EEOB Publications October 1 - October 31
Algal blooms in a freshwater reservoir – A network community detection analysis of potential forcing parameters
Gerald R. Allen, Franklin W. Schwartz, David R. Cole, Roman P. Lanno, Anirudh Prabhu, Ahmed Eleish. Ecological Informatics, Volume 60, November 2020, 101168. https://doi.org/10.1016/j.ecoinf.2020.101168
Nutrient leakage due to modern agriculture and disposal of untreated urban wastewater results in the eutrophication of freshwater lakes and reservoirs, with elevated levels of cyanobacteria algal blooms often resulting in toxic conditions for animals and humans. A unique dataset of 22 coincident nutrient, phytoplankton, meteorological, and reservoir condition variables were recorded or calculated monthly for Hoover Reservoir near Columbus, Ohio, from February 1999 to December 2005. Network science was used in this study to visualize and differentiate selected nutrient and phytoplankton seasonality in Hoover Reservoir. Nutrient and phytoplankton concentrations in Hoover Reservoir respond independently to a number of external and internal environmental variables, but are also biochemically interdependent within the reservoir ecosystem. A number of forcing parameters can significantly alter seasonal phytoplankton growth and succession patterns. Chief among these are variability in the daily, seasonal, and/or yearly patterns and intensities of precipitation and the resultant surface runoff; duration and intensity of solar radiation; air and resultant water temperatures; and agricultural practices. The phytoplankton population in Hoover Reservoir is ecologically driven, with algal succession and nutrient levels constraining population concentrations. Complemented by selected statistical analyses, this limited network community detection study provides the hydrologist/ecologist with a dynamic and quantitative visualization of the complex hydrometeorological variable and biogeochemical process forcing parameters present in reservoirs and lakes.
Mesostigmatid mites associated with Oxysternon conspicillatum (Coleoptera: Scarabaeidae): a new species of Macrocheles, description of the male of M. magna, and four new records for Colombia
Edwin Javier Quintero-Gutiérrez, Orlando Cómbita-Heredia, and Hans Klompen. 2020. International Journal of Acarology, https://doi.org/10.1080/01647954.2020.1815838
Seven species of mites were found associated with the dung beetle Oxysternum conspicillatum in Colombia. Macrocheles neotransversus sp. nov. based on adults and the male of Macrocheles magna are described. Both species belong to the mitis species-group (Holocelaeno). Macrocheles boxi, M. phanaei, M. roquensis and Glyptholaspis confusa are reported for the first time in Colombia. Additionally, a case of hyperphoresy of deutonymphs of Histiostoma sp. on Megalolaelaps colossus is documented.
Resource supply governs the apparent temperature dependence of animal production in stream ecosystems
James R. Junker, Wyatt F. Cross, Jonathan P. Benstead, Alexander D. Huryn, James M. Hood, Daniel Nelson, Gı´sli M. Gı´slason, and Jon S. Olafsson. 2020. Ecology Letters. doi: 10.1111/ele.13608
Rising global temperatures are changing how energy and materials move through ecosystems, with potential consequences for the role of animals in these processes. We tested a central prediction of the metabolic scaling framework—the temperature independence of animal community production—using a series of geothermally heated streams and a comprehensive empirical analysis. We show that the apparent temperature sensitivity of animal production was consistent with theory for individuals (Epind = 0.64 vs. 0.65 eV), but strongly amplified relative to theoretical expectations for communities, both among (Epamong = 0.67 vs. 0 eV) and within (Epwithin = 1.52 vs. 0 eV) streams. After accounting for spatial and temporal variation in resources, we show that the apparent positive effect of temperature was driven by resource supply, providing strong empirical support for the temperature independence of invertebrate production and the necessary inclusion of resources in metabolic scaling efforts.
