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El decremento en las poblaciones naturales y manejadas de polinizadores ha situado el interés sobre el papel de los polinizadores, principalmente en el sector agrícola, por los efectos reportados en lo que se conoce como la “crisis de los polinizadores”. Dentro de los polinizadores más representativos se encuentran las abejas, y dentro de éstas, las abejas sin aguijón (Apidae: Meliponini). Estas últimas tienen gran relevancia ecológica, económica y cultural en el mundo y particularmente en México, por ser un grupo manejado desde hace cientos de años para obtención de miel y otros productos de la colmena. En esta revisión de literatura nos enfocamos en documentar lo que se sabe sobre las abejas sin aguijón en cuanto a su distribución, genética y ecología. En particular nos interesa resaltar aspectos sobre sus interacciones y los servicios ecosistémicos que proveen. Nuestro objetivo fue sintetizar la información disponible para México e identificar áreas de oportunidad en el estudio de estas abejas, con el fin de promover mejores estrategias de conservación y manejo. Encontramos que falta intensificar los estudios de este grupo para poder realizar un análisis de cómo los cambios ambientales afectan la riqueza de especies, abundancia, distribución e interacciones. Así mismo, la falta de estudios longitudinales nos impide conocer la magnitud del declive de estos polinizadores. Finalmente, proponemos incluir en los estudios de ecología y genética de abejas sin aguijón un enfoque de participación social, la cual puede proveer información muy valiosa sobre abejas nativas en México.

Ivermectin is an antiparasitic drug commonly used in cattle, that is excreted in dung, causing lethal and sub-lethal effects on coprophagous non-target fauna. Given that cattle parasites generate resistance to ivermectin, farmers have increased the used doses, with a consequent threat to wild fauna. The dung beetle speciesEuoniticellus intermediusprovides ecosystem services by burying dung in cattle pastures, however it is highly threatened by ivermectin. Here we experimentally tested whetherE. intermediusgenerates resistance against ivermectin after being exposed for several generations to a sublethal dose. We generated two laboratory lines where beetles were exposed to either ivermectin-treated or ivermectin-free dung for 18 generations. We compared reproductive success of beetles from both lines across generations. Additionally, for each line, we carried-out toxicity experiments with increasing ivermectin concentrations to determine if sensitivity to ivermectin was reduced after some generations of exposure (i. e. if beetles acquired ivermectin resistance by means of transgenerational effects). Our results show that dung beetles do not generate resistance to ivermectin after 18 generations of continuous exposure and quantitative genetic analyses show low genetic variation in response to ivermectin across generations. Together, these results indicate low potential for adaptation to the contaminant. According to our results, dung beetles, and probably other species, are at risk of extinction in ivermectin-contaminated pastures unless they are pre-adapted to tolerate high ivermectin concentrations.

Made available in DSpace on 2022-04-28T19:52:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-03-18 Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale. Department of Biology University of Toronto Mississauga ON Centre for Urban Environments University of Toronto Mississauga ON Department of Biology University of North Carolina, Chapel Hill Department of Biology University of Louisiana LA Department of Biology Queen's University ON Department of Biology Concordia University QC Department of Biological Sciences DePaul University Department of Biology DePauw University IN Department of Urban Design and Planning, University of Washington, Seattle, WA, USA Colegio de Ciencias Biológicas y Ambientales Universidad San Francisco de Quito USFQ Department of Genetics University of Georgia Department of Ecology and Genetics Evolutionary Biology Centre Uppsala University Field Science Center for Northern Biosphere Hokkaido University Natural History Museum Zoology University of New England NSW Programa de Pós-Graduação em Geografia da UFMT campus de Rondonópolis Department of Botany and Biodiversity Research Centre University of British Columbia Graduate Program in Genome Sciences and Technology Genome Sciences Centre University of British Columbia Department of Microbiology and Immunology University of British Columbia Red de Biología Evolutiva Instituto de Ecología A. C. School of