An Improved Approximate-Bayesian Model-choice Method for Estimating Shared Evolutionary History

To understand biological diversification, it is important to account for large-scale processes that affect the evolutionary history of groups of co-distributed populations of organisms. Such events predict temporally clustered divergences times, a pattern that can be estimated using genetic data from co-distributed species. I introduce a new approximate-Bayesian method for comparative phylogeographical model-choice that estimates the temporal distribution of divergences across taxa from multi-locus DNA sequence data. The model is an extension of that implemented in msBayes. By reparameterizing the model, introducing more flexible priors on demographic and divergence-time parameters, and implementing a non-parametric Dirichlet-process prior over divergence models, I improved the robustness, accuracy, and power of the method for estimating shared evolutionary history across taxa. The results demonstrate the improved performance of the new method is due to (1) more appropriate priors on divergence-time and demographic parameters that avoid prohibitively small marginal likelihoods for models with more divergence events, and (2) the Dirichlet-process providing a flexible prior on divergence histories that does not strongly disfavor models with intermediate numbers of divergence events. The new method yields more robust estimates of posterior uncertainty, and thus greatly reduces the tendency to incorrectly estimate models of shared evolutionary history with strong support.Comment: 48 pages, 8 figures, 4 tables, 35 pages of supporting information with 1 supporting table and 33 supporting figure

The influence of forest regrowth, original canopy cover and tree size on saproxylic beetles associated with old oaks

Abandoned management has caused many sites with free-standing, large oaks (Quercus robur) to become more shaded. This study shows how forest regrowth affects beetle species associated with old oaks in south-eastern Sweden. Beetles were trapped by pitfall traps placed in hollows and window traps placed near hollows in oak trunks in pasture woodlands. We assessed the influence of forest regrowth, tree size and original canopy cover on the species richness of saproxylic beetles (a total of 120 species identified) and the occurrence of 68 saproxylic beetle species in particular. Species richness was greatest in stands with large, free-standing trees. Large girth as well as low canopy cover increased frequency of occurrence for several species. Forest regrowth was found to be detrimental for many beetle species. As most localities with endangered beetles living in old oaks are small and isolated, ongoing management and the restoration of abandoned pasture woodlands should have a high priority in nature conservation

Oral History Transcript - Angela Oaks

https://scholarworks.utrgv.edu/spanishlandgrantsoralhistories/1036/thumbnail.jp

Life History and Outbreaks of an Oak Leafroller, Archips Semiferanus (Lepidoptera: Tortricidae), in Michigan

In the late 1960\u27s an outbreak of yellow-green tortricid larvae occurred over hundreds of thousands of acres of red oaks in northeastern Lower Michigan. At first the insect was thought to be the fruit tree leafroller, Archips argyrospilus (Walker); adult specimens, however, were identified by Freeman as A. serniferanus Walker. On forest lands oak or pine was the preferred cover type. In urban areas, the problem was acute where red oaks were the predominant shade tree. In 1969 and 1970 I observed this insect to learn about its life history, habits, and distribution. Besides regular field collections, some cage studies and laboratory rearings were done

Buprestidae, Cerambycidae, and Scolytidae Associated with Successive Stages of \u3ci\u3eAgrilus Bilineatus\u3c/i\u3e (Coleoptera: Buprestidae) Infestation of Oaks in Wisconsin

The species of Buprestidae, Cerambycidae, and Scolytidae found in association with Agrilus bilineatus (Weber) in declining oaks, Quercus spp., in Wisconsin, were Chrysobothris femorata (Olivier) and Dicerca sp. (Buprestidae); Amniscus macula (Say),Cyrtaphorus verrucosus (Olivier), Euderces picipes (Fabricius), Graphisurus fasciatus (DeGeer), Neodytus acuminatus (Fabricius), Sarosesthes fulminans (Fabricius), and Xylotrechus colonus (Fabricius) (Cerambycidae); and Monarthrum fasciatum (Say), Monarthrum mali (Fitch), Pseudopityophthorus minutissimus (Zimmerman), and Xylaterinus politus (Say) (Scolytidae). In general, weakened oaks were first attacked by A. bilineatus. and at times that same year by C. femorata. G. fasdalus, and P. minutissimus. Infestation by M.fasciatum, M. mali, and X. politus began the season following first attack by A. bilineatus. With the exception of A. bilineatus, the above mentioned Buprestidae and Cerambycidae appeared to preferentially infest dead wood, often those portions that had died the previous season

Oaks retained in production spruce forests help maintain saproxylic beetle diversity in southern Scandinavian landscapes

In Northern Europe, human activities have caused a substantial decrease in the number of old deciduous trees over the last two centuries, leading to a decline in species populations associated with this habitat. One way to mitigate this trend is to increase the abundance of mature and old deciduous trees in commercial forests, such as by tree retention at final harvest. We analysed the biodiversity value of retained mature oaks in the production forests of Norway spruce in southern Sweden, using oaks in pastures as reference. The forest oaks were grown in two different levels of shade. We analysed two categories of saproxylic (i.e. dead wood-dependent) beetles: those utilizing oaks (Group I) and those utilizing oak but not spruce (Group II, which was, therefore, a subcategory of Group I). We found that forest oaks sustained high beetle diversity, in particular, Group I beetles, which were significantly more abundant in forest oaks in heavily thinned patches, as compared with pasture oaks and oaks in moderately thinned patches. For both beetle groups, the composition differed between the forest oaks and pasture oaks, indicating that the forest oaks can be a complementary habitat to that of pasture oaks. There was a positive relationship between oak dead branch diameter and beetle biodiversity, but only for older oaks (∼200 years old). We conclude that retaining oaks in production spruce forests can increase the diversity of oak-associated beetles at the landscape scale. Since many oak associated species depend on relatively high levels of insolation, management of retained oaks in production forests should include periodic removal of encroaching trees

A Note on Effects of Sewage Effluent Irrigation on Specific Gravity and Growth Rate of White and Red Oaks

A 2.5-acre forested terrace of mixed hardwoods (predominately oak) in southern Missouri was sprinkler-irrigated with treated sewage effluent. Ninety-two oak trees were sampled (increment cores) at breast height. There were 41 white oaks and 52 red oaks. Growth rate increased significantly for white oaks and specific gravity increased significantly for red oaks

The Battle Oaks: Preserving a Living Legend

Values at Work Series: Facilities Services developed our core values of Service, Integrity, Teamwork, Excellence, and Stewardship (collectively referred to as SITES) based on the way we approach our work. Our values can be found throughout our areas of services in many ways.Through a series of articles, the Values at Work Series is devoted to providing a closer look at how our values are hard at work. Each article focuses on an area of service and how that group incorporates our values in a significant way. We are proud of our employees who continue to serve as an example of “walking the talk” every day.The Battle Oaks are among The University of Texas at Austin’s oldest living trees on campus at upwards of 250-300 years old. These three Texas live oaks graced the grounds of the original Forty Acres when the university opened in September 1883.Facilities Service