A Fluted Point from Highland Guatemala

1960 ◽  
Vol 25 (3) ◽  
pp. 412-413 ◽  
Author(s):  
Michael D. Coe

AbstractAn obsidian fluted point was found on the slope of a gorge near San Rafael, just west of Guatemala City. The point probably washed from hills on the thick beds of volcanics through which the gorge is cut. This would confirm previous beliefs that the paleo-Indian occupation of the area post-dates the volcanics. The San Rafael point resembles the fluted points from Costa Rica and Durango, Mexico, and Clovis forms from the eastern United States. Thus, paleo-Indian influences from the north into Middle America may have been of predominately eastern rather than western origins.

Author(s):  
Vivian Tang ◽  
Kevin Chao ◽  
Suzan van der Lee

ABSTRACT We report tremor or local earthquake signals that occurred during the propagation of Love and Rayleigh waves from the 2012 Mw 8.6 Sumatra earthquake in three intraplate regions: Yellowstone, central Utah, and Raton basin (Colorado). These surface waves likely also dynamically triggered seismic activity along the western boundary of the North American plate, and did not trigger seismic activity in the central and eastern United States. We report additional potential dynamic triggering in the three aforementioned intraplate regions by surface waves from 37 additional large earthquakes, recorded between 2004 and 2017. These surface waves’ transient stresses generally appear to trigger tremor in seismically, volcanically, and hydrothermally active regions, such as Yellowstone, if the waves also arrive from favorable directions. These stresses do not appear to be decisive factors for triggering local earthquakes reported for the Raton basin and central Utah, whereas, surface waves’ incidence angles do appear to be important there.


2009 ◽  
Vol 24 (5) ◽  
pp. 1173-1190 ◽  
Author(s):  
Michael E. Charles ◽  
Brian A. Colle

Abstract This paper verifies extratropical cyclones around North America and the adjacent oceans within the National Centers for Environmental Prediction (NCEP) Global Forecast System (GFS) and North American Mesoscale (NAM) models during the 2002–07 cool seasons (October–March). The analyzed cyclones in the Global Forecast System (GFS) model, North American Mesoscale (NAM) model, and the North American Regional Reanalysis (NARR) were also compared against sea level pressure (SLP) observations around extratropical cyclones. The GFS analysis of SLP was clearly superior to the NAM and NARR analyses. The analyzed cyclone pressures in the NAM improved in 2006–07 when its data assimilation was switched to the Gridpoint Statistical Interpolation (GSI). The NCEP GFS has more skillful cyclone intensity and position forecasts than the NAM over the continental United States and adjacent oceans, especially over the eastern Pacific, where the NAM has a large positive (underdeepening) bias in cyclone central pressure. For the short-term (0–60 h) forecasts, the GFS and NAM cyclone errors over the eastern Pacific are larger than the other regions to the east. There are relatively large biases in cyclone position for both models, which vary spatially around North America. The eastern Pacific has four to eight cyclone events per year on average, with errors >10 mb at hour 48 in the GFS; this number has not decreased in recent years. There has been little improvement in the 0–2-day cyclone forecasts during the past 5 yr over the eastern United States, while there has been a relatively large improvement in the cyclone pressure predictions over the eastern Pacific in the NAM.


1984 ◽  
Vol 116 (4) ◽  
pp. 487-527 ◽  
Author(s):  
J. M. Campbell

AbstractThe North American species of the genera Arpedium Erichson, and Eucnecosum Reitter are revised. Five species are recognized, the holarctic species E. brachypterum (Gravenhorst), E. tenue (LeConte) and E. brunnescens (J. Sahlberg), the transcontinental boreal species A. cribratum Fauvel and the eastern United States species A. schwarzi Fauvel.Lectotypes are designated for E. brachypterum, A. cribratum, A. angulare Fauvel (= A. cribratum), and A. schwarzi. The following new synonymy is established, Arpedium norvegicum var. sallasi Munster and Eucnecosum meybohmi Lohse (= E. tenue) and Arpedium angulare Fauvel and A. columbiense Hatch (= A. cribratum). All genera and species are described and illustrated with scanning electron photomicrographs and line drawings, four maps showing the North American distribution of each species are provided, and keys are presented to aid in the identification of all the species as well as the European species Arpedium quadrum (Gravenhorst). All available records and biological data for the species are summarized.The use of the generic name Eucnecosum Reitter is discussed and the transfer of brachypterum, tenue, and brunnescens from Arpedium to this genus by Lohse is confirmed.


