scholarly journals Criteria for determining native distributions of biota: the case of the northern plains killifish in the Cheyenne River drainage, North America

2009 ◽  
Vol 19 (1) ◽  
pp. 88-95 ◽  
Author(s):  
Christopher W. Hoagstrom ◽  
Cari-Ann Hayer ◽  
Charles R. Berry
2018 ◽  
Vol 10 (2) ◽  
pp. 1
Author(s):  
Eric Clausen

The dearth of scientific literature in which specific erosional landform origins are determined is an example of what Thomas Kuhn considered a scientific crisis. Scientific crises arise when scientists following their discipline’s established paradigm’s rules, or doing what Kuhn calls normal science, cannot explain observed evidence. Scientific crises are resolved in one of three ways. Normal science may eventually explain the evidence and normal science returns, the unsolved problems may be identified and labeled and left for future scientists to solve, or a new paradigm may emerge with an ensuing battle over its acceptance. To succeed any new paradigm must demonstrate its ability to explain the previously unexplained evidence and also open up new research opportunities. During the 20th century’s first half regional geomorphologists abiding by their discipline’s paradigm rules unsuccessfully tried to explain origins of numerous erosional landforms, such as drainage divides and erosional escarpments. Their failures eventually caused the regional geomorphology discipline, at least that part of the discipline concerned with determining specific erosional landform origins, to almost completely disappear. A new and fundamentally different geomorphology paradigm that requires massive southeast-oriented continental ice sheet melt-water floods to have flowed across the Powder River Basin has the ability to explain specific erosional landform origins and is demonstrated here by using detailed topographic map evidence to show how large southeast-oriented floods eroded the Powder River Basin’s Belle Fourche River-Cheyenne River drainage divide segment, eroded through valleys now crossing that drainage divide segment, eroded the Powder River Basin’s Belle Fourche River valley, established Belle Fourche and Cheyenne River Powder River Basin tributary valley orientations, and eroded the north-facing Pine Ridge Escarpment. The success of this and other similar new paradigm demonstrations suggest many if not all specific erosional landform origins can be determined.


1943 ◽  
Vol 8 (3) ◽  
pp. 254-259 ◽  
Author(s):  
Frank C. Hibben

Ever since the general acceptance of the theory that Bering Strait served as the entrance of man into North America, Alaska has been suggested as the most likely area for additional discoveries adding to our knowledge of Early Man. In spite of the fact that the bulk of these discoveries has occurred in the Southwest or in the far west of the United States proper, increasing attention has been paid to northern regions. The Folsom and also the Yuma problem (or problems as the case might be) have been traced into the northern Plains regions of Saskatchewan, Canada.


2013 ◽  
Vol 127 (1) ◽  
pp. 72
Author(s):  
Alisa J. Bartos ◽  
Marsha A. Sovada ◽  
Lawrence D. Igl ◽  
Pamela J. Pietz

At nesting colonies of American White Pelicans (Pelecanus erythrorhynchos), many chicks die from siblicide, severe weather, and disease; this results in carcasses available for scavenging by conspecifics (i.e., indirect cannibalism). Indirect cannibalism has not been reported previously for this species. We describe five cases of crèche-aged American White Pelican chicks consuming or attempting to consume dead younger chicks at two nesting colonies in the northern plains of North America. Cannibalism in the American White Pelican appears to be rare and likely plays no role in the species’ population ecology or dynamics; however, it might be an important survival strategy of individual chicks when food resources are limited.


2019 ◽  
Vol 131 (9-10) ◽  
pp. 1501-1518 ◽  
Author(s):  
Aoife Blowick ◽  
Peter Haughton ◽  
Shane Tyrrell ◽  
John Holbrook ◽  
David Chew ◽  
...  

Abstract Pb isotope data from over 2400 detrital K-feldspars in >50 modern sands sampled across the Mississippi-Missouri River drainage basin of North America have been collected in order to construct the first basin-wide provenance model using geochemical signals in a framework, rather than an accessory, mineral. This study represents a critical initial step in understanding the long-term routing of framework sand grains through the Mississippi-Missouri River drainage basin. Four unique Pb isotopic groups, otherwise petrographically and geochemically indistinguishable, are identifiable. Source comparisons reveal two groups corresponding to the Archean Superior and Wyoming terranes to the north of the catchment. The remaining two Pb groups represent a mixture of Appalachian, Grenville and older Granite-Rhyolite, and Yavapai-Mazatzal sourced-grains in the east of the catchment, with noteworthy input from Cenozoic volcanic rocks along the western fringe of the catchment to tributaries west of the Mississippi River, confirming prior assertions of zircon recycling in the lower drainage basin. Tracing suites of Pb isotopic groups provide a detailed map of previously undocumented tributary mixing and reveals the importance of long-lived, naturally formed impoundments in the Upper Mississippi River, which locally sequester and release sand. Tentative proportioning of sediment contributions to the terminus of the Mississippi River from individual tributaries produces similar results to recent U-Pb zircon models, boding well for the use of framework grain based modeling of sediment fluxes. The study is the largest application of Pb-in-K-feldspar fingerprinting to date and advocates its potential as a new and necessary tool for constraining relative source contributions to sinks—which will have wide applicability—especially if combined with provenance information from detrital grains of varying resilience, within large drainage systems.


1987 ◽  
Vol 44 (3) ◽  
pp. 556-561 ◽  
Author(s):  
James E. Seeb ◽  
Lisa W. Seeb ◽  
David W. Oates ◽  
Fred M. Utter

We studied the genetic relationships and postglacial dispersal of northern pike (Esox lucius) populations in North America using allozyme data. Allelic products of up to 65 protein coding loci were examined in eight populations: five from drainages in western Canada, flowing into Hudson Bay and the Beaufort Sea; two from the Missouri River drainage, flowing into the Mississippi River; and one from the upper Mississippi River drainage, flowing into the Gulf of Mexico. Only two polymorphic loci were identified, Est-1 and Ck-1, and the average observed heterozygosity was only 0.001, much lower than that observed in most teleosts. All of the populations from the drainages in western Canada and the Missouri River were genetically identical. The Mississippi River population was unique, expressing Ck-1 (140), an allele nearly absent in all other populations, at a frequency of 0.99. Our data suggest that the Missouri River drainage, during the period when it was isolated from the Mississippi River, was the southern refugium from which northern pike radiated during deglaciation.


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