‘Frog-amander’ Fossil Fills Evolutionary Gap

Michael Skrepnick.From LiveScience By Jeanna Bryner, Senior Writer posted: 21 May 2008 01:00 pm ET>>read more.     In its Early Permian habitat in Texas, Gerobatrachus hottoni would have lived on land and water where it could lunge after insects like this mayfly Protoreisma. Credit: Michael Skrepnick.     A frog-like creature with a stubby tail once paddled through a quiet pond in what is now Texas, snapping up mayflies while keeping an ear out for bellowing mates, new fossil evidence suggests.     That was about 290 million years ago.     In 1995, the amphibian specimen was discovered in fish quarry sediments in Baylor County, Texas, though it wasn’t until recently that paleontologists inspected and described the new species. Called Gerobatrachus hottoni after its discoverer Nicholas Hotton, a paleontologist at the Smithsonian Institution, the creature represents a transitional amphibian, sporting features of both frogs and salamanders.      “This amphibian is from near to the point where frogs and salamanders first split,” said lead researcher Jason Anderson, a vertebrate paleontologist at the University of Calgary in Canada. “This is kind of an early frog-amander.”      The finding, detailed in this week’s issue of the journal Nature, supports the idea that frogs and salamanders evolved from one ancient amphibian group called temnospondyls.       Like modern salamanders, the fossil of Gerobatrachus has two fused bones in its ankle. And like modern frogs, the frog-amander sports a large ear drum, or tympanic ear, which Anderson said the ancient amphibian likely used for hearing calls from mates.     “I suspect that many of the temnospondyls have a similar sort of [tympanic ear] system,” Anderson told LiveScience. “But of course unless we were able to build a time machine and go back and listen to these guys call, we won’t know for sure.”      Rather than hopping, this amphibian likely walked on land and swam in water, with the ability to lunge after prey, Anderson said. In fact, along the evolutionary history of amphibians, frogs didn’t begin hopping until the Jurassic or Triassic period. (The most definitive hopping frog fossil is dated to the Triassic, which spans from 248 million to 206 million years ago.)      “It was found in sediments from a quiet pond with a lot of fish fossils, but I suspect it was equally comfortable on land or in water,” Anderson said.

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2 Responses to “‘Frog-amander’ Fossil Fills Evolutionary Gap”

  1. Rockstar107 Says:

    Supposedly 290 million years old, the frogamander fossil was collected in Texas a decade ago, then “rediscovered” in the National Museum of Natural History in 2004. Comparative biologist Jason Anderson of the University of Calgary led the new analysis of the fossil, claiming he recognized the “froggy slamander-y sort of look” of the fossil— now dubbed Gerobatrachus hottoni.

    The creature is said to fit a “noted gap” in the amphibian fossil record—one of those gaps the media never reports on until it’s filled! Anderson judges that the animal would have looked like a stubby-tailed salamander with froglike ears and that it “pretty convincingly settles the question [that the] frog and salamander shared origins from the same fossil group.”

    A couple of thoughts for creationists. First, although the find has been reported with typical evolutionary fanfare and certainty on the surface, that’s not to say everyone agrees with the complete analysis. For example, read what National Geographic News reported from the Field Museum’s John Bolt, a curator for fossil amphibians and reptiles:

    Bolt, the Field Museum expert, cautioned that it is difficult to say for sure whether this creature was itself a common ancestor of the two modern groups, given that there is only one known specimen of Gerobatrachus, and an incomplete one at that.
    “At this point I would say it is by no means certain that this is representative of a common ancestor to frogs and salamanders, although it might be,” Bolt said.
    Bolt also says, intriguingly, “The most astonishing thing to me about this study is that this animal is far more froglike than I would ever have expected from its age. Nothing this nonprimitive has ever been described from this age. It’s just amazing.” (Emphasis added.)

    Our second thought is that it is possible that, assuming the incomplete fossil has been interpreted accurately and truly shares frog and salamander features (and such assumptions often fail to hold true), frogs and salamanders descended from the same amphibian kind—that is, selective pressures gradually exploited the genetic variation in an original amphibian kind, resulting in the two modern groupings. If not, it is possible God created an amphibian kind with features in common with both salamanders or frogs.

    As always, though, Christians must separate the actual finding from the interpretation. There are several creation-based explanations for an incomplete fossil with salamander and frog features, but all too often, well-meaning Christians swallow the evolutionary propaganda whole, facts and worldview, without trusting God over man’s often-foolish speculation.

  2. jasontimmer Says:

    It won’t be long before creationists are taken about as seriously as flat-Earthers. I don’t understand how people can be so blind. Question, Rockstar- you’re hiking through some hilly terrain with a map. Suddenly, you come to a cliff. “That’s odd” you think, because there’s no cliff on your map. Do you go ahead and walk right off the cliff because it’s “not supposed to be there”? Or do you set your map down and find a way around the flippin’ cliff? If the text doesn’t match reality, toss the text. (read: bible)

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