COSORE: A community database for continuous soil respiration and other soil‐atmosphere greenhouse gas flux data
Ben Bond‐Lamberty, Danielle S. Christianson, Avni Malhotra, Stephanie C. Pennington, Debjani Sihi, Amir AghaKouchak, Hassan Anjileli, M. Altaf Arain, Juan J. Armesto, Samaneh Ashraf, Mioko Ataka, Dennis Baldocchi, Thomas Andrew Black, Nina Buchmann, Mariah S. Carbone, Shih‐Chieh Chang, Patrick Crill, Peter S. Curtis, Eric A. Davidson, Ankur R. Desai, John E. Drake, Tarek S. El‐Madany, Michael Gavazzi, Carolyn‐Monika Görres, Christopher M. Gough, Michael Goulden, Jillian Gregg, Omar Gutiérrez del Arroyo, Jin‐Sheng He, Takashi Hirano, Anya Hopple, Holly Hughes, Järvi Järveoja, Rachhpal Jassal Jinshi Jian, Haiming Kan, Jason Kaye, Yuji Kominami, Naishen Liang, David Lipson, Catriona A. Macdonald, Kadmiel Maseyk, Kayla Mathes, Marguerite Mauritz, Melanie A. Mayes, Steve McNulty, Guofang Miao, Mirco Migliavacca, Scott Miller, Chelcy F. Miniat, Jennifer G. Nietz, Mats B. Nilsson, Asko Noormets, Hamidreza Norouzi, Christine S. O’Connell, Bruce Osborne, Cecilio Oyonarte, Zhuo Pang, Matthias Peichl, Elise Pendall, Jorge F. Perez‐Quezada, Claire L. Phillips, Richard P. Phillips, James W. Raich, Alexandre A. Renchon, Nadine K. Ruehr, Enrique P. Sánchez‐Cañete, Matthew Saunders, Kathleen E. Savage, Marion Schrumpf, Russell L. Scott, Ulli Seibt, Whendee L. Silver, Wu Sun, Daphne Szutu, Kentaro Takagi, Masahiro Takagi, Munemasa Teramoto, Mark G. Tjoelker, Susan Trumbore, Masahito Ueyama, Rodrigo Vargas, Ruth K. Varner, Joseph Verfaillie, Christoph Vogel, Jinsong Wang, Greg Winston, Tana E. Wood, Juying Wu, Thomas Wutzler, Jiye Zeng, Tianshan Zha, Quan Zhang, Junliang Zou. 2020. Global Change Biology. https://doi.org/10.1111/gcb.15353
Globally, soils store two to three times as much carbon as currently resides in the atmosphere, and it is critical to understand how soil greenhouse gas (GHG) emissions and uptake will respond to ongoing climate change. In particular, the soil‐to‐atmosphere CO2 flux, commonly though imprecisely termed soil respiration (RS), is one of the largest carbon fluxes in the Earth system. An increasing number of high‐frequency RS measurements (typically, from an automated system with hourly sampling) have been made over the last two decades; an increasing number of methane measurements are being made with such systems as well. Such high frequency data are an invaluable resource for understanding GHG fluxes, but lack a central database or repository. Here we describe the lightweight, open‐source COSORE (COntinuous SOil REspiration) database and software, that focuses on automated, continuous and long‐term GHG flux datasets, and is intended to serve as a community resource for earth sciences, climate change syntheses and model evaluation. Contributed datasets are mapped to a single, consistent standard, with metadata on contributors, geographic location, measurement conditions and ancillary data. The design emphasizes the importance of reproducibility, scientific transparency and open access to data. While being oriented towards continuously measured RS, the database design accommodates other soil‐atmosphere measurements (e.g. ecosystem respiration, chamber‐measured net ecosystem exchange, methane fluxes) as well as experimental treatments (heterotrophic only, etc.). We give brief examples of the types of analyses possible using this new community resource and describe its accompanying R software package.
Racist Words in Science
Joan M Herbers. 2020. BioScience, biaa113, https://doi.org/10.1093/biosci/biaa113
Current interest in identifying and eliminating systemic racism, sparked by the Black Lives Matter movement, has prompted name changes for performing artists, sports teams, and food items. Offensive statues are being removed, and powerful symbols like the Confederate flag are becoming scarcer. We are reexamining public art, the names on buildings, and other symbols. This movement has also instigated the scrutiny of everyday words that may hearken back to our dark history of slavery and genocide. A recent CNN article pointed out terms that have racist etymology (www.cnn.com/2020/07/06/us/racism-words-phrases-slavery-trnd/index.html), and I submit that it is time for scientists to rethink the words we use as well.