the Environment Yale University CT Departamento de Ciencias Ecológicas Universidad de Chile, Facultad de Ciencias Instituto de Ecología y Biodiversidad Universidad de Chile Department of Biology Mount Allison University Red de Ecoetología Instituto de Ecología A. C. Department of Biology University of Ottawa ON Department of Zoology University of Cambridge Department of Biology, Washington University in St. Louis, St. Louis, MO, USA Department of Biology University of Miami FL Centro de Investigación en Recursos Naturales y Sustentabilidad (CIRENYS) Universidad Bernardo O'Higgins Department of Biology, University of La Verne, La Verne, CA, USA Département des sciences du bois et de la forêt Université Laval QC Evolution & Ecology Research Centre School of Biological Earth and Environmental Sciences UNSW Sydney NSW Department of Biology Ghent University Department of Biology Monmouth University West Long Branch Centre for Ecology Evolution and Environmental Changes Faculdade de Ciências Universidade de Lisboa Lisboa Department of Biology KU Leuven School of Agriculture and Environment Wildlife and Ecology group Massey University, Palmerston North Department of Biological Sciences University of Cape Town Institute of Landscape Ecology University of Münster Gosnell School of Life Sciences, Rochester Institute of Technology, Rochester, NY, USA Department of Biological Sciences University of Alberta AB Louis Calder Center and Department of Biological Sciences, Fordham University, Armonk, NY, USA Departamento de Ecología Tropical, Universidad Autónoma de Yucatán, Mérida, Yucatán, México School of Life Sciences University of Sussex Department of Ecology Environment and Plant Sciences Stockholm University iBIOTROP Instituto de Biodiversidad Tropical Universidad San Francisco de Quito Department of Biology, San Francisco State University, San Francisco, CA, USA Unidad de Recursos Naturales, Centro de Investigación Científica de Yucatán AC, Mérida, Yucatán, México School of Ecological and Environmental Sciences East China Normal University Shanghai Engineering Research Center of Sustainable Plant Innovation Centre for Ecosystem Science School of Biological Earth and Environmental Sciences UNSW Sydney NSW Department of Ecology and Evolutionary Biology University of Michigan MI Department of Biosciences Rice University TX IFEVA Universidad de Buenos Aires Facultad de Agronomía, CONICET Biology Department Saint Mary's University NS Department of Biological Sciences, Universidad de los Andes Department of Biology and Biochemistry University of Houston TX Université de Rennes Department of Zoology and Biodiversity Research Centre University of British Columbia Department of Environmental Studies Dordt University Sioux Center IA Department of Biology Minneapolis Community and Technical College MN Department of Natural Sciences Ecology and Environment Research Centre Manchester Metropolitan University Instituto de Investigaciones en Ecosistemas y Sustentabilidad UNAM Department of Botany School of Biology Aristotle University of Thessaloniki Faculty of Biological and Environmental Science Organismal & Evolutionary Biology Research Programme University of Helsinki Institute of Biodiversity Animal Health and Comparative Medicine University of Glasgow Department of Biology Hendrix College Department of Ecological Science Vrije Universiteit Amsterdam Departamento de Ciencias Biológicas y Agropecuarias Universidad Técnica Particular de Loja Departamento de Biologia Universidade Federal de Santa Maria (UFSM) Department of Plant Sciences School of Biology College of Science University of Tehran NTNU University Museum Norwegian University of Science and Technology Red de Estudios Moleculares Avanzados Instituto de Ecología A. C. School of Biological Sciences, University of Reading, Whiteknights Park, Reading, Berkshire, UK Department of Biology Northern Arizona University AZ Department of Biological Sciences MacEwan University AB Max Planck Institute for Plant Breeding Research Departamento de Ecología Evolutiva Instituto de Ecología Universidad Nacional Autónoma de México Max Planck Institute of Molecular Plant Physiology Potsdam-Golm BIO5 Institute University of Arizona AZ Alaska Center for Conservation Science University of Alaska Anchorage Tropical Diversity, Royal Botanical Garden of Edinburgh Département de biologie Université de Moncton Department of Biological Sciences University of Manitoba MB Departments of Microbiology & Statistics University of Manitoba MB Department of Biology University of New Brunswick Department of Biology Kalamazoo College MI BioProtection Research Centre Lincoln University Departamento de