Amazing Fossils: What Do They Mean?
Almost every week, on continents around the world, remains of once-living creatures come to light. Here are just a few of the fascinating fossils that have been reported this month. What do they suggest about life in their day?
- Sea monsters: According to New Scientist, nine giant ichthyosaurs have been found in Nevada – now a desert. And that’s not all. Something even scarier killed them: giant squids the size of blue whales, the largest current animals on Earth. If Mark McMenamin of Holyoke College is right, the giant kraken of myth was real. Other paleontologists don’t buy his explanation, but the ichthyosaur part is undeniable; although the nine giants died in different ways, “Ancient currents seem to have aligned the skeletons,” the article said.
- Nice T. rex: The feared giant of Jurassic Park, Tyrannosaurus Rex, was bigger and faster than thought, reported PhysOrg. A team from the Field Museum of Natural History in Chicago and the Royal Veterinary College “applied cutting edge technology and computer modeling to ‘weigh’ five Tyrannosaurus rex specimens.” Old Sue could claim “I was a teenage monster.” One researcher claimed, “We estimate they grew as fast as 3,950 pounds per year (1790 kg) during the teenage period of growth, which is more than twice the previous estimate,” making it one of the largest bipeds that ever lived. Someone get word to the animators for Terra Nova.
- Pterosaur tooth tales: Based on a piece of snout and a bit of a tooth from a pterosaur, according to Live Science, a researcher from the University of Leicester has decided that “a group of the extinct, flying reptiles could reach sizes larger than previously thought.” So ugly it could be called cute (see artist’s conception in the article), Coloborhynchus capito, a rare ornithocheirid found in England, used its teeth and beak to capture fish while gliding over the water, somewhat like a pelican. Extrapolating from the exceptional tooth size, the researchers estimated a wingspan of 27 feet for the creature. By comparison, today’s largest bird, the California condor, spreads its wings up to 10 feet.
- Dinosaur Arkansas raceway: A “Huge New Dinosaur Trackway” as long as two football fields, located in Arkansas, was reported by National Geographic News. The article dates the two prints at 120 million years and identifies two species, “the eight-ton Acrocanthosaurus atokensis—one of the largest predators ever to walk Earth—and sauropods, or long-necked plant-eaters.” The prints show that the former did not have webbed feet and walked pigeon-toed with toes turned a bit inward. For 120 million years, these prints never saw the light of day, but then, the article said, “A private citizen recently found the tracks, which were possibly exposed after a rainstorm scoured away a thin layer of shale.”
- Perfect dinosaur: One of the most complete dinosaur fossils ever found was reported by New Scientist, along with a picture of the creature said to by 135 million years old. The fossil, captured in Bavarian shale, preserves 98 percent of the animal’s skeleton. “Although Chinese bird and dinosaur fossils are famed for delicate details such as their feathers, they don’t match this 72-centimetre-long theropod in terms of clarity and completeness of preservation,” the article said. No feathers are evident in this fossil of an unclassified “predatory theropod” which may be the most complete dinosaur fossil ever found. As with many dinosaur fossils, this one shows the upturned head in death throes as if suffocating when it died.
- Rafting rodents: Tiny teeth said to be from rodents at least 41 million years old have been found in Peru. According to the researchers from Case Western Reserve University, reported in PhysOrg, this means that rodents rafted like Reepicheep across the Atlantic. Why? They evolved in Africa, the team believes. But then that creates a 9-million-year gap to the next oldest new-world rodent, said to be 32 million years old. “Taken all together, the pattern contradicts the theory of a northward expansion deduced from the fossil record 20 years ago,” and pushes back the evolution of rodents in South America. The fossil ash layer was dated by the argon-argon radiometric method. “This study shows that where we’re looking for fossils has a major effect on what we think we know about mammal evolution,” one team member (Darin Croft) said, affirming that “There are still a lot of great fossils to be discovered.” He offered a prediction: “Odds are pretty low that we would push back the date for these rodents by more than a million years or two.” According to Science Daily’s coverage, the tiny tooth held in the palm of a researcher’s hand proves that the “Find Is 10 Million Years Older and Confirms Animals from Africa.”
- Rafting birds: One of the most unusual birds today is the hoatzin – a denizen of South America whose young have claws on their wings. Where did it come from? According to a new theory by a German team reported on PhysOrg, this bird’s alleged ancestors arose in Africa. Unable to fly across the ocean, they must have rafted from Africa on rafts of flotsam and jetsam. This interpretation was made necessary by evolutionary estimates of the older date of the Namibian fossil.