Promoting inclusion in ecological field experiences: Examining and overcoming barriers to a professional rite of passage
N. Morales, K. Bisbee O’Connell, S. McNulty, A. Berkowitz, G. Bowser, M. Giamellaro, and M. N. Miriti. 2020. Bull Ecol Soc Am 00(00):e01742. https://doi.org/10.1002/bes2.1742
Field experiences can provide transformative opportunities for many individuals who eventually pursue ecology, natural resource, and conservation careers. However, some of the same elements of field‐based programs that define and provide pivotal experiences for some represent barriers for others, especially students from underrepresented groups. Barriers may be financial, physical, cultural, or social. Issues of gender, identity, and race/ethnicity, for example, can be isolating or shut down learning during intensive field experiences when group leaders are not prepared to respond
to interpersonal challenges. We explore some benefits and barriers presented by field learning experiences as well as some challenges and potential strategies to broaden inclusivity with the hope of encouraging further conversation on diversity and inclusion in field experiences.
Effects of Hypoxia on Habitat Quality of Reservoir Largemouth Bass, Saugeye, and White Crappie
Richard R. Budnik Geoffrey B. Steinhart Joseph D. Conroy Rebecca A. Dillon Richard D. Zweifel Stuart A. Ludsin. 2020. Transactions of the American Fisheries Society. https://doi.org/10.1002/tafs.10272
Hypoxia induced by eutrophication and high summer temperatures is common in most Midwestern reservoirs, with uncertain effects on resident fishes. To evaluate the potential influence of low dissolved oxygen and high temperature conditions on habitat quality for three common sport fishes (Largemouth Bass Micropterus salmoides, saugeye Sander vitreus × S. canadensis, and White Crappie Pomoxis annularis), we used spatially‐explicit bioenergetics models to measure growth rate potential (GRP) in three Ohio reservoirs of varying productivity and size. Dissolved oxygen (DO), temperature, and prey biomass data were collected throughout each study reservoir during August 2015 or 2016, when temperature and hypoxia levels were expected to be at or near their peak. Growth rate potential was generally low in hypoxic bottom waters, and higher in the epilimnion due to prey concentrating above the oxycline. The amount of high quality habitat (HQH; i.e., GRP > 0 g/g/d) always declined, owing to hypoxia; however, the extent of the decline depended on the species and reservoir modeled. Among species, hypoxia‐induced losses of HQH were small, differing by < 8% in each reservoir. Among‐reservoir differences in HQH were greater; reductions in HQH ranged from 31.3–42.5% among species in the reservoir with the lowest DO (mean ± SE; 2.7 ± 0.04 mg/L) and highest gape‐appropriate prey biomass (5.1 ± 0.07–5.3 ± 0.07 g/m3), whereas they varied by 0.3–0.6% in the reservoir with the highest DO (5.1 ± 0.07 mg/L) and lowest gape‐appropriate prey biomass (0.2 ± 0.004–0.6 ± 0.01 g/m3). Even so, the reservoir with the lowest mean DO (i.e., greatest hypoxic extent) had the highest mean GRP and percentage HQH owing to high prey biomass. Collectively, our findings indicate that bottom hypoxia can reduce sport fish habitat quality in temperate reservoirs, but high prey biomass may mitigate the negative effect of hypoxia.
Global functional and phylogenetic structure of avian assemblages across elevation and latitude
Jarzyna MA, Quintero I, Jetz W. Ecology Letters, 29 Oct 2020, DOI: 10.1111/ele.13631
Mountain systems are exceptionally species rich, yet the associated elevational gradients in functional and phylogenetic diversity and their consistency across latitude remain little understood. Here, we document how avian functional and phylogenetic diversity and structure vary along all major elevational gradients worldwide and uncover strong latitudinal differences. Assemblages in warm tropical lowlands and cold temperate highlands are marked by high functional overdispersion and distinctiveness, whereas tropical highlands and temperate lowlands appear strongly functionally clustered and redundant. We additionally find strong geographic variation in the interplay of phylogenetic and functional structure, with strongest deviations between the two in temperate highlands. This latitudinal and elevational variation in assemblage functional structure is underpinned by nuanced shifts in the position, shape and composition of multivariate trait space. We find that, independent of latitude, high-elevation assemblages emerge as exceptionally susceptible to functional change.