Ciencias Facultad de Artes Liberales Universidad Adolfo Ibáñez Department of Ecology Evolution Behaviour University of Minnesota MN Department of Biological Sciences Brock University Department of Environmental Toxicology, University of California, Davis, CA, USA ICB - University of Talca School of Molecular and Life Science Curtin University College of Science Health Engineering and Education Murdoch University, Murdoch School of Life and Environmental Sciences University of Sydney NSW School of Biological Sciences, Monash University, Melbourne, VIC, Australia Department of Biological Sciences Wayne State University MI Department of Biology Western Oregon University, OR School of Natural Resources and the Environment University of Arizona AZ Departamento de Ecología Humana, Cinvestav Mérida Departamento de Ciencias Biológicas y Departamento de Ecología y Biodiversidad Facultad de Ciencias de la Vida, Universidad Andrés Bello Institute of Ecology and Biodiversity (IEB) Department of Biology Lund University Department of Biology Norwegian University of Science and Technology Escuela Superiro de Desarrollo Sustentable Universidad Autónoma de Guerrero -CONACYT Clarkson Secondary School Peel District School Board ON Homelands Sr. Public School Peel District School Board ON Department of Biological Sciences University of Illinois at Chicago Dufferin-Peel Catholic District School Board, St. James Catholic Global Learning Centre Department of Biosciences University of Calgary AB Ecological Processes Branch U.S. Army ERDC-CERL Department of Biology, Oberlin College, Oberlin, OH, USA Escuela Nacional de Estudios Superiores Unidad Morelia UNAM Institute of Evolution and Ecology University of Tübingen Tübingen Department of Evolutionary Biology and Environmental Studies University of Zurich, Winterthurerstrasse Urban Wildlife Institute Department of Conservation and Science, Lincoln Park Zoo Departamento de Ecología Universidad Católica de la Santísima Concepción Department of Biological Sciences University of Denver CO Department of Biological Sciences Mississippi State University MS Department of Biology Center for Computational & Integrative Biology Rutgers University-Camden Kunming Institute of Botany Chinese Academy of Sciences Department of Chemistry & Biochemistry Laurentian University ON Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering College of Life Sciences Beijing Normal University School of BioSciences, University of Melbourne, Melbourne, VIC, Australia Posgrado en Ciencias Biológicas Universidad Nacional Autónoma de México Department of Biological Sciences, Auburn University, Auburn, AL, USA Department of Entomology and Nematology, University of California, Davis, CA, USA Department of Biology University of New Mexico NM Department of Biology University of Wisconsin - Eau Claire Agriculture Institute Iranian Research Organization for Science and Technology (IROST) Department of Biology Colby College ME Instituto de Biología Universidad de Antioquia Department of Biology University of Massachusetts Boston MA Agricultural Biology Colorado State University CO Departamento de Biología Vegetal y Ecología Facultad de Biología Universidad de Sevilla, Av. Reina Mercedes s/n Facultad de Estudios Interdisciplinarios Centro GEMA- Genómica Universidad Mayor Evolutionary Ecology Group Naturalis Biodiversity Center Department of Biology and Chemistry Nipissing University ON, North Bay Center for Ecological Research Kyoto University Bonanza Creek Long Term Ecological Research Program University of Alaska Fairbanks Department of Botany and Molecular Evolution Senckenberg Research Institute and Natural History Museum Frankfurt Departamento de Biodiversidade Instituto de Biociências Univ Estadual Paulista - UNESP Nelson Institute for Environmental Studies University of Wisconsin-Madison WI Department of Biology, California State University, Northridge, Los Angeles, CA, USA Department of Ecology Swedish University of Agricultural Sciences Facultad de Ciencias y Biotecnologia Universidad CES Department of Biology Hofstra University Faculty of Biosciences and Aquaculture Nord University, Bodø Division of Biological Sciences, University of California San Diego, San Diego, CA, USA Department of Biology University of Richmond VA Estación de Biodiversidad Tiputini Colegio de Ciencias Biológicas y Ambientales Universidad San Francisco de Quito USFQ Department of Biological Sciences Institute of Environment Florida International University FL Agronomy Department University of Almería Department of Biological Sciences and Center for Urban Ecology and Sustainability Butler University IN Department of Biological Sciences