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Habitat degradation can have significant effects on native species inhabiting natural ecosystems. Within oak barrens and oak-pine barrens ecosystems, there is a complex interspecies interaction between the federally endangered Karner blue butterfly (Lycaeides melissa samuelis) and its obligate host plant, wild lupine (Lupinus perennis L.). Recruitment of wild lupine is critical for maintaining butterfly populations; however, this recruitment can be impeded by habitat fragmentation. Reduced recruitment can result in low genetic diversity in isolated populations, limiting its adaptive potential to respond to environmental change. This study was aimed at understanding the genetic diversity and population structure of wild lupine populations throughout central and west Michigan. We identified significant population structure across most of the populations sampled, with only two sites not significantly different from each other. No sites within our study area displayed statistically significant levels of inbreeding. There are also at least two genetic clusters of wild lupine present within our study region, although there is significant overlap among these groups, indicating that genetic differentiation among clusters may be limited. Key words: wild lupine, Lupinus perennis, population structure, population management, Introduction Complex species interactions are a major driving force influencing ecosystem dynamics across the globe. While much research has focused on understanding how ecosystems and the species inhabiting them respond [...]

When cyanobacterial phytoplankton form harmful cyanobacterial blooms (HCBs), the toxins they produce threaten freshwater ecosystems. Hydrogen peroxide is often used to control HCBs, but it is broadly toxic and dangerous to handle. Previously, we demonstrated that glucose addition to lake water could suppress the abundance of cyanobacteria. In this study, glucose was compared to hydrogen peroxide for the treatment of cyanobacterial phytoplankton communities. The six-week study was conducted in the large mesocosms facility at Grand Valley State University's Annis Water Resources Institute in Michigan. To 1000 L of Muskegon Lake water, glucose was added at either 150 mg or 30 mg glucose/L. Hydrogen peroxide was added at 3 mg/L to two 1000 L mesocosms. And two mesocosms were left untreated as controls. Triplicate 100 mL samples were collected weekly from each mesocosm, which were then filtered and frozen at −80 °C for 16S rRNA amplicon sequencing. The 16S rRNA amplicon sequencing results revealed that hydrogen peroxide treatment quickly reduced the relative abundance of the cyanobacteria compared to the control mesocosms, but the cyanobacteria population returned over the course of the 6-week study. On the other hand, both glucose concentrations caused a rapid proliferation of multiple low abundance proteobacterial and bacteroidotal taxa resulting in notable increases in taxonomic richness over the duration of the study and reducing the relative abundance of cyanobacteria. Although hydrogen peroxide quickly suppressed the cyanobacteria, the population later returned to near starting levels. The glucose suppressed the cyanobacterial phytoplankton apparently by promoting competitive heterotrophic bacteria. [ABSTRACT FROM AUTHOR]

Reproductive efforts are energetically costly and often result in significant trade-offs with other metabolic processes. In many animals, androgens influence how this energy is allocated during the breeding period. In this study, androgen levels of parental bluegill sunfish (Lepomis macrochirus Rafinesque, 1819) were manipulated by implanting males with either 11ketotestosterone (11-KT) or flutamide (an androgen receptor antagonist) shortly after spawning. Parental behaviours were assessed for 3 days after implantation. Differential brain gene expression between the two groups was examined using a 44 000 microarray gene chip. We found that 11-KT-implanted males exhibited lower levels of expression of genes related to immune function compared with flutamide-implanted males, suggesting that high androgen levels negatively affect the male immune system. These data thus indicate that a significant trade-off may exist between maintaining high levels of androgens and decreased immune function in parental male bluegill. Key words: immune function, androgens, parental care, gene expression, bluegill sunfish, Lepomis macrochirus. Les efforts de reproduction sont couteux sur le plan energetique et se traduisent souvent par d'importants compromis en ce qui concerne d'autres processus metaboliques. Chez de nombreux animaux, les androgenes influencent l'affectation de cette energie durant la saison de reproduction. Dans cette etude, les teneurs d'androgenes de crapets arlequins (Lepomis macrochirus Rafinesque, 1819) parentaux ont ete manipulees en implantant dans des males soit de la 11-cetotestosterone (11-KT) ou de la flutamide (un antagoniste des recepteurs d'androgenes) peu apres le frai. Les comportements parentaux ont ete evalues pendant 3 jours apres l'implantation. Les differences d'expression des genes du cerveau entre les deux groupes ont ete examinees a l'aide d'une puce a genes 44 000. Nous avons constate que les males dans lesquels avait ete implantee de la 11-KT presentaient des niveaux plus faibles d'expression de genes associes a la fonction immunitaire que les males ayant fait l'objet d'une implantation de flutamide, ce qui donne a penser que de fortes teneurs d'androgenes ont un effet negatif sur le systeme immunitaire des males. Ces donnees indiquent donc qu'il pourrait y avoir un important compromis entre le maintien de fortes teneurs d'androgenes et la reduction de la fonction immunitaire chez les crapets arlequins males parentaux. [Traduit par la Redaction] Mots-cles: fonction immunitaire, androgenes, soins parentaux, expression genique, crapet arlequin, Lepomis macrochirus., Introduction Reproduction is one of the most important times in the life of an individual because reproductive success is a main component of fitness. Reproduction is energetically costly, which leads [...]