Glucocorticoids do not promote prosociality in a wild group-living fish.
Culbert BM, Ligocki IY, Salena MG, Wong MYL, Bernier NJ, Hamilton IM, Balshine S. Hormones and Behavior, 25 Oct 2020, :104879. DOI: 10.1016/j.yhbeh.2020.104879
Individuals often respond to social disturbances by increasing prosociality, which can strengthen social bonds, buffer against stress, and promote overall group cohesion. Given their importance in mediating stress responses, glucocorticoids have received considerable attention as potential proximate regulators of prosocial behaviour during disturbances. However, previous investigations have largely focused on mammals and our understanding of the potential prosocial effects of glucocorticoids across vertebrates more broadly is still lacking. Here, we assessed whether experimentally elevated glucocorticoid levels (simulating endogenous cortisol responses mounted following disturbances) promote prosocial behaviours in wild groups of the cichlid fish, Neolamprologus pulcher. Using SCUBA in Lake Tanganyika, we observed how subordinate group members adjusted affiliation, helping, and submission (all forms of prosocial behaviour) following underwater injections of either cortisol or saline. Cortisol treatment reduced affiliative behaviours-but only in females-suggesting that glucocorticoids may reduce overall prosociality. Fish with elevated glucocorticoid levels did not increase performance of submission or helping behaviours. Taken together, our results do not support a role for glucocorticoids in promoting prosocial behaviour in this species and emphasize the complexity of the proximate mechanisms that underlie prosociality.
Venom Function of a New Species of Megalomyrmex Forel, 1885 (Hymenoptera: Formicidae)
Kyle Sozanski, Lívia Pires do Prado, Andrew J. Mularo, Victoria A. Sadowski, Tappey H. Jones and Rachelle M. M. Adams. Toxins 2020, 12(11), 679; https://doi.org/10.3390/toxins12110679
Alkaloids are important metabolites found across a variety of organisms with diverse ecological functions. Of particular interest are alkaloids found in ants, organisms well known for dominating the ecosystems they dwell in. Within ants, alkaloids are found in venom and function as potent weapons against heterospecific species. However, research is often limited to pest species or species with parasitic lifestyles and thus fails to address the broader ecological function of ant venom alkaloids. Here we describe a new species of free-living Megalomyrmex ant: Megalomyrmex peetersi sp. n. In addition, we identify its singular venom alkaloid (trans-2-butyl-5-heptylpyrrolidine) and elucidate the antibiotic and insecticidal functions of its venom. Our results show that Megalomyrmex peetersi sp. n. venom is an effective antibiotic and insecticide. These results are comparable to venom alkaloids found in other ant species, such as Solenopsis invicta. This research provides great insight into venom alkaloid function, and it is the first study to explore these ideas in the Megalomyrmex system.