Louisiana State University LA Faculty of Biological Sciences, Goethe University Frankfurt Institute of Biology Leiden Leiden University Department of Biological and Environmental Science University of Jyväskylä Jyväskylä Department of Biology University of Louisville KY Organization for Programs on Environmental Science University of Tokyo CNRS AgroParisTech Ecologie Systématique et Evolution, Université Paris-Saclay Department of Biology, Providence College, Providence, RI, USA General Zoology Institute for Biology Martin Luther University Halle-Wittenberg International Arctic Research Center University of Alaska Fairbanks Science, Technology and Society Department, Rochester Institute of Technology, Rochester, NY, USA SLU Swedish Species Information Centre Swedish University of Agricultural Sciences Department of Biology Westfield State University MA Centre of New Technologies University of Warsaw Department of Biology, Stanford University, Stanford, CA, USA Plant Biology Department Michigan State University MI Biology Department Davidson College College of Horticulture and Forestry Sciences/ Hubei Engineering Technology Research Center for Forestry Information Huazhong Agricultural University School of Life Sciences Technical University of Munich School of Life Sciences Lanzhou University Institute of Ecology and Evolution University of Bern Department of Evolution Ecology and Behaviour University of Liverpool Departamento de Biodiversidade Instituto de Biociências Univ Estadual Paulista - UNESP

Ecosystem services provided by insects are threatened by recent increasing global temperatures, particularly in the tropics, where insects live close to their thermal limits. Given that tolerance to high temperatures depends on individual metabolism and physiological stress response, it may also be sensitive to other stressors that are common in natural and human-modified environments, such as pollution and parasite pressure. The effects of multiple stressors could be synergistic and can be particularly relevant in insects that provide highly valuable ecosystem services, such as dung beetles in cattle pastures. Here we measured heat tolerance (critical thermal maximum, CTmax) in dung beetles exposed to ivermectin, a toxic parasiticide excreted in cattle dung, with known negative effects on coprophagous fauna, and in beetles exposed to an immune challenge. We also exposed a group of beetles to a combination of both ivermectin and immune challenge to test for potential synergistic effects of both stressors. Contrary to our predictions, CTmax did not change with ivermectin exposure, but increased in immune-challenged beetles. As found in other insects, CTmax was higher in larger beetles, highlighting the importance of body size on thermal tolerance in ectotherms. We discuss potential mechanisms responsible of increased heat tolerance in immune-challenged beetles and highlight the importance of natural and human-induced environmental pressures that now interact with global warming and threaten ecosystem services provided by wild animals.

The maintenance of forest fragments within urban landscapes is essential for human well-being, as the loss of biodiversity may result in a reduction of ecological services in cities. Conserving diverse functional groups within urban landscapes is essential, since it is directly related with the resilience of such ecosystems. Through the use of indicator groups, it is possible to draw predictions on how communities respond to increasing urbanization. The goal of our study was to assess how the increase of urban land cover affects the assemblage and functional groups of dung beetles (Scarabaeinae) that inhabit forest fragments in a tropical city. We sampled dung beetles in nine fragments embedded in the metropolitan region of Joao Pessoa, Brazil. Increasing urbanization negatively affected the abundance of coprophagous species, as well as the species richness, abundance and biomass of roller beetles. Assemblages from the most urbanized forest fragments were significantly different from the other fragments. According to the decomposition of β diversity, species turnover was the main process shaping the dung beetle assemblages in Joao Pessoa. In this study we provide evidence that specific functional groups of dung beetles are affected by urbanization. Furthermore, as each functional group has different strategies to occupy habitats and use resources, urbanization has contrasting effects for each group. Our results confirm that dung beetles are highly sensitive to urbanization and that protected areas within cities are fundamental to conserve biodiversity and ecosystem services.