Hemlock woolly adelgid (HWA), Adelges tsugae Annand, threatens hemlock forests throughout eastern North America. Management efforts focus on early detection of HWA to ensure rapid management responses to control and stop the spread of this pest. This study's goal was to identify an affordable, efficient trap to aid with airborne environmental DNA (eDNA) sampling approaches as an early monitoring tool for HWA. We initially compared HWA detection success between a standard sticky trap, commonly used for HWA monitoring, and trap designs potentially compatible with eDNA protocols (i.e. passive trap, funnel trap, and motorized trap). Passive, funnel, and motorized traps' estimated capture success probabilities compared to sticky traps were 0.87, 0.8, and 0.4, respectively. A secondary evaluation of a modified version of the motorized trap further assessed trap performance and determined the number of traps needed in a set area to efficiently detect HWA. By modifying the original motorized trap design, its estimated capture success probability increased to 0.67 compared to a sticky trap. Overall, the cumulative capture success over the 16-week sampling period for the motorized trap was 94% and 99% for the sticky trap. The number of traps did impact capture success, and trap elevation and distance to infested hemlocks influenced the number of adelgids captured per trap. As eDNA-based monitoring approaches continue to become incorporated into invasive species surveying, further refinement with these types of traps can be useful as an additional tool in the manager's toolbox. [ABSTRACT FROM AUTHOR]

Microplastics are ubiquitous in the world's aquatic environments, and their threat to aquatic biota is poorly understood, especially in freshwater ecosystems. In the environment, microbial biofilms can form on the surface of microplastics, which may sorb harmful toxins. While many laboratory-based studies use clean polymers under ecologically unrealistic conditions and concentrations, we incubated 500 μm polyethylene microplastic beads for 56 days in Muskegon Lake, Michigan, USA and used them to conduct a 28-day ingestion study with fathead minnows (Pimephales promelas). The study was conducted with a control group and two treatment groups, which received a low (4 beads) or high (16 beads) dose of weathered microplastics each day. We compared the treatment groups to the controls to assess the effects of weathered microplastic ingestion on growth (change in mass), condition factor, hematocrit, and fish gut microbial communities in both sexes. We also assessed the expression of three hepatic genes in males. Growth was lower in the high microplastic treatment group in male fathead minnows. The beta diversity of the gut microbial community was not impacted for either sex. There were some changes to alpha diversity metrics in males and several differentially abundant amplicon sequence variants (ASVs) in females. The expression of hepatic stress response genes was not altered in males. We also looked at the gut microbial community between sexes and over time within the control group and found clear differences, indicating that sex effects and environmental factors may have outweighed the impacts of microplastic ingestion on gut microbial diversity. [ABSTRACT FROM AUTHOR]

