scholarly journals A test of altitude-related variation in aerobic metabolism of Andean birds

2020 ◽  
Author(s):  
Natalia Gutierrez-Pinto ◽  
Gustavo A. Londoño ◽  
Mark A. Chappell ◽  
Jay F. Storz
Keyword(s):  
Related Species ◽  
Aerobic Metabolism ◽  
Metabolic Rates ◽  
Aerobic Scope ◽  
Closely Related Species ◽  
Related Variation ◽  
Species Pairs ◽  
Aerobic Exercise Capacity ◽  
Summary Statement ◽  
Broad Scale

AbstractEndotherms at high altitude face the combined challenges of cold and hypoxia. Cold increases thermoregulatory costs, and hypoxia may limit both thermogenesis and aerobic exercise capacity. Consequently, in comparisons between closely related highland and lowland taxa, we might expect to observe consistent differences in basal metabolism (BMR), maximal metabolism (MMR), and aerobic scope. Broad-scale comparative studies of birds reveal no association between BMR and native elevation, and altitude effects on MMR have not been investigated. We tested for altitude-related variation in aerobic metabolism in 10 Andean passerines representing five pairs of closely related species with contrasting elevational ranges. Mass-corrected BMR and MMR were significantly higher in most highland species relative to their lowland counterparts, but there was no uniform elevational trend across all pairs of species.Summary statementWe tested for altitude-related variation in aerobic metabolism in species pairs with contrasting elevational ranges. Metabolic rates were significantly higher in most highland species but there was no uniform elevational trend.

scholarly journals A test of altitude-related variation in aerobic metabolism of Andean birds

2021 ◽  
Author(s):  
Gutierrez-Pinto Natalia ◽  
Gustavo A. Londoño ◽  
Mark A. Chappell ◽  
Jay F. Storz
Keyword(s):  
Related Species ◽  
Comparative Studies ◽  
Aerobic Metabolism ◽  
Simple Explanation ◽  
Aerobic Scope ◽  
Closely Related Species ◽  
Related Variation ◽  
Aerobic Exercise Capacity ◽  
Elevational Variation ◽  
Broad Scale

Endotherms at high altitude face the combined challenges of cold and hypoxia. Cold increases thermoregulatory costs, and hypoxia may limit both thermogenesis and aerobic exercise capacity. Consequently, in comparisons between closely related highland and lowland taxa, we might expect to observe consistent differences in basal metabolism (BMR), maximal metabolism (MMR), and aerobic scope. Broad-scale comparative studies of birds reveal no association between BMR and native elevation, and altitude effects on MMR have not been investigated. We tested for altitude-related variation in aerobic metabolism in 10 Andean passerines representing five pairs of closely related species with contrasting elevational ranges. Mass-corrected BMR and MMR were significantly higher in most highland species relative to their lowland counterparts, but there was no uniform elevational trend across all pairs of species. Our results suggest that there is no simple explanation regarding the ecological and physiological causes of elevational variation in aerobic metabolism.

Phenological displacement is uncommon among sympatric angiosperms

2020 ◽  
Author(s):  
Daniel S. Park ◽  
Ian K. Breckheimer ◽  
Aaron M. Ellison ◽  
Goia M. Lyra ◽  
Charles C. Davis
Keyword(s):  
Flowering Time ◽  
Related Species ◽  
Species Interactions ◽  
Spatial Scales ◽  
Character Displacement ◽  
Future Climate Change ◽  
Herbarium Specimens ◽  
Reproductive Character Displacement ◽  
Closely Related Species ◽  
Species Pairs

AbstractInteractions between species can influence access to resources and successful reproduction. One possible outcome of such interactions is reproductive character displacement. Here, the similarity of reproductive traits – such as flowering time – among close relatives growing in sympatry differ more so than when growing apart. However, evidence for the overall prevalence and direction of this phenomenon, or the stability of such differences under environmental change, remains untested across large taxonomic and spatial scales. We apply data from tens of thousands of herbarium specimens to examine character displacement in flowering time across 110 animal-pollinated angiosperm species in the eastern USA. We demonstrate that the degree and direction of phenological displacement among co-occurring closely related species pairs varies tremendously. Overall, flowering time displacement in sympatry is not common. However, displacement is generally greater among species pairs that flower close in time, regardless of direction. We additionally identify that future climate change may alter the nature of phenological displacement among many of these species pairs. On average, flowering times of closely related species were predicted to shift further apart by the mid-21st century, which may have significant future consequences for species interactions and gene flow.

