Examining Biodiversity Metrics and the Utility of DNA Barcoding in the Northern Great Plains

Due to heavy threats to remaining global floral and faunal diversity, it is imperative we can identify species and quantify ecosystem health to find best practices for land management and conservation. The tallgrass prairies of the Northern Great Plains are one example of a heavily imperiled ecosystem. The tallgrass prairies have been reduced to less one percent of their historical extent and are facing continued loss. Genetic approaches and evolutionary theory offer insights for identifying species and assessing how biodiversity metrics may correlate with ecosystem processes. My two projects aim to address two facets imperative to conservation in the tallgrass prairie plant communities of the Prairie Coteau, a region defined by its relatively higher elevation to surrounding: 1) identification of regional flora using DNA barcodes and 2) incorporating evolutionary history (phylogenetic diversity, PD) into biodiversity assessments of plant communities. I assessed high throughput sequencing methods for DNA barcoding using four DNA regions and evaluated their success in identifying species occurring at Oak Lake Field Station at South Dakota State University. I found moderate success for species level identification and high success rates for genus and family level identifications. Including multiple loci resulted in higher success than one-locus barcodes. Phylogenetic diversity was compared to species richness by taking floristic surveys of 21 sites across the Prairie Coteau. PD only weakly correlated with species richness. Many of the sites sampled experienced lower PD than expected. My results indicate 1) DNA barcoding has potential to act as an extension service for regional plant identification, and 2) increasing species richness is not sufficient when aiming to maximize PD

Examining the Utility of DNA Barcodes for the Identification of Tallgrass Prairie Flora

PremiseThe tallgrass prairies of North America are one of the most threatened ecosystems in the world, making efficient species identification essential for understanding and managing diversity. Here, we assess DNA barcoding with high‐throughput sequencing as a method for rapid plant species identification.MethodsUsing herbarium collections representing the tallgrass prairie flora of Oak Lake Field Station, South Dakota, USA, we amplified and examined four common nuclear and plastid barcode regions (ITS, matK, psbA‐trnH, and rbcL), individually and in combination, to test their success in identifying samples to family, genus, and species levels using BLAST searches of three databases of varying size.ResultsConcatenated barcodes increased performance, although none were significantly different than single‐region barcodes. The plastid region psbA‐trnH performed significantly more poorly than the others, while barcodes containing ITS performed best. Database size significantly affected identification success at all three taxonomic levels. Confident species‐level identification ranged from 8–44% for the global database, 13–56% for the regional database, and 21–80% for the sampled species database, depending on the barcode used.DiscussionBarcoding was generally successful in identifying tallgrass prairie genera and families, but was of limited use in species‐level identifications. Database size was an important factor in successful plant identification. We discuss future directions and considerations for improving the performance of DNA barcoding in tallgrass prairies

Community-level Phylogenetic Diversity Does Not Differ Between Rare and Common Lineages Across Tallgrass Prairies in the Northern Great Plains

Niche differentiation has served as one explanation for species coexistence, and phylogenetic relatedness provides a means to approximate how ecologically similar species are to each other. To explore the contribution of rare species to community phylogenetic diversity, we sampled 21 plant communities across the Prairie Coteau ecoregion, an area of high conservation concern. We used breakpoint analysis through the iterative addition of less abundant species to the phylogenetic tree for each community to assess the contribution of rare species to community phylogenetic diversity. We also quantify the phylogenetic signal of abundance using Blomberg\u27s K statistic and calculated the phylogenetic similarity between rare and common species using a phylogenetic beta-diversity metric (Dnn). To estimate the phylogenetic structuring of these prairie communities, we calculated two common metrics that capture evolutionary relatedness at different scales (MPD and MNTD). Additionally, we examine the correlation between Faith\u27s PD, MPD, and MNTD and species richness. We found rare species do not generally contribute higher levels of phylogenetic diversity than common species. Eight communities had significant breakpoints, with only four communities having an increasing trend for the rarest species. The phylogenetic signal for abundance was low but significant in only four communities, and communities had lower phylogenetic diversity than expected from the regional species pool. Finally, the strength of the correlation between species richness and phylogenetic diversity was mixed. Our results indicate niche differentiation does not explain the persistence of rare species in tallgrass prairies, as they were more closely related than expected from random, suggesting high functional redundancy between rare and common species. This is promising for the long-term resilience of this ecosystem, but only insofar as enough species remain in the system. With ongoing biodiversity loss, it is essential that we understand the role rare species play in their communities