1961 ◽  
Vol 93 (7) ◽  
pp. 501-502 ◽  
Author(s):  
R. J. Finnegan

There are five known North American species in the genus Hylobius; H. pales (Hbst.), H. congener Dalla Torre, H. pinicola (Couper), H. radicis Buch., and H. warreni Wood. In recent years four of these species have increased considerably in economic importance in central and eastern Canada and the eastern United States; H. pales and H. radicis attacking pines and H. pinicola and H. warreni attacking spruces and pines. H. congener occurs only in small numbers and little is known about its ecology. It is important, therefore, to be able to separate these species readily in the field.


Zootaxa ◽  
2008 ◽  
Vol 1798 (1) ◽  
pp. 1 ◽  
Author(s):  
M. S. STROTHER ◽  
C. L. STAINES

The North and Central American genus Fidia Baly 1863 (Coleoptera: Chrysomelidae) is revised. The genus is redescribed and a diagnosis separating Fidia from similar genera is provided. Twenty-four species are recognized: F. lateralis Jacoby 1882 is transferred to Xanthonia; Colaspis flavescens Sturm 1826 is a nomen nudum; F. sallei Lefèvre 1877 and F. unistriata Jacoby 1882 are synonymized with F. albovittata Lefèvre 1877; F. atra Jacoby 1882 is synonymized with F. spuria Lefèvre 1877. Twelve species are described as new- F. chapini from Mexico; F. comalensis from Mexico; F. convexicollis from Texas and Oklahoma; F. costaricensis from Costa Rica; F. delilahae from Alabama and Mississippi; F. dicelloposthe from Mexico; F. dichroma from Mexico; F. marraverpa from Mexico; F. papillata from Mexico; F. pedinops from Alabama, Florida, and Georgia; F. rileyorum from the southeastern United States; and F. xanthonioides from Mexico. Lectotypes are designated for F. albovittata Lefèvre 1877, F. cana Horn 1892, F. guatemalensis Jacoby 1879, F. lurida Lefèvre 1885, F. plagiata Lefèvre 1877, F. sallei Lefèvre 1877, F. spuria Lefèvre 1877, and F. unistriata Jacoby 1882. A key to the recognized species is presented and important taxonomic characters are illustrated. Distribution maps are provided for each species.


Author(s):  
Leo W. Buss ◽  
Philip O. Yund

Many symbiotic organisms are narrowly distributed on one or a few host species. These associations are intriguing, as they invite the development of hypotheses regarding the pattern and process of speciation and serve as laboratories for the testing of methods of phylogenetic reconstruction (Kraus, 1978; Futuyma & Slatkin, 1983; Stone & Hawks worth, 1986). The evolution of host-specificity in the sea may be expected to be severely constrained by the difficulty of achieving reproductive isolation in taxa whose gametes are freely released into the water column and/or whose larvae are potentially widely distributed (Scheltema, 1977). Yet this difficulty may well be overestimated, given the recent demonstrations of limited gamete (Pennington, 1985; Yund, in press) and larval dispersal (Knight-Jones & Moyse, 1961; Ryland, 1981; Olsen, 1985; Jackson & Coates, 1986; Grosberg, 1987). Indeed, if gamete and larval dispersal are as limited as has recently been contended (Jackson, 1986), local isolation of populations may be a routine occurence, offering repeated opportunities for speciation.


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