THE ACCRETION MODEL OF NEANDERTAL EVOLUTION

The Accretion model of Neandertal evolution specifies that this group of Late Pleistocene hominids evolved in partial or complete genetic isolation from the rest of humanity through the gradual accumulation of distinctive morphological traits in European populations. As they became more common, these traits also became less variable, according to those workers who developed the model. Its supporters propose that genetic drift caused this evolution, resulting from an initial small European population size and either complete isolation or drastic reduction in gene flow between this deme and contemporary human populations elsewhere. Here, we test an evolutionary model of gene flow between regions against fossil data from the European population of the Middle and Late Pleistocene. The results of the analysis clearly show that the European population was not significantly divergent from its contemporaries, even in a subset of traits chosen to show the maximum differences between Europeans and other populations. The pattern of changes, over time within Europe of the traits in this subset, does not support the Accretion model, either because the characters did not change in the manner specified by the model or because the characters did not change at all. From these data, we can conclude that special phenomena such as near-complete isolation of the European population during the Pleistocene are not required to explain the pattern of evolution in this region.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72466/1/j.0014-3820.2001.tb00667.x.pd

Stephen Lory Williams (1948-2018), In Memoriam

Obituary and biography of Stephen Lory Williams (1948-2018). Excerpts: His move in 1990 returned him to Texas Tech University, taking up positions as Collection Manager in the Museum, and Adjunct Professor in the Museum Science Program. His final professional move was made in 1995 to the Department of Museum Studies at the Strecker Museum now known as the Mayborn Museum Complex at Baylor University in Waco, Texas, where he took positions as Assistant Professor and Collections Manager. Steve retired from Baylor in 2007. Steve was present at the birth of the Society for the Preservation of Natural History Collections, serving as one of the seven founding members who met at the Buffalo Museum of Science on November 6, 1985. He was one of three members of the original Election Committee. Steve went on to hold the offices of Council Member (1987-1988), President-Elect (1988-1990), President (1990-1992), and Past-President (1992-1994). In 1999, Steve received the SPNHC President’s Award for exceptional service to the organization. Steve was an active researcher and writer, authoring 134 publications. Early in his career his publications primarily concerned mammals, much of it based on extensive field work. ... Foreshadowing Steve’s later shift to work in management and preventive conservation, in 1977 he coauthored “A guide to the management of Recent mammal collections,” which brought together for the first time the techniques and materials used in the management of these collections

Bibliography of the Published Works of Stephen L. Williams

Bibliography of the published works of Stephen Lory Williams (1948-2018)

Video capture and post-processing technique for approximating 3D projectile trajectory

In this paper we introduce a low-cost procedure and methodology for markerless projectile tracking in three-dimensional (3D) space. Understanding the 3D trajectory of an object in flight can often be essential in examining variables relating to launch and landing conditions. Many systems exist to track the 3D motion of projectiles but are often constrained by space or the type of object the system can recognize (Qualisys, Göteborg, Sweden; Vicon, Oxford, United Kingdom; Opti-Track, Corvallis, Oregon USA; Motion Analysis, Santa Rosa, California USA; Flight Scope, Orlando, Florida USA). These technologies can also be quite expensive, often costing hundreds of thousand dollars. The system presented in this paper utilizes two high-definition video cameras oriented perpendicular to each other to record the flight of an object. A postprocessing technique and subsequent geometrically based algorithm was created to determine 3D position of the object using the two videos. This procedure and methodology was validated using a gold standard motion tracking system resulting in a 4.5 ± 1.8% deviation from the gold standard

Video capture and post-processing technique for approximating 3D projectile trajectory