- More early bird feather color: Additional evidence for melanosomes in fossil bird feathers has been reported in PLoS ONE by Barden, Wogelius et al. (6: e25494. doi:10.1371/ journal.pone.0025494). It’s original material they estimated at 115 to 105 million years old. “In combination, these techniques strongly suggest that not only do the feathers contain endogenous organic material, but that both geochemical and morphological evidence supports the preservation of original eumelanic pigment residue.”
- Fossil moths in color: Coloration of a different kind has been found: the coloration of moths said to be 47 million years old, reported PhysOrg. Pigments were not preserved in the fine-grained German rock, but microscopic structural patterns allowed Maria McNamara (Yale) to reconstruct the moth’s colorful flitting in its day. It was a vivid yellow-green color, tinged in blue, similar to that of modern forester moths. The fossil was notable for having structural color over its entire body. Dr. McNamara explained more about her color-sleuthing work in a related article on the BBC News about the color on fossil beetles.
- Living fossil beetle: An aquatic beetle “still alive today and widely distributed in Eurasia” had a fossil counterpart in sediments said to be 20 million years old, reported Science Daily. What does it mean for evolutionary theory? “The Siberian fossil provides new data for the long-lasting debate among scientists about the average duration of an insect species,” the article said. Contrary to long thought estimates of species duration at 2-3 million years, this fossil shows exceptional stasis for ten times longer in the evolutionary timeline. “The long-living species had to survive the massive changes of the Earth’s climate during the last millions of years — how they managed to do so is another question for scientists to address.”
What is a fossil? The definition gets a little fuzzy at the edges. Is fuzz from a hypothetical living creature evidence of its existence? Live Science entertained claims from some Russians that “indisputable proof” that the abominable snowman has been found. What is the evidence? “a few strands of hair and some tracks in the snow.” Readers can evaluate for themselves whether this supports the believers’ boast that they are “95 percent sure that the yeti exists.” Previous claims of indisputable proof have been withdrawn. It’s hard to prove a universal negative that creatures like Yeti and Bigfoot don’t exist, but like reporter Benjamin Radford said, “If populations of yetis — like Bigfoot — really exist, they have somehow managed to avoid leaving any physical traces of their presence: no bodies, bones, teeth, hair, scat, or anything else.” The irony of this statement was apparently lost on Radford (deputy editor of Skeptical Inquirer) who did not make a similar claim for SETI, which, despite the rhyme with Yeti, gets a pass among scientists in spite of similar lack of evidence.
Fossils are fascinating for everyone – creationists and evolutionists alike. Creationists have to do some extra work to scour off the hard evolutionary crust on the story that sticks, like hardened barbecue drippings, on the underlying empirical evidence. Is said fossil 135 million years old? No. It is a few days old, or weeks, or months, or years. It’s as old as when it was pulled up out of the ground. Whatever else is being claimed about it is inference. Inference requires an interpretive context. For most secular scientists, that context is Darwinian evolution and the geologic column with its millions and billions of years. That’s how they can look at a fossil beetle that is identical to those alive today, and say that it hasn’t evolved at all for 20 million years – three times the amount of time their theory alleges that a cow turned into a whale. That’s how they can pass the buck, believing that a species of insect should only last 2-3 million years, but finding stasis extending 20 million (in their scheme), they can call it “another question for scientists to address.” It’s how they can find original melanocyte material in rock and say it survived 115 million years. It’s how they can see bigger, better creatures no longer with us, and call it evolution.
With such extraordinary flexibility in their interpretive context, anything goes: rodents crossed the ocean with hoatzins, today’s hummingbirds evolved from gigantic reptiles, and beetles survived massive swings in climate without any evolutionary change at all. Drastic evolutionary changes exist side by side with extreme stasis (e.g., living fossils) among creatures that inhabited the same Earth, even the same habitat, through all its swings of climate and geology. They can see evidence of mass burials in flood waters (ichthyosaurs aligned by current, eye-blink rapid preservation of a dinosaur in sediment as it chokes), and say it just represents local happenstance. In terms of credulity, this makes the Yeti believers look like logicians by comparison. Remember that fossils exist in the present. Yes, fossils can shed light on past conditions, but only in terms of one’s chosen interpretive context. When reading scientific reports about fossils, always, always, look for the interpretive context; then gauge the credibility of the evidence against that context.