We frequently speak of the distant past in our columns. We go on to describe what our Catskills region was like thousands, millions or even hundreds of millions of years ago. For the two of us it’s just in our nature as geologists to ponder the past. And you can do this too. Look at a globe. Find your exact longitude and latitude and then stand up. Go to your front door. Wave your arm in a complete 360-degree circle and yep, this is your very own spot on the surface of the globe. It was different a century ago. And it was a lot more different a million years ago and even more so a hundred million years ago. But there are no sedimentary rocks, here in the Catskills, that date back to those times. So, there is no fossil record that tells us of those times.
That’s not the case with the Devonian time period. Our rock sequence from this time (419 to 359 million years ago) displays what must be the finest and most complete record of the Devonian in the whole world. And it is packed full of Devonian fossils. We learn so much from fossils and they offer us images from our distant geological past. But they are not the same as time traveling into those pasts and seeing them for real. We have always longed to do just that but, alas, time travel is impossible.
That’s where artists have stepped in and sought to transport us into those distant times. Charles Knight was an early 20th century artist who made a name for himself painting ancient organisms. National geographic magazine published many of his images and both of us, as children, were very much influenced by these. He is best known for his dinosaur images, but he also spent some time painting older forms and that includes some from our Devonian. We wondered if he ever painted any local creatures, so we went searching online. Sure enough, there was one and it is gem. It was a fossil fish but not just any fish. It was a creature named Dunkleosteus. See our first illustration. It was a very different sort of fish from the modern forms we are all familiar with. It was girded in a heavy bony armor. That makes it something that is called a armored placoderm fish. It also had a powerful lower jaw but no teeth. See our second image. It is thought to have been the apex predator of the Devonian seas. A lack of teeth was not a problem. Its jawbones were razor sharp and cut like meat cleavers. It’s thought that this fish had one of the most powerful bites of all the animals that have ever lived. Our first picture shows one of them about to feed on a full-grown shark. That’s right, the largest of them are estimated to have been more than 30 feet long. John Williams’ theme music to “Jaws” should be playing right now.
Turn those 360 degrees once again; did a 30-foot-long fish once swim right through your spot, your longitude and latitude? Well – we would like to think so - but we haven’t yet found a record of any from within Catskills marine sedimentary rocks. They may well be out there and perhaps you will be the person who finds one. Take another look at our second picture. You never know, do you?
Contact the authors at randjtitus@prodigy.net. Join their facebook page” The Catskill Geologist.” Read their blogs at “thecatskillgeolist.com.”
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