No description available.

Elsevier Ltd and INQUA Protocyon troglodytes was a hypercarnivorous South American canid that died out during the Late Pleistocene-early Holocene extinction, an event that eliminated most large mammals on the continent. The precise timing of these extinctions is poorly understood in South America, primarily due to a lack of radiometric dates on taxa. Of the extinct South American canids, P. troglodytes have the most extensive fossil record and widest distribution. However, the age of these specimens is based on relatively coarse association with other dated taxa or sediments. This paper describes an unpublished specimen of P. troglodytes and present the first 14C date and stable isotopes (δ13C and δ15N) for the species. This is the first taxon date for the genus and species, with an age of 17,338 ± 85 BP, and represents the youngest specimen dated by any means. The isotopes indicate that P. troglodytes was a hypercarnivore, in agreement with morphological studies, and that Equus neogeus, Hippidion principale, Stegomastodon platensis, Toxodon, and Megatherium americanum may have been part of its diet.

The analysis of dental microwear is commonly used by paleontologists and anthropologists to clarify the diets of extinct species, including herbivorous and carnivorous mammals. Currently, there are numerous methods employed to quantify dental microwear, varying in the types of microscopes used, magnifications, and the characterization of wear in both two dimensions and three dimensions. Results from dental microwear studies utilizing different methods are not directly comparable and human quantification of wear features (e.g., pits and scratches) introduces interobserver error, with higher error being produced by less experienced individuals. Dental microwear texture analysis (DMTA), which analyzes microwear features in three dimensions, alleviates some of the problems surrounding two-dimensional microwear methods by reducing observer bias. Here, we assess the accuracy and comparability within and between 2D and 3D dental microwear analyses in herbivorous and carnivorous mammals at the same magnification. Specifically, we compare observer-generated 2D microwear data from photosimulations of the identical scanned areas of DMTA in extant African bovids and carnivorans using a scanning white light confocal microscope at 100x magnification. Using this magnification, dental microwear features quantified in 2D were able to separate grazing and frugivorous bovids using scratch frequency; however, DMTA variables were better able to discriminate between disparate dietary niches in both carnivorous and herbivorous mammals. Further, results demonstrate significant interobserver differences in 2D microwear data, with the microwear index remaining the least variable between experienced observers, consistent with prior research. Overall, our results highlight the importance of reducing observer error and analyzing dental microwear in three dimensions in order to consistently interpret diets accurately.

Members of the Erycinae are small to medium-sized, semi-fossorial snakes in the family Boidae (Squamata, Serpentes) known today from Africa, southwestern Asia, India, and western North America. Erycines were the predominate snakes in faunas of North America during the Paleogene. In North America, only the minute, extinct erycine Pterygoboa is known to have additional wing-like processes situated on the postzygapophyses of the vertebrae. Here we report on Pterygoboa from one latest Oligocene (25-24 Ma) (White Springs) and two early Miocene (≈20-19 Ma) localities (Miller, Thomas Farm) in Florida. These specimens represent a significant chronological and southern geographic range extension for the genus and permit an amendment to the morphological description of this unusual snake.

South-central Florida's latest Hemphillian Palmetto Fauna includes two machairodontine felids, the lion-sized Machairodus coloradensis and a smaller, jaguar-sized species, initially referred to Megantereon hesperus based on a single, relatively incomplete mandible. This made the latter the oldest record of Megantereon, suggesting a New World origin of the genus. Subsequent workers variously accepted or rejected this identification and biogeographic scenario. Fortunately, new material, which preserves previously unknown characters, is now known for the smaller taxon. The most parsimonious results of a phylogenetic analysis using 37 cranio-mandibular characters from 13 taxa place it in the Smilodontini, like the original study; however, as the sister-taxon to Megantereon and Smilodon. Accordingly, we formally describe Rhizosmilodon fiteae gen. et sp. nov. Rhizosmilodon, Megantereon, and Smilodon (= Smilodontini) share synapomorphies relative to their sister-taxon Machairodontini: serrations smaller and restricted to canines; offset of P3 with P4 and p4 with m1; complete verticalization of mandibular symphysis; m1 shortened and robust with widest point anterior to notch; and extreme posterior "lean" to p3/p4. Rhizosmilodon has small anterior and posterior accessory cusps on p4, a relatively large lower canine, and small, non-procumbent lower incisors; all more primitive states than in Megantereon and Smilodon. The former also differs from Megantereon and Smilodon gracilis by having a very small mandibular flange. Rhizosmilodon is the oldest known member of the Smilodontini, suggesting that the tribe originated in North America. Two more derived, similar-sized species evolved in parallel during the Blancan, Megantereon hesperus and Smilodon gracilis. The former is rarer, known only from the north-central and northwestern US, and presumably dispersed into the Old World. The latter is known from the eastern and southern US, and dispersed into South America.

