Millennial variability, hydrological and limnological changes during MIS3-2 in Lake Petén Itzá, GuatemalaRodrigo Martinez-Abarca, Michelle Abstein , Philipp Hoelzmann , Thorsten Bauersachs , Liseth Pérez , Mona Stockhecke , Sergio Cohuo Duran & Antje Schwalb
Heinrich Stadials and Greenland Interstadials are abrupt climate variations that are observed in the Northern Hemisphere throughout Marine Isotopic Stages (MIS) 3-2. Lake Petén Itzá, northern Guatemala, is a key site for paleoclimate investigations due to its sensitivity to changes in climate forcing such as the Intertropical Convergence Zone (ITCZ) and the Atlantic Meridional Overturning Circulation (AMOC). In this study, we reconstructed the hydrology and limnology of Lake Petén Itzá during MIS3-2 based on geochemical...
Virtually all land plants are coated in a cuticle, a waxy polyester that prevents nonstomatal water loss and is important for heat and drought tolerance. Here, we describe a likely genetic basis for a divergence in cuticular wax chemistry between Sorghum bicolor, a drought tolerant crop widely cultivated in hot climates, and its close relative Zea mays (maize). Combining chemical analyses, heterologous expression, and comparative genomics, we reveal that: 1) sorghum and maize leaf waxes...
Winter and summer zooplankton community and environmental parameters data of thirteen lakes located in Minnesota and WisconsinKirill Shchapov, Ted Ozersky & Paul Wilburn
This data set contains the results of a study on taxonomic and functional differences between winter and summer zooplankton communities in lakes across a trophic gradient. Thirteen lakes ('Sites.csv') were sampled across a large trophic status gradient for zooplankton abundance, taxonomic and functional community composition, and Carbon/Nitrogen (C/N) stable isotopes in relation to environmental parameters. Zooplankton abundance and taxonomic identification were made for all stations ('Zooplankton_abundance.csv'); nutrients and C/N stable isotopes values in file 'Environmental_parameters';...
Feather mercury increases with feeding at higher trophic levels in two species of migrant raptors, Merlin (Falco columbarius) and Sharp-shinned Hawk (Accipiter striatus)Edward Keyel, Matthew Etterson, Gerald Niemi, David Evers, Christopher DeSorbo, Joel Hoffman, John Nichols, Yang Li & Frank Nicoletti
Mercury (Hg) is a toxic heavy metal that, when methylated to form methylmercury (MeHg), bioaccumulates in exposed animals and biomagnifies through food webs. The purpose of this study was to assess Hg concentrations in raptors migrating through the upper Midwestern USA. From 2009-2012, 966 raptors of 11 species were captured at Hawk Ridge, Duluth, MN. Breast feathers were sampled to determine the concentration of total Hg. Mean Hg concentrations ranged from 0.11 – 3.46 μg...
Data from: A millennium of climatic and floristic dynamics in the Eastern Cordillera of the Colombian AndesAlex Correa, Jaime Escobar, Broxton Bird, Dayenari Caballero-Rodríguez, Byron Steinman, Paula A. Rodríguez-Zorro & Jason Curtis
The transition from the Medieval Climate Anomaly (MCA, 950-1250 CE) to the Little Ice Age (LIA, 1350 to 1800 CE) is the largest pre-industrial climate shift within the last two millennia, offering an opportunity to study how vegetation responds to rapid climate change. We analyzed a sedimentary record from the Colombian Andes to reconstruct regional vegetation dynamics during this time interval, identify the modern environmental distribution of taxa present in the fossil record, and provide...
Since 2005, investigators at UM Duluth's Large Lakes Observatory have been deploying sub-surface moorings in Lake Superior to investigate thermal structure and currents. This submission contains all temperature and current data from deployments that occurred in 2010.
From 2005 to the present, investigators from the Large Lakes Observatory at the University of Minnesota, Duluth have been deploying sub-surface moorings instrumented with temperature and current sensors at a variety of sites around Lake Superior. Temperature sensors at a range of depths, and profiling current meters were used to characterize the physical properties of the lake's water column. At one site, a nearly continuous time series of temperature throughout the water column exists from...
These data were collected as part of a two-year investigation into the impacts of beaver dam removal on low-flow hydrology and hydraulics in the Knife River, Minnesota, USA. Eight sub-basins were monitored for two years, organized as four pairs of sub-basins. The study focused on small headwater sub-basins, with areas ranging from 1.58 to 6.4 km2. In 2018, all of the study basins had active beaver dams. In 2019, the beavers were removed and dams...
Eight generations of native seed cultivation reduces plant fitness relative to the wild progenitor populationRiley Pizza, Erin Espeland & Julie Etterson
Native seed for restoration is in high demand, but widespread habitat degradation will likely prevent enough seed from being sustainably harvested from wild populations to meet this need. While propagation of native species has emerged in recent decades to address this resource gap, few studies have tested whether the processes of sampling from wild populations, followed by generations of farm cultivation, reduces plant fitness tolerance to stress over time. To test this, we grew the...
