Giant Pterosaurs Flew Over Paluxy Dinosaur Tracks
Recent dinosaur findings provide glimpses into the ecology of dinosaurs, with lessons for scientific inference.
Paluxy River tracks
Older creationists may remember the flap in the 1980s over alleged human tracks with dinosaur tracks in the Paluxy River near Glen Rose, Texas. The human-like tracks were later seriously questioned to the point that most creationists have dropped them as credible evidence.* The dinosaur tracks, however, were uncontroversial. Seventy years ago, Roland T. Bird photographed and then dug up a series of 17 tracks in a sequence to prevent them from erosion due to flooding. The tracks were sent to various museums. Now, three scientists from England and America have used the available data to reconstruct the original trackway. Publishing in PLoS ONE, they used a process called photogrammetry to create a 3-D digital model that allows future researchers to study the tracks in detail.
There is still some question whether the tracks, made by a sauropod and a theropod, represent a chase sequence or a chance relationship. The authors had to interpolate some evidence because only 12 of the 17 tracks could be clearly identified from Bird’s original photographs. Some parts of the reconstruction, therefore, are less clear than other parts. The authors created a 3-D flyover of the entire trackway that is posted in the paper and by the BBC News. Science Magazine, Science Daily and Live Science reported summaries of the paper without mentioning the old human-track controversy.
Pterosaur Wonders
While describing a new pterosaur exhibit at the American Museum of Natural History, Wynne Parry, reporting for Live Science, describes some of the amazing facts of these flapping flyers. In “How Pterosaurs Ruled the Skies Above the Dinosaurs,” he notes that some were heavy giants outperforming any living flyer today:
Fossils suggest the biggest pterosaur, Quetzalcoatlus northropi, had a wingspan stretching about 33 feet (10 meters), longer than that of a small airplane. Of course, not all were giants. Of the more than 150 known species, some attained birdlike sizes, along the lines of sparrows or seagulls.
With size comes weight. Michael Habib, who studies biomechanics at the University of Southern California, has calculated that one particular group of pterosaurs may have weighed more than 661 pounds (300 kilograms), a weight they managed to consistently foist into the air and keep aloft.
Habib remarked that “Flapping flight is one of the more challenging things you can do.” Of the three vertebrate groups that employed powered flight (birds, pterosaurs and bats), pterosaurs were well designed for it. Each group had its own mechanisms, which Habib attributes to chance:
Three anatomical requirements set the stage for large size in flying animals: wing anatomy that generates a large amount of lift per unit speed, hollow bones with a high ratio of stiffness to weight, and the muscle power to launch into the air, Habib said.
“Bats have the right launch system, but they don’t have pneumatic [air-filled] bones. Birds have pneumatized bones, but they don’t have the right launch system, and they don’t have as high a lift coefficient [for their] wings,” Habib said. “Pterosaurs are the only ones by happenstance that ended up with those three things.“
This means that giraffe-sized pterosaurs like Quetzalcoatlus could leap into the air and start their engines, flying off high over the dinosaurs. Most of the pterosaurs could waddle on all fours, using their elbows as front legs.
Parry relates another remarkable fact: soft tissues have been preserved in some pterosaur fossils –
One of the exhibit’s star items provides a rare glimpse of ancient skin. A fossil found in a 150-million-year-old German rock formation contained the preserved tissue of a pterosaur wing, which allowed scientists to detect layers of skin, blood vessels, muscles and the long fibers forming a series of supports within the wing. The color of the wing membrane led researchers to dub the fossil Dark Wing, which has never before been exhibited outside of Germany….
The exhibit explains that traces of fibers found on fossils from the pterosaur Sordes pilosus, or hairy devil, suggest these animals had fuzzy coats and were likely warm blooded.
Climate Change Long Ago
Another dinosaur story in Live Science bears on a major political controversy: global warming. Katia Moskvitch reports that in the dinosaur era, carbon dioxide levels were five times higher than they are today. The new estimate is much higher than previous estimates. “The higher CO2 levels [must] have [had] significant effects on the planet’s climate, and its flora and fauna,” one researcher said. One thing is clear: if humans were contemporaries with dinosaurs, it wasn’t their fault.