scholarly journals Genomic compatibility occurs over a wide range of parental genetic similarity in an outcrossing plant

2005 ◽  
Vol 272 (1570) ◽  
pp. 1333-1338 ◽  
Author(s):  
Yvonne Willi ◽  
Josh Van Buskirk
Keyword(s):  
Mate Choice ◽  
Inbreeding Depression ◽  
Related Species ◽  
Genetic Similarity ◽  
Mating Systems ◽  
Hybrid Breakdown ◽  
Offspring Performance ◽  
Closely Related Species ◽  
Wide Range ◽  
Broad Scale

The theory of inbreeding and outbreeding suggests that there is a hump-shaped relationship between the genetic similarity of sexually reproducing parents and the performance of their offspring. Inbreeding depression occurs when genetic similarity is high, whereas hybrid breakdown is expected when genetic similarity is low. Between these extremes, the effect of genetic similarity on fitness is unclear. We studied the shape of this relationship by crossing 65 target genotypes of the clonal, self-incompatible Ranunculus reptans with partner genotypes spanning a broad scale of genetic similarity, ranging from crosses within populations to between-population crosses and hybridisation with a closely related species. Offspring were raised in outdoor tubs. Results revealed a quadratic relationship between parental genetic distance and offspring performance, with the clonal component of fitness more strongly hump-shaped than the sexual component. Optimal genetic similarity encompassed a broad range of within-population and between-population crosses. This pattern of genomic compatibility has important implications for the evolution of mating systems and mate choice.

scholarly journals The outcomes of most aggressive interactions among closely related bird species are asymmetric

2016 ◽  
Author(s):  
Paul R Martin ◽  
Cameron Freshwater ◽  
Cameron K Ghalambor
Keyword(s):  
Related Species ◽  
Selective Pressure ◽  
Statistical Tests ◽  
Bird Species ◽  
Evolutionary Strategies ◽  
Published Data ◽  
Closely Related Species ◽  
Aggressive Interactions ◽  
Species Pairs ◽  
Using Data

Aggressive interactions among closely related species are common. These can play an important role as a selective pressure shaping species, traits and assemblages. The nature of this selective pressure depends on whether the outcomes of aggressive contests are asymmetric between species (i.e., one species is consistently dominant), yet few studies have estimated the prevalence of asymmetric versus symmetric outcomes to aggressive contests. Here we use previously published data involving 26,656 interactions between 270 species pairs of birds from 26 taxonomic families to address the question: How often are aggressive interactions among closely related bird species asymmetric? We define asymmetry using (i) the proportion of contests won by one species, and (ii) statistical tests for asymmetric outcomes of aggressive contests. We calculate these asymmetries using data summed across different sites for each species pair, and compare results to asymmetries calculated using data separated by location. We find that 80% of species pairs had aggressive outcomes where one species won 80% or more of aggressive contests. We also find that the majority of aggressive interactions among closely related species show statistically significant asymmetries, and above a sample size of 52 interactions, all outcomes are asymmetric following binomial tests. Results using data partitioned by location showed similar patterns. Species pairs with dominance data from multiple sites showed the same dominance relationship across locations in 93% of the species pairs. Overall, our results suggest that the outcome of aggressive interactions among closely related species are usually consistent and asymmetric, and should thus favor ecological and evolutionary strategies specific to the position of a species within a dominance hierarchy.

scholarly journals The outcomes of most aggressive interactions among closely related bird species are asymmetric

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e2847 ◽  
Author(s):  
Paul R. Martin ◽  
Cameron Freshwater ◽  
Cameron K. Ghalambor
Keyword(s):  
Related Species ◽  
Selective Pressure ◽  
Statistical Tests ◽  
Bird Species ◽  
Evolutionary Strategies ◽  
Published Data ◽  
Closely Related Species ◽  
Aggressive Interactions ◽  
Species Pairs ◽  
Using Data

Aggressive interactions among closely related species are common, and can play an important role as a selective pressure shaping species traits and assemblages. The nature of this selective pressure depends on whether the outcomes of aggressive contests are asymmetric between species (i.e., one species is consistently dominant), yet few studies have estimated the prevalence of asymmetric versus symmetric outcomes to aggressive contests. Here we use previously published data involving 26,212 interactions between 270 species pairs of birds from 26 taxonomic families to address the question: How often are aggressive interactions among closely related bird species asymmetric? We define asymmetry using (i) the proportion of contests won by one species, and (ii) statistical tests for asymmetric outcomes of aggressive contests. We calculate these asymmetries using data summed across different sites for each species pair, and compare results to asymmetries calculated using data separated by location. We find that 80% of species pairs had aggressive outcomes where one species won 80% or more of aggressive contests. We also find that the majority of aggressive interactions among closely related species show statistically significant asymmetries, and above a sample size of 52 interactions, all outcomes are asymmetric following binomial tests. Species pairs with dominance data from multiple sites showed the same dominance relationship across locations in 93% of the species pairs. Overall, our results suggest that the outcome of aggressive interactions among closely related species are usually consistent and asymmetric, and should thus favor ecological and evolutionary strategies specific to the position of a species within a dominance hierarchy.

