Vulnerability of megapodes (Megapodiidae, Aves) to climate change and related threats

2018 ◽  
Vol 45 (4) ◽  
pp. 396-406 ◽  
Author(s):  
PAUL M. RADLEY ◽  
ROBERT A. DAVIS ◽  
RENÉ W.R.J. DEKKER ◽  
SHAUN W. MOLLOY ◽  
DAVID BLAKE ◽  
...  
Keyword(s):  
Climate Change ◽  
Gene Flow ◽  
Life Histories ◽  
Population Level ◽  
Genetic Connectivity ◽  
Future Research ◽  
Mean Annual Temperature ◽  
Climate Variables ◽  
Microbial Decomposition ◽  
Anthropogenic Habitat

SUMMARYAspects of species life histories may increase their susceptibility to climate change. Owing to their exclusive reliance on environmental sources of heat for incubation, megapodes may be especially vulnerable. We employed a trait-based vulnerability assessment to weigh their exposure to projected climate variables of increasing temperatures, fluctuating rainfall and sea level rise and their biological sensitivity and capacity to adapt. While all 21 species were predicted to experience at least a 2 °C increase in mean annual temperature, 12 to experience a moderate or greater fluctuation in rainfall and 16 to experience rising seas, the most vulnerable megapodes are intrinsically rare and range restricted. Species that employ microbial decomposition for incubation may have an adaptive advantage over those that do not and may be more resilient to climate change. The moderate microclimate necessary for mound incubation, however, may in some areas be threatened by anthropogenic habitat loss exacerbated by warmer and seasonally drier conditions. As with many avian species, little is known about the capacity of megapodes to adapt to a changing climate. We therefore recommend that future research efforts investigate megapode fecundity, gene flow and genetic connectivity at the population level to better determine their adaptive capacity.

scholarly journals Recent large-scale landscape changes, genetic drift and reintroductions characterize the genetic structure of Norwegian wild reindeer

2019 ◽  
Vol 20 (6) ◽  
pp. 1405-1419 ◽  
Author(s):  
Kjersti S. Kvie ◽  
Jan Heggenes ◽  
Bård-Jørgen Bårdsen ◽  
Knut H. Røed
Keyword(s):  
Genetic Variation ◽  
Gene Flow ◽  
Genetic Structure ◽  
Population Size ◽  
Genetic Drift ◽  
Genetic Connectivity ◽  
Conservation Strategies ◽  
Landscape Changes ◽  
Anthropogenic Habitat ◽  
Wild Reindeer

Abstract Landscape changes, such as habitat loss and fragmentation, subdivide wild populations, reduce their size, and limit gene flow. These changes may further lead to depletion of genetic variation within populations as well as accelerating differentiation among populations. As a migratory species requiring large living areas, wild reindeer (Rangifer tarandus) is highly vulnerable to human activity. The number and continued presence of wild reindeer have been significantly reduced due to accelerating anthropogenic habitat modifications, as well as displacement in benefit of domesticated herds of the species. As a basis for future management strategies we assess genetic structure and levels of genetic variation in Norwegian wild reindeer by analysing 12 microsatellite loci and the mitochondrial control region in 21 management units with varying population sizes. Overall, both markers showed highly varying levels of genetic variation, with reduced variation in the smaller and more isolated populations. The microsatellite data indicated a relationship between population size and genetic variation. This relationship was positive and linear until a threshold for population size was reached at approximately 1500 reindeer. We found high levels of differentiation among most populations, indicating low levels of gene flow, but only a weak correlation between geographic and genetic distances. Our results imply that the genetic structure of Norwegian wild reindeer is mainly driven by recent colonization history, population size, as well as human-induced landscape fragmentation, restricting gene flow and leading to high levels of genetic drift. To sustain viable populations, conservation strategies should focus on genetic connectivity between populations.

scholarly journals Asymmetrical gene flow in five co-distributed syngnathids explained by ocean currents and rafting propensity