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*Some think the rest of the Paluxy story remains to be told, because creationists may have been too hasty to drop the subject when some of the tracks had been misinterpreted (the fact that some locals had carved giant human tracks was only part of the controversy). Dr. Walter T. Brown makes this statement in the footnotes of his book In the Beginning: “Before 1986, many thought that dinosaur tracks and human tracks were together along the banks of the Paluxy River, near Glen Rose, Texas. Some, but not necessarily all, of the humanlike tracks were made by part of a dinosaur’s foot. The film, Footprints in Stone, and John Morris’ book, Tracking Those Incredible Dinosaurs, which popularized the man-track idea, have been withdrawn. A few creationists still claim that some of these manlike tracks were made by humans. I believe that the Paluxy tracks should be studied more and many questions satisfactorily answered before claiming human tracks are along the Paluxy River.” John Morris, in an article on ICR, stated: “Even though it would now be improper for creationists to continue to use the Paluxy data as evidence against evolution, in the light of these questions, there is still much that is not known about the tracks and continued research is in order. We stand committed to truth, and will gladly modify or abandon our previous interpretation of the Paluxy data as the facts dictate.” He provided 6 questions that should be investigated further.
The dinosaur-human track controversy from the 1980s embarrassed many creationists, because the film Footprints in Stone made such a plausible case, using primary evidence. Not only did the tracks fit a human foot perfectly with left-right stride, they continued under an undisturbed bank! It is to the credit of the creationist community that they quickly withdrew their claims when critics presented evidence that the human-like parts resided within the inner portions of theropod tracks. The claws of the three-toed theropod tracks had not been visible until a critic went looking and found them (some find that suspicious). Once creationists considered that evidence with open minds, they not only withdrew their material but discouraged fellow creationists from using it (see CMI, AIG, and ICR article by John Morris, who retracted his own book). A few creationists, notably Carl Baugh and Kent Hovind, continued asserting that the human tracks were real, but most creationists have long since distanced themselves from such claims.
This is a lesson for all scientists: the need to avoid wishful thinking, jumping to conclusions because you want them to be true. Would that evolutionists would follow that example. Critics have pointed out for decades – sometimes over a century – the flaws with Haeckel’s embryos, the horse series, the ape-to-man series, and other icons of evolution, yet prominent evolutionists continue to display them as evidence for Darwinism. We recall dinosaur hunter Phil Currie remarking in CMI’s film The Voyage that Shook the World that scientists see what they expect to see.
The Paluxy story is not dead, though. One uncontroversial aspect shouts against the evolutionary long-age view: the rapid erosion of the Paluxy tracks. Seventy years ago, when Roland Bird excavated the tracks, he had to hurry because he was “fighting against constant flooding from the river,” the PLoS ONE paper mentions. Other tracks studied by creationists in the 1980s have also disappeared since they were exposed. How credible is it that scientists would happen along these spectacular trackways right when they are being destroyed by natural causes, supposedly 110 million years after the dinosaurs made the tracks? (See also the rapid destruction of
Then there is the soft tissue preservation. Evolutionists expect us to believe that hair, skin, and delicate impressions of blood vessels, muscle tissues and skin fibers of pterosaurs were preserved for up to 220 million years. This is but one of a number of soft tissue cases reported in the secular literature in recent decades. The burden of proof should be on long-agers to show this is possible; the default explanation should be that the fossils are much, much younger than claimed.
We should point out that Paluxy was not the only site suggesting man and dinosaurs were contemporaries. Currently at AIG’s Creation Museum there is a lobby exhibit showcasing multiple lines of evidence – including artwork in temples and other human sites from different parts of the world, made centuries ago – showing dinosaurian figures. The word “dinosaur” was only coined in the 19th century. These artists most likely drew images of what they saw. In many cases, the dinosaur figures are in context with other known animals. There are also dragon legends from many parts of the world: China, Europe, and North America.
So when you add up these independent lines of evidence – soft tissue preservation, ancient accounts and artwork, and intelligent design of dinosaurs, it is reasonable to postulate that humans saw dinosaurs not that long ago. It’s the evolutionary view that should be considered dubious. They are the ones who should be embarrassed, especially those who believe with Habib that pterosaurs evolved pneumatic bones, flight muscles and launch systems “by happenstance.” If you believe happenstance produced powered flight, not just once but multiple times, we would like to offer you a free flight and resort vacation package to the beautiful Isle of Debris.