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"Agates History."
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The Prehistory of the Tuxtlas
Robert Santley's The Prehistory of the Tuxtlas explores the rise and demise of complex society in the Tuxtla Mountains of southern Veracruz, Mexico. Santley synthesizes over twenty-five years of survey and excavation at the site of Matacapan and the surrounding region. He recounts the development of state-level society at Matacapan from its formative-period roots through the height of its economic and political entanglements with the great city of Teotihuacan in the Basin of Mexico to its denouement after AD 1000.
eBook
Preserving fossils in the national parks; a history
The fossil record preserved throughout the National Park Service spans more than a billion years and is documented in at least 267 park units. The discovery, collection, study, and resource management of fossils from localities which are currently within parks sometimes predate the establishment of the National Park Service and many of the parks. Public education and interpretation at parks such as Agate Fossil Beds and Tule Springs Fossil Beds national monuments and many other designated areas include information on the rich history of paleontological field work by notable paleontologists undertaken prior to the areas being preserved as national park areas. Another important historical aspect for several dozen parks involves the conservation efforts undertaken by the public and interest groups to preserve and protect these important fossil localities. The evolution of the science and methodologies in paleontology is reflected in the resource management undertaken by the National Park Service and documented in park resource management records and archives, scientific publications, and agency policy. Today the National Park Service celebrates fossils by coordinating the National Fossil Day partnership which helps to promote the scientific and educational value of fossils.
Journal Article
News from the Keweenaw: Part 3-Recent Mineral Finds in Michigan's Copper Country
Rosemeyer explores the mines and minerals of Michigan's Copper Country--Keweenaw. During the last four years, the crushing of mine dumps for road repairs and construction projects has slowed down considerably, mainly because of the large inventory of crushed rock still on hand and because of the lack of major highway or commercial construction in the Keweenaw. However, extensive logging operations, primarily in Keweenaw County, have increased the need for mine-run rock for the construction and repair of logging roads in the back woods, resulting in the slow disappearance of smaller mine dumps.
Journal Article
Phalangeal fusion in schizotheriine Chalicotheres (Mammalia, Perissodactyla)
In four genera of schizotheriine Chalicotheriidae—Moropus, Tylocephalonyx, Phyllotillon, and Ancylotherium–proximal and middle phalanges of digit II of the manus fuse to form a duplex bone. Fusion of proximal and middle phalanges of digit II of the pes also occurs in many species of these genera. Radiographic and sagittal-sectional study of the fused duplex phalanges of Moropus elatus and Tylocephalonyx skinneri shows that the joint between the two bones formed fully prior to fusion but had little movement. Fusion proceeded by external enthesial interactions at the insertion of the ligament capsule and by disruption of cortical bone with trabecular bridging along the internal part of the original articular surface. Cortical disruption is more rapid on the middle than on the proximal phalangeal component of the duplex. In M. elatus, the degrees of external and internal fusion roughly correspond, and a ventral surficial groove sometimes traces the former facet, whereas in T. skinneri external fusion is much more developed than internal fusion. Phalangeal fusion seems to have strengthened the digit against strong forces applied along the medial (radial or tibial) side of the foot.
Journal Article
A Nostalgic Look at Rock Shops, Tourist Traps, and Exploited Geological Curiosities along the Roadside
Through his postcard collection, Smith describes the history and popularity of roadside rock shops, tourist gold mines, and geological curiosities during the peak of cross-country automobile trips in the US.
Journal Article
Miocene Burrows of Extinct Bear Dogs: Indication of Early Denning Behavior of Large Mammalian Carnivores
Partial skeletons of four species of extinct carnivores have been found in their dens excavated in the floodplain of an early Miocene ephemeral braided stream at Agate Fossil Beds National Monument, Nebraska. Bear dogs (Carnivora: Amphicyonidae) were the principal occupants; their den dimensions and body size are similar to those of living wolves and hyenas. Discovery of this predator community extends the record of denning behavior of large mammalian carnivores to the early Miocene, 20 million years ago.
Journal Article
Sexual Dimorphism in Chalicotheres (Mammalia, Perissodactyla)
Graphing on probability paper of radius and tibia lengths (N = 17, 16) of Moropus from the Agate Spring Quarries, Nebraska, shows a bimodal population with approximately equal numbers in each size group. These results, along with the generally uniform morphology, suggest that a single sexually dimorphic species, Moropus elatus, is represented. Accounts of size bimodality in other chalicotheriids are consistent with widespread sexual dimorphism in species of this family, despite the fact that numbers of collected individuals in the two size groups are not equal in every case.
Journal Article
