The GREAT WESTERN INTERIOR SEAWAY existed a long long time ago. To gain an improved perspective about this aspect of North American geologic history, adjust your way-back time clock machine to the last half of the Cretaceous Period of about 108 to 66 million years ago. The story and facts laid out in rock layers many hundreds of feet thick is there waiting for discoveries by scientists and avid fossil hunters. When a fossil is found and careful overlying sedimentary rock layers removed, it reveals animals of all sizes and shapes, marine animals that looked more plant like, lots of small clams and, of course, small fish, medium fish and huge fish. And to top it off, many types of marine reptiles were part of the food chain. To be the target prey for some of those long ago creatures would have been terrifying indeed.

The seaway and its relative shallow environments flooded North America’s central regions from the Arctic to the Gulf of Mexico. Giant fishes such as the Xiphactinus grew up to 16 feet long. They patrolled the water looking for any fish of any species that it could capture. Once inside its jaws, numerous long teeth prevented escape. This top predator would eventually move its prey down its throat swallowing it whole.

In a very unique situation, the fossil fish within a fish display has its own story. First, this Xiphactinus bit off more than it should have. Yes, it did get the prey fish swallowed. The fish it swallowed was a species named Gillicus. However, some paleontologists theorize that the swallowed fish did not die peacefully. Within the stomach of its host, it may have thrashed just enough to puncture internal organs or otherwise damage the digestive system of the big fish. The end result was that both fish died and together they sank to the bottom of the sea. Their bodies settled into soft sediment muds where they were buried fairly quickly by additional muddy sediments. Now cut off from oxygen, they were in the right place at the right time for a long process of fossilization to take place. Conditions have to be just right for any creature to be preserved by fossilization.

To make this find even more treasured, the time clock of geologic eons witnessed many rises and fallings of the land, numerous ocean water comings and goings and, in the long run, a great uplifting of the North American core due to plate tectonics of the earth’s relentless pushing and pulling of continental sized crust material. As the entire Great Western Interior Seaway disappeared for the last time and the land that was once ocean bottom became dry land thousands of feet above present day sea level, lots of weather events on the exposed land caused erosion of huge proportions. New sediments covered older sediments. And now, if we humans during modern times happen to be walking on the landscape of western Kansas and look into exposed gullies and examine embedded rock sequences exposed to the air and to our eyes, we might just see a small fragment of the bones of an animal.

These were the circumstances in which George F. Sternberg who at age 9 collected his first fossil, a complete plesiosaur, in 1892. He was fascinated by all kinds of fossils and continued to scour the Smoky Hills Chalk vicinity for many decades. In 1952, he found the telltale evidence of the fish within a fish. Today, the exhibit depicting Sternberg’s excavating his find, is one of the major attractions at the Sternberg Museum of Natural History. Sternberg passed away in 1969.

In the 1970s, administrators of the Sternberg Museum put an increasing emphasis on tourism and education of persons of all ages, including school children and university students and faculty. The museum continues to grow. Its major exhibits cover a wide range of all kinds of ancient prehistoric reptiles gathered from western Kansas. Now all is housed within a huge building erected in 1991.

Natural History Museums such as the Sternberg Museum are an excellent window into the past, a past so long in geological time tables that it is difficult to grasp but easy to understand. Past climates of our earth over geologic time frames have covered the entire range of hot to cold repeatedly and back again, from oceans rising and lowering, of glaciers engulfing entire continent sized areas and melting back to allow tropical conditions to dominate in places like the arctic and antarctic.

I encourage anyone who is traveling west to make your route pass through Hays, Kan. Stop and see. Look and learn. Ponder your short human life spans compared to vast geologic epochs.

While on the subject of long ago happenings, did you know that Iowans have collected METERORITES. The first known find was on Feb. 25, 1847, just 11 years after Iowa became a state. The place was near what we now know as Marion.

On Feb. 12, 1875, the people living in the Amana vicinity watched a dazzling fireball in the sky during the night between 10 p.m. and 11 p.m. The light from this meteor was noted as far away as Chicago, Omaha and St. Louis. A 74-pound fragment was found later. And lots of other fragments brought the total weight to more than 800 pounds.

Estherville residents watched at 5 p.m. as a meteorite made a loud roar during its atmospheric re-entry. This was on May 10, 1879. The main mass of this rock was found later in a marshy wetland and it tipped the scale at 430 pounds. Forest City had its excitement from a meteorite on May 2, 1890. Fragments of this stony invader came to 269 pounds. Mapleton area discoveries were found on June 17, 1939 by a farmer cultivating his field. It was 108 pounds. Lone Tree has its encounter with a space rock on May 1972. Alvord, in far northwest Iowa, is where discoveries of space rocks happened in 1976 and 1981. Most of the space rock is known as ordinary chondrite.

The biggest and best known encounter with a space rock is the Manson Impact Crater. This took place 74 million years ago when an estimated 1.5 mile diameter asteroid traveling at 70,000 miles per hour hit the edge of shallow ocean water (part of the Great Western Interior Seaway) in what is now Iowa. The impact had the energy of 10 thousand-million-million kilotons of TNT. It left a crater 23 miles in diameter and 5 miles deep. It threw bedrock materials ultimately to the far reaches of earth. Any ancient animals living at the time within central parts of what is now the United States, were killed. The blast vaporized the entire asteroid. The Manson crater is the 15th largest on earth. All of its uprooted and messed up bedrock fragments lie buried under 100 to 300 feet of glacial till. There is no above ground evidence at all of this crater. However, geologists have found evidence via sounding instruments and water well digging log data to know it is there.

The moon is full of impact craters large and small. You can see them with binoculars or telescopes. There is no atmosphere and thus no weather events to erode them. The earth, by contrast, must also be full of impact craters. Most are long gone, erased from view by many tectonics events, by glacial systems bulldozing them into oblivion and by natural weather events that erode them. But a few remnants do remain of impact craters such as the one near Winslow, Ariz., one of the best known. There are others. Check out any university geology department collection and you will learn a lot more about rocks not of earth origin.

Back on earth and to things to do, remember if you are an Izaak Walton League member to attend the Wild Game Feed at 6 p.m. on Feb. 12 at the Conservation Center at the Grimes Farm. A program afterwards will be presented by Mike Stegmann on all things pertaining to conservation board programs and projects.

Tax time means that as we do our duties of calculating Iowa income taxes, do remember the Chickadee Checkoff option. Do make a generous donation to assist with non-game wildlife conservation projects. Past involvement with Trumpeter Swans is just one example of success stories because of contributions from Iowans. Thank you in advance.

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Garry Brandenburg is a graduate of Iowa State University with BS degree in Fish & Wildlife Biology. He is the retired director of the Marshall County Conservation Board. Contact him at PO Box 96, Albion, IA 50005.