2020 ◽  
Vol 287 (1926) ◽  
pp. 20200657 ◽  
Author(s):  
Laura D. Bertola ◽  
J. T. Boehm ◽  
Nathan F. Putman ◽  
Alexander T. Xue ◽  
John D. Robinson ◽  
...  
Keyword(s):  
Gene Flow ◽  
Ocean Circulation ◽  
Habitat Preferences ◽  
Population Level ◽  
Ocean Currents ◽  
Genetic Connectivity ◽  
Dispersal Ability ◽  
Genome Wide ◽  
Near Shore ◽  
Species Specific

Ocean circulation driving macro-algal rafting is believed to serve as an important mode of dispersal for many marine organisms, leading to predictions on population-level genetic connectivity and the directionality of effective dispersal. Here, we use genome-wide single nucleotide polymorphism data to investigate whether gene flow directionality in two seahorses ( Hippocampus ) and three pipefishes ( Syngnathus ) follows the predominant ocean circulation patterns in the Gulf of Mexico and northwestern Atlantic. In addition, we explore whether gene flow magnitudes are predicted by traits related to active dispersal ability and habitat preference. We inferred demographic histories of these co-distributed syngnathid species, and coalescent model-based estimates indicate that gene flow directionality is in agreement with ocean circulation data that predicts eastward and northward macro-algal transport. However, the magnitude to which ocean currents influence this pattern appears strongly dependent on the species-specific traits related to rafting propensity and habitat preferences. Higher levels of gene flow and stronger directionality are observed in Hippocampus erectus , Syngnathus floridae and Syngnathus louisianae , which closely associated with the pelagic macro-algae Sargassum spp., compared to Hippocampus zosterae and the Syngnathus scovelli / Syngnathus fuscus sister-species pair, which prefer near shore habitats and are weakly associated with pelagic Sargassum . This study highlights how the combination of population genomic inference together with ocean circulation data can help explain patterns of population structure and diversity in marine ecosystems.

Predicting the impact of increasing temperatures on seed germination among populations of Western Australian Banksia (Proteaceae)

2014 ◽  
Vol 24 (3) ◽  
pp. 195-205 ◽  
Author(s):  
Anne Cochrane ◽  
Gemma L. Hoyle ◽  
Colin J. Yates ◽  
Jeff Wood ◽  
Adrienne B. Nicotra
Keyword(s):  
Climate Change ◽  
Seed Germination ◽  
Natural Populations ◽  
Population Level ◽  
Germination Percentage ◽  
Individual Species ◽  
Mean Annual Temperature ◽  
Consistent Manner ◽  
The Impact ◽  
Germination Niche

AbstractTemperature is a significant factor influencing seed germination and for many species temperature-mediated germination cues are vital for plant persistence. Rising temperatures forecast as a result of anthropogenic climate change may have a substantial influence on the population and range dynamics of plant species. Here, we report on the thermal constraints on seed germination in natural populations of four congeneric Banksia species collected from a longitudinal climate gradient in Western Australia. We investigated whether germination niche: (1) varied between species; (2) varied among populations of each species; and (3) varied in a consistent manner reflecting the climatic gradients of seed origin. We hypothesized that species would differ and that populations from warmer sites would have a broader temperature window for germination than populations from cooler sites. Species differed in the breadth of their germination niche, but temperatures that stimulated the most rapid and complete germination were similar across all species. A sharp reduction in germination percentage occurred above the optimum temperature, which coincided with significant delays in germination relative to the optimum. The temperatures causing these declines varied among populations. Across the species, there was a significant correlation between optimum germination temperature and mean annual temperature at seed source; however, there was no relationship at the population level for individual species. These data provide insight into the vulnerability of Banksia species to climate change, with those populations that require lower temperatures for germination, or have narrower optimal ranges for germination, likely to be most vulnerable to a warming climate.

scholarly journals The relative contribution of natural landscapes and human-mediated factors on the connectivity of a noxious invasive weed