Ivermectin is a powerful antiparasitic drug commonly used in cattle. Ivermectin residues are excreted in dung, threatening non-target coprophagous fauna such as dung beetles. This can have severe ecological and economic consequences for dung degradation and soil fertility. Even though the negative effects of direct ivermectin exposure on dung-degrading organisms are well known, effects could extend across generations. Here, we tested the effects of paternal or maternal exposure to ivermectin on offspring in the dung beetle Euoniticellus intermedius. This species is a classic study subject in ecotoxicology and sexual selection because males have a cephalic horn that is under intense selection via male-male competition. After confirming a negative effect of ivermectin on the number of emerged beetles, we found trans-generational effects of ivermectin exposure on the horn size of male offspring. Surprisingly however, this trans-generational effect only occurred when only the father was exposed. We detected no trans-generational effects of ivermectin exposure on offspring number, sex ratio or body size. Our results confirm that ivermectin not only has a strong effect on exposed individuals but also in their progeny. Our study opens new questions about the mechanisms responsible for parental effects and their long-term fitness consequences in contaminated habitats.

The evolution of sexual dimorphism in species with separate sexes is influenced by the resolution of sexual conflicts creating sex differences through genetic linkage or sex-biased expression. Plants with different degrees of sexual dimorphism are thus ideal to study the genetic basis of sexual dimorphism. In this study we explore the genetic architecture of sexual dimorphism between Silene latifolia and Silene dioica. These species have chromosomal sex determination and differ in the extent of sexual dimorphism. To test whether QTL for sexually dimorphic traits have accumulated on the sex chromosomes and to quantify their contribution to species differences, we create a linkage map and performed QTL analysis of life history, flower and vegetative traits using an unidirectional interspecific F2 hybrid cross. We found support for an accumulation of QTL on the sex chromosomes and that sex differences explained a large proportion of the variance between species, suggesting that both natural and sexual selection contributed to species divergence. Sexually dimorphic traits that also differed between species displayed transgressive segregation. We observed a reversal in sexual dimorphism in the F2 population, where males tended to be larger than females, indicating that sexual dimorphism is constrained within populations but not in recombinant hybrids. This study contributes to the understanding of the genetic basis of sexual dimorphism and its evolution in Silene.

Pollen and stigma size have the potential to influence male fitness of hermaphroditic plants, particularly in species presenting floral polymorphisms characterised by marked differences in these traits among floral morphs. In this study, we take advantage of the evolutionary transition from tristyly to distyly experienced by Oxalis alpina (Oxalidaceae), and examined whether modifications in the ancillary traits (pollen and stigma size) respond to allometric changes in other floral traits. Also, we tested whether these modifications are in accordance with what would be expected under the hypothesis that novel competitive scenarios (as in distylous-derived reproductive system) exert morph- and whorl-specific selective pressures to match the available stigmas. We measure pollen and stigma size in five populations of O. alpina representing the tristyly-distyly transition. A general reduction in pollen and stigma size occurred along the tristyly-distyly transition, and pollen size from the two anther levels within each morph converged to a similar size that was characterised by whorl-specific changes (increases or decreases) in pollen size of different anthers in each floral type. Overall, results from this study show that the evolution of distyly in this species is characterised not only by changes in sexual organ position and flower size, but also by morph-specific changes in pollen and stigma size. This evidence supports the importance of selection on pollen and stigma size, which increase fitness of remaining morphs following the evolution of distyly, and raises questions to explore on the functional value of pollen size in heterostylous systems under pollen competition.

The immunocompetence handicap hypothesis (ICHH) states that hormones enhance sexual trait expression but impair immunity. Previous tests of the ICHH have been hampered by experimental design problems. Here, we report on an experimental test of the ICHH that includes manipulations of both hormones and infections in males of the territorial damselfly, Hetaerina americana, with accurate survival measurements. We conducted a fully factorial experiment subjecting each individual to one of three topical treatments: methoprene (a juvenile hormone analog), acetone, or control, and one of three injection treatments: bacteria, PBS, or control. We measured survival of manipulated males in both the wild and in captivity. As predicted, survival was most heavily impaired in methoprene-bacteria males than in the other groups in the wild, and no survival differences emerged in captive animals. This result confirms that survival is one cost an animal pays for increased hormonal levels. This corroborates theoretical predictions of the ICHH.