In this paper we introduce a low-cost procedure and methodology for markerless projectile tracking in three-dimensional (3D) space. Understanding the 3D trajectory of an object in flight can often be essential in examining variables relating to launch and landing conditions. Many systems exist to track the 3D motion of projectiles but are often constrained by space or the type of object the system can recognize (Qualisys, Göteborg, Sweden; Vicon, Oxford, United Kingdom; Opti-Track, Corvallis, Oregon USA; Motion Analysis, Santa Rosa, California USA; Flight Scope, Orlando, Florida USA). These technologies can also be quite expensive, often costing hundreds of thousand dollars. The system presented in this paper utilizes two high-definition video cameras oriented perpendicular to each other to record the flight of an object. A postprocessing technique and subsequent geometrically based algorithm was created to determine 3D position of the object using the two videos. This procedure and methodology was validated using a gold standard motion tracking system resulting in a 4.5 ± 1.8% deviation from the gold standard

West Nile Virus Vaccination Protects against Usutu Virus Disease in Mice

West Nile virus (WNV) and Usutu virus (USUV) are mosquito-borne flaviviruses that can cause neuroinvasive disease in humans. WNV and USUV circulate in both Africa and Europe and are closely related. Due to antigenic similarity, WNV-specific antibodies and USUV-specific antibodies have the potential to bind heterologous viruses; however, it is unclear whether this interaction may offer protection against infection. To investigate how prior WNV exposure would influence USUV infection, we used an attenuated WNV vaccine that contains the surface proteins of WNV in the backbone of a dengue virus 2 vaccine strain and protects against WNV disease. We hypothesized that vaccination with this attenuated WNV vaccine would protect against USUV infection. Neutralizing responses against WNV and USUV were measured in vitro using sera following vaccination. Sera from vaccinated CD-1 and Ifnar1-/- mice cross-neutralized with WNV and USUV. All mice were then subsequently challenged with an African or European USUV strain. In CD-1 mice, there was no difference in USUV titers between vaccinated and mock-vaccinated mice. However, in the Ifnar1-/- model, vaccinated mice had significantly higher survival rates and significantly lower USUV viremia compared to mock-vaccinated mice. Our results indicate that exposure to an attenuated form of WNV protects against severe USUV disease in mice and elicits a neutralizing response to both WNV and USUV. Future studies will investigate the immune mechanisms responsible for the protection against USUV infection induced by WNV vaccination, providing critical insight that will be essential for USUV and WNV vaccine development.Funding for this project was provided by NIH NIAID R21 AI53988. Support was also provided by the Virginia–Maryland College of Veterinary Medicine IRC.S

Identifying artificially deformed crania

In this paper we report on a new discriminant function for the identification of artificially deformed crania. Development of the function, based on a sample of deformed and undeformed crania from the Philippines, required visual classification of the sample into deformed and undeformed groups. Working from the observation that deformed crania display flattened frontal and occipital regions, the sample was seriated based on degree of flattening; classification was based on the results of this seriation. The discriminant function, calculated using curvature indices, required only six simple measurements: arc and chord measurements for the frontal (glabella to bregma), parietals (bregma to lambda) and occipital (lambda to opisthion). The function was designed to be conservative, in that a deformed cranium may be classified as undeformed, but the opposite should not occur. Our function classified the undeformed crania with 100% accuracy and deformed crania with 76.9% accuracy, for a total of 91.9% agreement with visual classification. In order to evaluate whether the function is applicable for samples from outside the Philippines, a double blind test was conducted with a large sample of deformed and undeformed crania from a broad geographical and temporal range. For this sample, the function agreed with visual classification in 89.7% of cases; 98.8% of undeformed crania were correctly classified, while deformed crania were identified with 73.7% accuracy. These results demonstrate the utility of the new discriminant function for the classification of artificially deformed crania from diverse contexts. Copyright © 2007 John Wiley & Sons, Ltd.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/57385/1/910_ftp.pd

Palaeoanthropology - Sahelanthropus or 'Sahelpithecus'?

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/62951/1/419581a.pd

Hybridization in parasites: consequences for adaptive evolution, pathogenesis and public health in a changing world

[No abstract available