2016 ◽  
Author(s):  
Diego F. Alvarado-Serrano ◽  
Megan Van Etten ◽  
Shu-Mei Chang ◽  
Regina S. Baucom
Keyword(s):  
Gene Flow ◽  
Population Differentiation ◽  
Environmental Changes ◽  
Anthropogenic Impacts ◽  
Population Connectivity ◽  
Genetic Connectivity ◽  
Future Research ◽  
Invasive Weed ◽  
Relative Contribution ◽  
Genome Wide

ABSTRACTExamining how the landscape may influence gene flow is at the forefront of understanding population differentiation and adaptation. Such understanding is crucial in light of ongoing environmental changes and the elevated risk of ecosystems alteration. In particular, knowledge of how humans may influence the structure of populations is imperative to allow for informed decisions in management and conservation as well as to gain a better understanding of anthropogenic impacts on the interplay between gene flow, genetic drift and selection. Here we use genome-wide molecular markers to characterize the population genetic structure and connectivity of Ipomoea purpurea, a noxious invasive weed. We likewise assess the interaction between natural and human-driven influences on genetic differentiation among populations. Our analyses find that human population density is an important predictor of pairwise population differentiation, suggesting that the agricultural and/or horticultural trade may be involved in maintaining some level of connectivity across distant agricultural fields. Climatic variation appears as an additional predictor of genetic connectivity in this species. We discuss the implications of these results and highlight future research needed to disentangle the mechanistic processes underlying population connectivity of weeds.

scholarly journals The genetics of assisted gene flow: immediate costs and long-term benefits

2021 ◽  
Author(s):  
Jared A. Grummer ◽  
Tom R. Booker ◽  
Remi Matthey-Doret ◽  
Pirmin Nietlisbach ◽  
Andréa T. Thomaz ◽  
...  
Keyword(s):  
Climate Change ◽  
Genetic Variation ◽  
Gene Flow ◽  
Genetic Material ◽  
Population Level ◽  
Physiological Adaptation ◽  
Outbreeding Depression ◽  
Climate Change Scenarios ◽  
Animal Populations

ABSTRACTPlant and animal populations are facing several novel risks such as human-mediated habitat fragmentation and climate change that threaten their long-term productivity and persistence. With the genetic health of many populations deteriorating due to climate change outpacing physiological adaptation, human interventions in the form of assisted gene flow (AGF) may provide genetic variation to adapt populations to predicted climate change scenarios and result in more robust and productive populations. We ran genetic simulations to mimic a variety of AGF scenarios and measured their outcomes on population-level fitness to answer the question: in which circumstances is it worthwhile to perform AGF? Based on the parameters we explored, AGF may be harmful in certain situations over the short term (e.g., the first ∼10-20 generations), due to outbreeding depression and introducing deleterious genetic variation. Moreover, under many parameter sets, the benefits of AGF were relatively weak or took many generations to accrue. In general, when the adaptive trait is controlled by many loci of small effect, the benefits of assisted gene flow take much longer to realize–potentially too long for most climate-related management decisions. We also show that when translocation effort is divided across several generations and outbreeding depression is strong, the recipient population experiences a smaller decrease in fitness as compared to moving all individuals in a single effort. Importantly, in most cases, we show that the genomic integrity of the recipient population remains relatively intact following AGF; the amount of genetic material from the donor population typically ends up constituting no more of the recipient population’s genome than the fraction introduced. Our results will be useful for conservation practitioners and silviculturists, for instance, aiming to intervene and adaptively manage so that populations maintain a robust genetic health and maintain productivity into the future given anthropogenic climate change.

scholarly journals Detecting climate signals in populations across life histories

2021 ◽  
Author(s):  
Stephanie Jenouvrier ◽  
Matthew C. Long ◽  
Christophe Coste ◽  
Marika Holland ◽  
Marlène Gamelon ◽  
...  
Keyword(s):  
Climate Change ◽  
Population Dynamics ◽  
Life Histories ◽  
Natural Variability ◽  
Climate Impacts ◽  
Future Research ◽  
Emperor Penguin ◽  
Climate Trends ◽  
Functional Relationships ◽  
Climate Signals