Using auxiliary gas power for CCS energy needs in retrofitted coal power plants

Adding post-combustion capture technology to existing coal-fired power plants is being considered as a near-term option for mitigating CO[subscript 2] emissions. To supply the thermal energy needed for CO[subscript 2] capture, much of the literature proposes thermal integration of the existing coal plant’s steam cycle with the capture process’ stripper reboiler. This paper examines the option of using an auxiliary natural gas turbine plant to meet the energetic demands of carbon capture and compression. Three different auxiliary plant technologies were compared to integration for 90% capture from an existing, 500 MW supercritical coal plant. CO[subscript 2] capture (via a monoethylamine (MEA) absorption process) and compression is simulated using Aspen Plus. Thermoflow software is used to simulate three gas plant technologies. In some circumstances, it is found that using an auxiliary natural gas turbine may make retrofits more attractive compared to using thermal integration. The most important factors affecting desirability of the auxiliary plant retrofit are the cost of natural gas, the full cost of integration, and the potential for sale of excess electricity.Research Council of Norway (Statoil (Firm: Norway)Massachusetts Institute of Technology. Carbon Sequestration Initiativ

Self-motion perception training: thresholds improve in the light but not in the dark

We investigated perceptual learning in self-motion perception. Blindfolded participants were displaced leftward or rightward by means of a motion platform and asked to indicate the direction of motion. A total of eleven participants underwent 3,360 practice trials, distributed over twelve (Experiment 1) or 6days (Experiment 2). We found no improvement in motion discrimination in both experiments. These results are surprising since perceptual learning has been demonstrated for visual, auditory, and somatosensory discrimination. Improvements in the same task were found when visual input was provided (Experiment 3). The multisensory nature of vestibular information is discussed as a possible explanation of the absence of perceptual learning in darknes

A conserved filamentous assembly underlies the structure of the meiotic chromosome axis.

The meiotic chromosome axis plays key roles in meiotic chromosome organization and recombination, yet the underlying protein components of this structure are highly diverged. Here, we show that 'axis core proteins' from budding yeast (Red1), mammals (SYCP2/SYCP3), and plants (ASY3/ASY4) are evolutionarily related and play equivalent roles in chromosome axis assembly. We first identify 'closure motifs' in each complex that recruit meiotic HORMADs, the master regulators of meiotic recombination. We next find that axis core proteins form homotetrameric (Red1) or heterotetrameric (SYCP2:SYCP3 and ASY3:ASY4) coiled-coil assemblies that further oligomerize into micron-length filaments. Thus, the meiotic chromosome axis core in fungi, mammals, and plants shares a common molecular architecture, and likely also plays conserved roles in meiotic chromosome axis assembly and recombination control

The role of large corporations in entrepreneurial ecosystems - a case study of Munich

A critical omission in research on entrepreneurial ecosystems is the role of large firms. It is claimed that they are critical actors. However, the current consensus – which suggests that their effects are entirely beneficial – is superficial. We present evidence from a case study of Munich, a city that combines an emerging ecosystem with a strong corporate sector, which indicates that the reality is much more nuanced. We confirm the resource-enriching effects of corporations. However, we also identify adverse impacts on the entrepreneurial culture that arise from their conservative and risk-avoiding mindset

Mapping entrepreneurship support organisations: An examination of the ‘cluttered landscape’ critique

Entrepreneurship support organisations (ESOs) support entrepreneurs with the provision of knowledge, resources, and training. They are a popular economic development tool for promoting entrepreneurial activity. However, the large number of ESOs has led to criticisms of oversaturation. We investigate this claim by analysing the ESOs in the entrepreneurial ecosystem in Glasgow, Scotland. We draw on publicly available documentary data to map the ESOs landscape and adopt the organisational thickness lens to analyse and interpret our findings from a holistic perspective. Although the literature largely presents ESOs as homogenous, we find a large number of heterogeneous ESOs that provide a wide range of support activities which can cater to different needs. However, they do not clearly target a specific segment of entrepreneurs which makes it difficult for the clients to differentiate between them and find the most suitable ESO. This is likely the explanation for the perception of a ‘cluttered landscape’ with too many players. Considering that entrepreneurs draw on different support providers over the course of their entrepreneurial journey, a key implication of our study is that the issue of clutter is likely to improve with greater segmentation rather than reducing the number of ESOs

A Multi-Proxy Approach to Archaeobotanical Research: Archaic and Fremont Diets, Utah

New analytical techniques in archaeobotany allow researchers to examine human plant use by developing interrelated, yet independent lines of evidence. Here we outline the results of a two-method archaeobotanical approach to investigate Archaic and Fremont Great Basin diets. We conducted both macro- and microbotanical (starch granule) analyses at nine archaeological sites located in central and southwestern Utah. Our results show that in contexts where macrobotanical remains are poorly preserved, the application of microbotanical methods can produce additional sets of information, thus improving interpretations about past human diets. In this study, macrobotanical remains represented seed-based dietary contributions, while microbotanical remains came primarily from geophytes. Results suggest largely overlapping diets for Archaic and Fremont residents of Utah