Background: Gypsophila paniculata (baby’s breath) is an invasive species found throughout much of the northwest United States and western Canada. Recently, plants exhibiting a different color morphology were identified within the coastal dunes along eastern Lake Michigan. The common baby’s breath (G. paniculata) typically produces stems that are purple in color (purple morph), while the atypical morph has stems that are green-yellow (green-yellow morph). The purpose of this study was to characterize these newly identified morphs and determine if they are genetically distinct species from the common baby’s breath in order to assess whether alternative management strategies should be employed to control these populations. Methods: We sequenced two chloroplast regions, ribulose-bisphosphate carboxylase gene (rbcL), and maturase K (matK), and one nuclear region, internal transcribed spacer 2 (ITS2), from the purple morphs and green-yellow morphs collected from Sleeping Bear Dunes National Lakeshore, MI, USA (SBDNL). Sequences were aligned to reference sequences from other Gypsophila species obtained from the Barcode of Life Database and GenBank databases. We also collected seeds from wild purple morph and wild green-yellow morph plants in SBDNL. We grew the seeds in a common garden setting and characterized the proportion of green-yellow individuals produced from the two color morphs after 5-months of growth. Results: Phylogenetic analyses based upon rbcL, matK, and ITS2 regions suggest that the two color morphs are not distinct species and they both belong to G. paniculata. Seeds collected from wild green-yellow morphs produced a significantly higher proportion of green-yellow individuals compared to the number produced by seeds collected from wild purple morphs. However, seeds collected from both color morphs produced more purple morphs than green-yellow morphs. Discussion: Based upon these results, we propose that the two color morphs are variants of G. paniculata. Given the significant difference in the number of green-yellow morphs produced from the seeds of each morph type, we also suggest that this color difference has some genetic basis. We propose that current management continue to treat the two color morphs in a similar manner in terms of removal to prevent the further spread of this species. [ABSTRACT FROM AUTHOR]

Premise of the Study: Gypsophila paniculata (baby's breath; Caryophyllaceae) is a herbaceous perennial that has invaded much of northern and western United States and Canada, outcompeting and crowding out native and endemic species. Microsatellite primers were developed to analyze the genetic structure of invasive populations. Methods and Results: We identified 16 polymorphic nuclear microsatellite loci for G. paniculata out of 73 loci that successfully amplified from a primer library created using Illumina sequencing technology. Microsatellite primers were developed to amplify di‐, tri‐, and tetranucleotide repeats and tested in three invasive populations in Michigan. Conclusions: These markers will be useful in characterizing the genetic structure of invasive populations throughout North America to aid targeted management efforts, and in native Eurasian populations to better understand invasion history. Five of these developed primers also amplified in G. elegans. [ABSTRACT FROM AUTHOR]

During the last few decades, biologists have made remarkable progress in understanding the fundamental processes that shape life. But despite the unprecedented level of knowledge now available, large gaps still remain in our understanding of the complex interplay of eco-evolutionary mechanisms across scales of life. Rapidly changing environments on Earth provide a pressing need to understand the potential implications of eco-evolutionary dynamics, which can be achieved by improving existing eco-evolutionary models and fostering convergence among the sub-fields of biology. We propose a new, data-driven approach that harnesses our knowledge of the functioning of biological systems to expand current conceptual frameworks and develop corresponding models that can more accurately represent and predict future eco-evolutionary outcomes. We suggest a roadmap toward achieving this goal. This long-term vision will move biology in a direction that can wield these predictive models for scientific applications that benefit humanity and increase the resilience of natural biological systems. We identify short, medium, and long-term key objectives to connect our current state of knowledge to this long-term vision, iteratively progressing across three stages: (1) utilizing knowledge of biological systems to better inform eco-evolutionary models, (2) generating models with more accurate predictions, and (3) applying predictive models to benefit the biosphere. Within each stage, we outline avenues of investigation and scientific applications related to the timescales over which evolution occurs, the parameter space of eco-evolutionary processes, and the dynamic interactions between these mechanisms. The ability to accurately model, monitor, and anticipate eco-evolutionary changes would be transformational to humanity's interaction with the global environment, providing novel tools to benefit human health, protect the natural world, and manage our planet's biosphere., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology.)