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Red Hill was very different 360 million years ago during the Devonian Age. Due to the continental drift, central Pennsylvania was located on the paleocontinent Laurussia (also known as Euamerica) some 20 degrees south of the equator. The climate was sub-tropic. To the east was the Acadian Mountains which rose to over 40,000 feet (the Himalayas are a little over 20,000 feet). Note that Scotland and Greenland, at this time, was part of the same continent as North America. | ||||||||||||||
| To the west was the Catskill Sea. The area of Red Hill was part of the Catskill Delta. Rain falling on the Acadians rushed down into the delta through many wide and slow moving rivers that were prone to seasonal flooding. The gentle flooding accounts for the build up of sediment that gives Red Hill its characteristic color and allowed the preservation of fossils that intrigue us today. The rivers flowed in a northwestern direction and emptied into the inland Catskill sea. |  | ||||||||||||||
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The Devonian Age is part of the Paleozoic Era. It is commonly known as the Age of Fishes. Life on earth up to the Devonian Age was limited to the creatures of the sea. The Devonian Age saw a rapid diversification of fishes. It was dominated by reef builders and then the first jawed fish followed by the lobe-finned fish and eventually the first tetrapods. The first tetrapods marked the emergence of the first vertebrates to populate dry land. Also, the land was host to arthropods (wingless insects) and arachnids (spiders). | ||||||||||||||
Plant life also flourished during this time with the dawning of
true vascular plants that produced seeds. During the late Devonian Age,
trees were beginning to cover the landscape and forests developed. This
cut down on the erosion and provided a more hospitable environment for land
animals. The transition between fish and tetrapods has been an important focus of study in paleontology. In the 1950's, Alfred Sherwood Romer suggested that tetrapods evolved from lobe-finned fishes that, during drought, would scramble over land to find new bodies of water. Natural selection would favor those who could do it best. Fossils of lobe-finned fish showed early indications of fins turning into limbs. Ichthyostega and Acanthostega (Eastern Greenland) were half fish, half tetrapod. They were primarily aquatic animals but did have limbs instead of fins. The discovery of Elginerpeton (Scotland) revealed an animal similar to Ichthyostega but with a more robust shoulder bone that would lead one to believe this animal would be more capable of locomotion on land.
Other important finds at Red Hill include Hyneria Lindae, a huge (13 ft.) predatory fish, placoderms, ray-finned fishes, sharks, and a host of Devonian plants and terrestrial invertebrates (spiders and scorpions). | |||||||||||||||
The Red Hill excavation near Hyner, Pennsylvania, boasts the
discovery of the oldest known tetrapod in North America. The fossil remains
of Hynerpeton Bassetti (3 feet long), discovered by Dr. Ted Daeschler,
included a heavy duty shoulder bone that would allow greater mobility on
land than other known tetrapods from the Devonian Age. His discovery has
prompted a re-thinking in the paleontology world about how tetrapods evolved
and made the land their home.