scholarly journals The outcomes of most aggressive interactions among closely related bird species are asymmetric

2016 ◽  
Author(s):  
Paul R Martin ◽  
Cameron Freshwater ◽  
Cameron K Ghalambor
Keyword(s):  
Related Species ◽  
Selective Pressure ◽  
Statistical Tests ◽  
Bird Species ◽  
Evolutionary Strategies ◽  
Published Data ◽  
Closely Related Species ◽  
Aggressive Interactions ◽  
Species Pairs ◽  
Using Data

Aggressive interactions among closely related species are common. These can play an important role as a selective pressure shaping species, traits and assemblages. The nature of this selective pressure depends on whether the outcomes of aggressive contests are asymmetric between species (i.e., one species is consistently dominant), yet few studies have estimated the prevalence of asymmetric versus symmetric outcomes to aggressive contests. Here we use previously published data involving 26,656 interactions between 270 species pairs of birds from 26 taxonomic families to address the question: How often are aggressive interactions among closely related bird species asymmetric? We define asymmetry using (i) the proportion of contests won by one species, and (ii) statistical tests for asymmetric outcomes of aggressive contests. We calculate these asymmetries using data summed across different sites for each species pair, and compare results to asymmetries calculated using data separated by location. We find that 80% of species pairs had aggressive outcomes where one species won 80% or more of aggressive contests. We also find that the majority of aggressive interactions among closely related species show statistically significant asymmetries, and above a sample size of 52 interactions, all outcomes are asymmetric following binomial tests. Results using data partitioned by location showed similar patterns. Species pairs with dominance data from multiple sites showed the same dominance relationship across locations in 93% of the species pairs. Overall, our results suggest that the outcome of aggressive interactions among closely related species are usually consistent and asymmetric, and should thus favor ecological and evolutionary strategies specific to the position of a species within a dominance hierarchy.

scholarly journals Variation of foliar silicon concentrations in temperate forbs: effects of soil silicon, phylogeny and habitat

Oecologia ◽  
2021 ◽  
Author(s):  
Marius Klotz ◽  
Jörg Schaller ◽  
Susanne Kurze ◽  
Bettina M. J. Engelbrecht
Keyword(s):  
Intraspecific Variation ◽  
Related Species ◽  
Phylogenetic Signal ◽  
Interspecific Variation ◽  
Temperate Grasslands ◽  
Ecological Consequences ◽  
Closely Related Species ◽  
Abiotic Stressors ◽  
Species Pairs ◽  
Dicotyledonous Plants

AbstractSilicon (Si) accumulation is known to alleviate various biotic and abiotic stressors in plants with potential ecological consequences. However, for dicotyledonous plants our understanding of Si variation remains limited. We conducted a comparative experimental study to investigate (1) interspecific variation of foliar Si concentrations across 37 dicotyledonous forbs of temperate grasslands, (2) intraspecific variation in foliar Si concentration in response to soil Si availability, the influence of (3) phylogenetic relatedness, and (4) habitat association to moisture. Foliar Si differed markedly (approx. 70-fold) across the investigated forbs, with some species exhibiting Si accumulation similar to grasses. Foliar Si increased with soil Si availability, but the response varied across species: species with higher Si accumulation capacity showed a stronger response, indicating that they did not actively upregulate Si uptake under low soil Si availability. Foliar Si showed a pronounced phylogenetic signal, i.e., closely related species exhibited more similar foliar Si concentrations than distantly related species. Significant differences in foliar Si concentration within closely related species pairs nevertheless support that active Si uptake and associated high Si concentrations has evolved multiple times in forbs. Foliar Si was not higher in species associated with drier habitats, implying that in dicotyledonous forbs of temperate grasslands high foliar Si is not an adaptive trait to withstand drought. Our results demonstrated considerable inter- and intraspecific variation in foliar Si concentration in temperate forbs. This variation should have pervasive, but so far understudied, ecological consequences for community composition and functioning of temperate grasslands under land-use and climate change.

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