The early Devonian period is largely considered to be a world of a diverse array of lobe-finned fish, including lungfish, coelacanths, and bony fish. Over the course of time, vertebrates made evolutionary strides with provided them with the ability to travel on land. Coelacanths developed a single boned shoulder girdle, lungfish developed paired fins, and sauripterus developed the major structures on the arm (humerus, radius, and ulna). As these developments progressed and environmental pressures
At the start of the Devonian Period, about 419.2 million years ago, our planet was undergoing major change. The union of the paleo-continents of Laurentia and Baltica (made up of what is now parts of modern day North America, northern Europe, Russia, and Greenland) occurred near the beginning of the Devonian Period and formed a supercontinent that straddled the Equator. That landmass has been called Laurussia, or Euramerica. There was a great deal of red sediment created when North America collided
The Devonian period initiating approximately 416 Mya and culminating 359 Mya represents a geologic time period, which characterizes a major part of the Paleozoic Era. Traversing between the Silurian period (444 - 416 Mya), and Carboniferous period (359 – 299 Mya) the Devonian period epitomizes substantial modifications in the world's ecology and geography. In the early Devonian period, also known as the Lochkovian, Pragian and Emsian epoch, due to substantial tectonic activity, resulted in the
Melbourne has a bedrock of Middle Paleozoic age which is included within the Devonian and Silurian periods (354-441 million years prior). These rocks are overlain in wide zones which also include much more youthful rocks, and were generally part of the Tertiary and Quaternary ages (2-65 mya). Rocks of Early Silurian (441 mya) were discovered to be the most established within the bedrock. Particular in the outcrops located in the north-east around Warrandyte (Anderson Creek Formation), and on the
Precambrian Era The Precambrian era laster 4600-541 million years ago. During this time, there were no plant life on the planet. Most of the things that were on the planet were rocks. The most common type of rock was Isua greenstone. Most rocks have been eroded away, subducted, or metamorphosed. During this time, the atmospheres and oceans were formed, plate tectonics began to build up continental masses. The air during this time was mostly made up of water vapor, carbon dioxide, and nitrogen.
Isotope anomalies across the Frasnian-Famennian extinction boundary: Implications for resolving Late Devonian mysteries Abstract The cause of the Late Devonian mass extinction near the Frasnian-Famennian boundary remains uncertain. Anomalies of stable isotope values have been observed at the Frasnian-Famennian boundary commonly, indicating the abrupt changes of environments during the crisis. These changes include marine anoxia possibly triggered by land plant evolutions, global cooling, and global
Bios101 Problem Set Three 1. (two points) A researcher is excavating a fossil bed from a Devonian reef, now fossilized in Pennsylvania. She encounters many species that are new to science. a) Which species concept would be most expedient and effective, in the process of collecting, naming, and describing what she finds? Phylogenetic species concept would be the most expedient and effective process of collecting, naming, and describing what she found. Phylogenetic relies on common ancestry
members), Mule Spring Limestone, Monola Formation (lower and upper members), and the Bonanaza King dolomite (dominantly limestone and undivided). These Cambrian rocks are followed by rock layers from the Devonian period, thus meaning that an unconformity occurred between the layers. The Devonian dolomite rock layers include the Hidden Valley dolomite and the Lost Burro Formation (cherty dolomite). These are followed by the Mississippian
distinct out groups or sister taxa to all living jawed vertebrates. Placoderms evolved from agnathan (jawless) fishes in the Silurian period, about 425 million years ago. They first appeared in the Early Silurian and diversified dramatically during the Devonian and Carboniferous periods and became extinct in Permian.
Genevieve Fault Zone (Hasenmueller and Comer 1994). During the Devonian while the New Albany Shale was being deposited, the Sangamon Arch was active causing the New Albany Shale to thin out (Hasenmueller and Comer 1994). The Media Anticline was also active during the time of deposition, this can be seen by the thinning