A Brief History of the Major Rickettsioses in the Asia–Australia–Pacific Region: A Capstone Review for the Special Issue of TMID
Daniel H. Paris, Daryl J. Kelly, Paul A. Fuerst, Nicholas P. J. Day and Allen L. Richards. Trop. Med. Infect. Dis. 2020, 5, 165; doi:10.3390/tropicalmed5040165
The rickettsioses of the “Far East” or Asia–Australia–Pacific region include but are not limited to endemic typhus, scrub typhus, and more recently, tick typhus or spotted fever. These diseases embody the diversity of rickettsial disease worldwide and allow us to interconnect the various contributions to this special issue of Tropical Medicine and Infectious Disease. The impact of rickettsial diseases—particularly of scrub typhus—was substantial during the wars and “police actions” of the last 80 years. However, the post-World War II arrival of effective antibiotics reduced their impact, when recognized and adequately treated (chloramphenicol and tetracyclines). Presently, however, scrub typhus appears to be emerging and spreading into regions not previously reported. Better diagnostics, or higher population mobility, change in antimicrobial policies, even global warming, have been proposed as possible culprits of this phenomenon. Further, sporadic reports of possible antibiotic resistance have received the attention of clinicians and epidemiologists, raising interest in developing and testing novel diagnostics to facilitate medical diagnosis. We present a brief history of rickettsial diseases, their relative importance within the region, focusing on the so-called “tsutsugamushi triangle”, the past and present impact of these diseases within the region, and indicate how historically, these often-confused diseases were ingeniously distinguished from each another. Moreover, we will discuss the importance of DNA-sequencing efforts for Orientia tsutsugamushi, obtained from patient blood, vector chiggers, and rodent reservoirs, particularly for the dominant 56-kD type-specific antigen gene (tsa56), and whole-genome sequences, which are increasing our knowledge of the diversity of this unique agent. We explore and discuss the potential of sequencing and other effective tools to geographically trace rickettsial disease agents, and develop control strategies to better mitigate the rickettsioses.
Multiple signals predict male mating success in the lek-mating lesser prairie-chicken (Tympanuchus pallidicinctus)
Geoffrey M. Gould & Jacqueline K. Augustine. Behavioral Ecology and Sociobiology volume 74, Article number: 137 (2020)
Sexual selection theory maintains that traits under selection honestly advertise qualities of signaling individuals and that only individuals in the best condition can survive while displaying maximally elaborated secondary sexual ornaments. Recent trends in mate choice studies have favored the consideration of the effects of multiple traits on mating success, including suites of traits transmitted in different sensory modalities. Sexual selection is expected to be especially strong in lek-mating species. The lesser prairie-chicken (Tympanuchus pallidicinctus) is a grouse species which breeds on leks. Males of this species perform audio and locomotor displays and exhibit two pairs of brightly colored ornaments. We performed an observational study of mate choice in spring 2016–2018 and noted 40 copulations on seven leks. We quantified behavioral, territorial, and morphological characteristics of males along with ornament color properties. We found that variables from all categories considered predicted female choice. Age had the strongest effect, with adult males experiencing higher female choice relative to yearlings. Allocation of aggressive behavior and comb color properties were also strongly correlated with female choice. Our results show that modulating behavior depending on whether females are present contributes to male mating success and highlight the importance of the size and color properties of secondary ornaments. Further research is required to determine how the variables most strongly associated with mate choice relate to one another and which aspects of individual quality, if any, are signaled by color ornaments. Future studies could also incorporate variables related to females to determine if selection on females occurs.
Using trace elements to identify the geographic origin of migratory bats
Jamin G. Wieringa, Juliet Nagel, David M. Nelson, Bryan C. Carstens, H. Lisle Gibbs. 2020. PeerJ 8:e10082 https://doi.org/10.7717/peerj.10082
The expansion of the wind energy industry has had benefits in terms of increased renewable energy production but has also led to increased mortality of migratory bats due to interactions with wind turbines. A key question that could guide bat-related management activities is identifying the geographic origin of bats killed at wind-energy facilities. Generating this information requires developing new methods for identifying the geographic sources of individual bats. Here we explore the viability of assigning geographic origin using trace element analyses of fur to infer the summer molting location of eastern red bats (Lasiurus borealis). Our approach is based on the idea that the concentration of trace elements in bat fur is related through the food chain to the amount of trace elements present in the soil, which varies across large geographic scales. Specifically, we used inductively coupled plasma–mass spectrometry to determine the concentration of fourteen trace elements in fur of 126 known-origin eastern red bats to generate a basemap for assignment throughout the range of this species in eastern North America. We then compared this map to publicly available soil trace element concentrations for the U.S. and Canada, used a probabilistic framework to generate likelihood-of-origin maps for each bat, and assessed how well trace element profiles predicted the origins of these individuals. Overall, our results suggest that trace elements allow successful assignment of individual bats 80% of the time while reducing probable locations in half. Our study supports the use of trace elements to identify the geographic origin of eastern red and perhaps other migratory bats, particularly when combined with data from other biomarkers such as genetic and stable isotope data.