’t want to give anything away, it’s sufficient to say that this reminiscence involves a course of action designed to prevent a decapitated person from stumbling about through a room of fine china.

Is “Lake Placid” a great movie? Absolutely not, but this certainly is not to say that the picture is by any definition a bad one primarily because it never takes itself too seriously. Between the appreciable special effects and a continuous stream of eccentric humor, “Lake Placid” proves itself to be an enjoyable experience for anyone in search of some light summer entertainment.








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