Warning systems for natural hazards provide notification of potential hazard events through the monitoring of natural processes. Monitoring is usually technological with a wide range of detection and notification hardware available and in use. Warning sources can be natural, informal, or official and if available time to respond is short, natural and informal warnings may be the only source of information before impact of a hazard. In recent years there has been an increasing focus on end-to-end warning systems, which focus heavily on community involvement, preparedness, and warning response actions. Response actions are usually to either evacuate or shelter in place, with the added complexity of sometimes protecting valuables. Decisions to disseminate awarning are often difficult tomake, especially if the desired response is to evacuate, because as certainty of the onset or specifics of a hazard such as location, magnitude, and intensity increases over time the time remaining to respond decreases. The delivery and content of a warning message has been heavily studied and there are a range of characteristics of effective warning messages. Warning systems are often not fully effective, so they should be considered along with a range of risk management options, especially land use planning.

No description available.

Dentaries of 6 species of Myotis from eastern North America were analyzed, using landmark-based geometric morphometrics, and were distinguished with 83.3% accuracy, although sexes were poorly discriminated using this technique. Fossils of Myotis from Bat Cave, KY, were studied in an attempt to identify these specimens to species level. Southeastern Bats and endangered Indiana Bats dominated the fossil sample, with some Eastern Small-footed Bats and endangered Gray Bats. Such results demonstrate the ability to differentiate Myotis from historic and prehistoric sites and provide a tool for researchers to understand and potentially to conserve these species.

A tooth recovered from the middle Miocene Choptank Formation (Chesapeake Group) of Maryland is identified as a new cynarctin borophagine (Canidae: Borophaginae: Cynarctina), here called Cynarctus wangi n. sp. The tooth, identified as a right upper second molar, represents the first carnivoran material reported from the Choptank Formation and part of a limited record of borophagine canids from eastern North America. As ?Cynarctus marylandica (Berry, 1938), another cynarctin borophagine from the older Calvert Formation, is known only from lower dentition, its generic affinities are uncertain. However, features of this new material are compared to features of ?C. marylandica through occlusal relationships, allowing for referral to a distinct species. Even so, the Choptank Formation material still offers two possible scenarios regarding its identification. In one, its geographic and stratigraphic provenance could imply that it belongs to ?C. marylandica. If this were correct, then the generic placement of ?C. marylandica would be correct and the taxon would be more derived than some other Cynarctus species in regard to hypocarnivory, and less derived than others. The second possibility, and the one believed to be most probable, is that a distinct cynarctin borophagine is present in the Chesapeake Group in strata younger than the type specimen of ?C. marylandica. This new borophagine canid expands the sparse fossil record of this group in northeastern North America and furthers our knowledge of the fossil record of terrestrial taxa in this region.

Cryptobranchus guildayi has been described as an extinct species of large salamander that is related closely to the modern Hellbender, Cryptobranchus alleganiensis. The validity of this extinct taxon has been questioned; thus, an expanded osteological sample of modern Hellbenders was compared to the C. guildayi fossil material. Based on our analysis of the fossil material, all morphological characters used to define C. guildayi can be observed in specimens of C. alleganiensis, or are based on misidentifications. Therefore, C. guildayi is considered to be conspecific with C. alleganiensis and taxonomically should be considered a junior synonym of the latter. The reassignment of the C. guildayi specimens to C. alleganiensis expands the prehistoric geographical range of the modern species to the Potomac River and its tributaries and also extends the age of the species into the Irvingtonian North American land mammal age.