Climate impacts are not always easily discerned in wild populations as climate change occurs in the context of natural variability. Furthermore, species responses to climate change and variability differ among life histories. The time of emergence (ToE) identifies when the signal of anthropogenic climate change can be quantitatively distinguished from noise associated with natural variability. This concept has been applied extensively in the climate sciences, but has not yet formally been explored in the context of population dynamics. Here, we present a theoretical assessment of the ToE of climate-driven signals in population dynamics (ToEpop) to detect climate signals in populations. We identify the dependence of ToEpop on the magnitude of climate trends and variability and explore the demographic controls on ToEpop. We demonstrate that different life histories (fast species vs. slow species), demographic processes (survival, reproduction) and functional relationships between climate and demographic rates, yield population dynamics that filter trends and variability in climate differently. We illustrate empirically how to detect the point in time when anthropogenic signals in populations emerge from the envelope of natural variability for a species threatened by climate change: the emperor penguin. Finally, we propose six testable hypotheses and a road map for future research.

Systematics and evolution of Lentibulariaceae: III. Utricularia

2018 ◽  
Author(s):  
Richard W. Jobson ◽  
Paulo C. Baleeiro ◽  
Cástor Guisande
Keyword(s):  
Gene Flow ◽  
Species Diversity ◽  
Population Level ◽  
Oceanic Islands ◽  
Vulnerable Species ◽  
Phylogenetic Studies ◽  
Molecular Phylogenetic

Utricularia is a morphologically and ecologically diverse genus currently comprising more than 230 species divided into three subgenera—Polypompholyx, Utricularia, and Bivalvaria—and 35 sections. The genus is distributed worldwide except on the poles and most oceanic islands. The Neotropics has the highest species diversity, followed by Australia. Compared to its sister genera, Utricularia has undergone greater rates of speciation, which are linked to its extreme morphological flexibility that has resulted in the evolution of habitat-specific forms: terrestrial, rheophytic, aquatic, lithophytic, and epiphytic. Molecular phylogenetic studies have resolved relationships for 44% of the species across 80% of the sections. Scant data are available for phylogeography or population-level processes such as gene flow, hybridization, or pollination. Because nearly 90% of the species are endemics, data are urgently needed to determine how to protect vulnerable species and their habitats.

Twitter Users’ Displays of Affect in the Global Warming Debate

2021 ◽  
pp. 004728162110078
Author(s):  
Shanna Cameron ◽  
Alexandra Russell ◽  
Luke Brake ◽  
Katherine Fredlund ◽  
Angela Morris
Keyword(s):  
Climate Change ◽  
Social Media ◽  
Global Warming ◽  
Content Analysis ◽  
Technical Communication ◽  
Research Team ◽  
Future Research ◽  
Climate Change Research ◽  
Quantitative Content ◽  
Twitter Users

This article engages with recent discussions in the field of technical communication that call for climate change research that moves beyond the believer/denier dichotomy. For this study, our research team coded 900 tweets about climate change and global warming for different emotions in order to understand how Twitter users rely on affect rhetorically. Our findings use quantitative content analysis to challenge current assumptions about writing and affect on social media, and our results indicate a number of arenas for future research on affect, global warming, and rhetoric.

scholarly journals Climate Change Sustainability: From Bargaining to Cooperative Balanced Approach

Games ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 45
Author(s):  
Tiziana Ciano ◽  
Massimiliano Ferrara ◽  
Mariangela Gangemi ◽  
Domenica Stefania Merenda ◽  
Bruno Antonio Pansera
Keyword(s):  
Climate Change ◽  
Cooperative Game Theory ◽  
Research Field ◽  
Future Research ◽  
Open Problems ◽  
Cooperative Approach ◽  
Change Dynamics ◽  
Bargaining Solutions ◽  
Balanced Approach ◽  
Competitive Bargaining

This work aims to provide different perspectives on the relationships between cooperative game theory and the research field concerning climate change dynamics. New results are obtained in the framework of competitive bargaining solutions and related issues, moving from a cooperative approach to a competitive one. Furthermore, the dynamics of balanced and super-balanced games are exposed, with particular reference to coalitions. Some open problems are presented to aid future research in this area.

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