Assisted migration across fixed seed zones detects adaptation lags in two major North American tree speciesJulie R. Etterson, Meredith W. Cornett, Mark A. White & Laura Kavajecz
Boreal forests are experiencing dramatic climate change, having warmed 1-1.9°C over the last century. Yet forest regeneration practices are often still dictated by a fixed seed zone framework, in which seeds are both harvested from and planted into predefined areas. Our goal was to determine whether seedlings sourced from southern seed zones in Minnesota USA are already better adapted to northerly seed zones because of climate change. Bur oak (Quercus macrocarpa) and northern red oak...
Data and R code from: Relics of beavers past: time and population density drive scale-dependent patterns of ecosystem engineeringSean Johnson-Bice, Thomas Gable, Steve Windels & George Host
Like many ecological processes, natural disturbances exhibit scale-dependent dynamics that are largely a function of the magnitude, frequency, and scale at which they are assessed. Ecosystem engineers create patch-scale disturbances that affect ecological processes, yet we know little about how these effects scale across space or vary through time. Here, we investigate how patch disturbances by beavers (Castor canadensis), ecosystem engineers renowned for their pond-creation behavior, affect ecological processes across space and time. We evaluated...
“How could you even ask that?”: Moral Considerability, Uncertainty and Vulnerability in Social RoboticsAlexis Elder
When it comes to social robotics (robots that engage human social responses via “eyes” and other facial features, voice-based natural-language interactions, and even evocative movements), ethicists, particularly in European and North American traditions, are divided over whether and why they might be morally considerable. Some argue that moral considerability is based on internal psychological states like consciousness and sentience, and debate about thresholds of such features sufficient for ethical consideration, a move sometimes criticized for...
Title Supplementary Data and Code for 'On The Estimation of Internal Climate Variability During the Preindustrial Past Millennium'M.E. Mann, B.A. Steinman, D.J. Brouillette, A. Fernandez & S.K. Miller
We use an ensemble of simulations of a coupled model (NCAR Community Earth System Model) driven by natural radiative forcing estimates over the pre-industrial past millennium to test the efficacy of methods used previously to remove forced variability from proxy-based climate reconstructions and estimate residual internal variability (e.g. a putative "Atlantic Multidecadal Oscillation"). Within the framework of these experiments, the forced component of surface temperature change can be estimated accurately from the ensemble mean, and...
Supplementary data, code, and information for ‘Interhemispheric antiphasing of neotropical precipitation during the past millennium’ (PNAS, Steinman et al. 2022)B.A. Steinman, N. Stansall, M.E. Mann, C.A. Cooke, M.B. Abbott, M. Vuille, B.W. Bird, M.S. Lachniet & A. Fernandez
Uncertainty about the influence of anthropogenic radiative forcing on the position and strength of convective rainfall in the Intertropical Convergence Zone (ITCZ) inhibits our ability to project future tropical hydroclimate change in a warmer world. Paleoclimatic and modeling data inform on the timescales and mechanisms of ITCZ variability; yet a comprehensive, long-term perspective remains elusive. Here, we quantify the evolution of neotropical hydroclimate over the pre-industrial past millennium (850 to 1850 CE) using a synthesis...
A geographic mosaic of coevolution between Eurosta solidaginis (Fitch) and its host plant tall goldenrod Solidago altissima (L.)Timothy Craig & Joanne Itami
A geographic mosaic of coevolution has produced local reciprocal adaptation in tall goldenrod, Solidago altissima (L.), and the goldenrod ball gall fly, Eurosta solidaginis (Fitch 1855). The fly is selected to induce gall diameters that minimize mortality from natural enemies, and the plant is selected to limit gall growth that reduces plant fitness. We conducted a double reciprocal transplant experiment where S. altissima and E. solidaginis from three sites were grown in gardens at each...
Variation in frequency of plastid RNA editing within Adiantum (Pteridaceae) implies rapid evolution in fern plastomesBlake Fauskee, Erin Sigel, Kathleen Pryer & Amanda Grusz
Premise Recent advances in studies of plant RNA editing have demonstrated that the number of editing sites can vary widely among large taxonomic groups (orders, families). Yet, very little is known about intrageneric variation in frequency of plant RNA editing, and no study has been conducted in ferns. Methods We determined plastid RNA editing counts for two species of Adiantum (Pteridaceae), A. shastense and A. aleuticum, by implementing a pipeline that integrated read mapping and...
University of Minnesota, Duluth18
Pennsylvania State University2
Tecnológico Nacional de México, Mexico1
Biodiversity Research Institute1
TU-Braunschweig, Braunschweig, Germany1
Northern Illinois University1
University at Albany, State University of New York1
University of Alberta1
University of Minnesota1