Using foraging ecology to elucidate the role of species interactions in two contrasting mixed-species flock systems in northeastern Peru

2016 ◽  
Vol 128 (2) ◽  
pp. 378 ◽  
Author(s):  
Ari E. Martínez ◽  
Scott K. Robinson
Keyword(s):  
Species Interactions ◽  
Foraging Ecology ◽  
Species Flock ◽  
Mixed Species

scholarly journals Influence of the Electrolyte Salt Concentration on DNA Detection with Graphene Transistors

Biosensors ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 24
Author(s):  
Agnes Purwidyantri ◽  
Telma Domingues ◽  
Jérôme Borme ◽  
Joana Rafaela Guerreiro ◽  
Andrey Ipatov ◽  
...  
Keyword(s):  
Phosphate Buffer ◽  
Species Interactions ◽  
Field Effect ◽  
Field Effect Transistors ◽  
Limit Of Detection ◽  
Debye Length ◽  
Intermolecular Forces ◽  
Single Layer Graphene ◽  
Dna Adsorption

Liquid-gated Graphene Field-Effect Transistors (GFET) are ultrasensitive bio-detection platforms carrying out the graphene’s exceptional intrinsic functionalities. Buffer and dilution factor are prevalent strategies towards the optimum performance of the GFETs. However, beyond the Debye length (λD), the role of the graphene-electrolytes’ ionic species interactions on the DNA behavior at the nanoscale interface is complicated. We studied the characteristics of the GFETs under different ionic strength, pH, and electrolyte type, e.g., phosphate buffer (PB), and phosphate buffer saline (PBS), in an automatic portable built-in system. The electrostatic gating and charge transfer phenomena were inferred from the field-effect measurements of the Dirac point position in single-layer graphene (SLG) transistors transfer curves. Results denote that λD is not the main factor governing the effective nanoscale screening environment. We observed that the longer λD was not the determining characteristic for sensitivity increment and limit of detection (LoD) as demonstrated by different types and ionic strengths of measuring buffers. In the DNA hybridization study, our findings show the role of the additional salts present in PBS, as compared to PB, in increasing graphene electron mobility, electrostatic shielding, intermolecular forces and DNA adsorption kinetics leading to an improved sensitivity.

scholarly journals Is Intestinal Bacterial Diversity Enhanced by Trans-Species Spread in the Mixed-Species Flock of Hooded Crane (Grus monacha) and Bean Goose (Anser fabalis) Wintering in the Lower and Middle Yangtze River Floodplain?

Animals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 233
Author(s):  
Zhuqing Yang ◽  
Lizhi Zhou
Keyword(s):  
Contact Time ◽  
Alpha Diversity ◽  
Gut Bacteria ◽  
Species Flock ◽  
Mixed Species ◽  
Microbial Composition ◽  
Indirect Contact ◽  
Hooded Crane ◽  
Bean Goose ◽  
Intestinal Pathogens

Diversity of gut microbes is influenced by many aspects, including the host internal factors and even direct or indirect contact with other birds, which is particularly important for mixed-species wintering waterbird flocks. In this study, Illumina high-throughput sequencing was used to analyze the intestinal bacteria of the hooded crane and bean goose whose niches overlap at Shengjin Lake. We tested whether contact time enhances the trans-species spread of gut bacteria. Results indicate alpha-diversity and microbial composition displayed significant separation between the two hosts in every wintering period, although the number of bacteria types shared increased with increasing contact time. For the same species, with the lengthening of contact time, alpha-diversity and the number of operational taxonomic units (OTUs) in the host intestine augmented, and the common OTUs and structural similarity of microflora in the middle and late periods were more than in the early and middle periods. In addition, we found a very high proportion of shared pathogens. Our results indicate that, although intestinal microflora of different species were separated, direct or indirect contact in the mixed-species flock caused the spread of gut bacteria trans-species, indicating that more attention should be paid to intestinal pathogens in wild birds.

scholarly journals Testing the spatial and temporal framework of speciation in an ancient lake species flock: the leech genus <i>Dina</i> (Hirudinea: Erpobdellidae) in Lake Ohrid

2010 ◽  
Vol 7 (11) ◽  
pp. 3387-3402 ◽  
Author(s):  
S. Trajanovski ◽  
C. Albrecht ◽  
K. Schreiber ◽  
R. Schultheiß ◽  
T. Stadler ◽  
...  
Keyword(s):  
Molecular Clock ◽  
Abiotic Factors ◽  
Time Frame ◽  
Recent Common Ancestor ◽  
Species Flock ◽  
Ancient Lake ◽  
Lake Ohrid ◽  
Most Recent Common Ancestor ◽  
Extant Species

Abstract. Ancient Lake Ohrid on the Balkan Peninsula is considered to be the oldest ancient lake in Europe with a suggested Plio-/Pleistocene age. Its exact geological age, however, remains unknown. Therefore, molecular clock data of Lake Ohrid biota may serve as an independent constraint of available geological data, and may thus help to refine age estimates. Such evolutionary data may also help unravel potential biotic and abiotic factors that promote speciation events. Here, mitochondrial sequencing data of one of the largest groups of endemic taxa in the Ohrid watershed, the leech genus Dina, is used to test whether it represents an ancient lake species flock, to study the role of potential horizontal and vertical barriers in the watershed for evolutionary events, to estimate the onset of diversification in this group based on molecular clock analyses, and to compare this data with data from other endemic species for providing an approximate time frame for the origin of Lake Ohrid. Based on the criteria speciosity, monophyly and endemicity, it can be concluded that Dina spp. from the Ohrid watershed, indeed, represents an ancient lake species flock. Lineage sorting of its species, however, does not seem to be complete and/or hybridization may occur. Analyses of population structures of Dina spp. in the Ohrid watershed indicate a horizontal zonation of haplotypes from spring and lake populations, corroborating the role of lake-side springs, particularly the southern feeder springs, for evolutionary processes in endemic Ohrid taxa. Vertical differentiation of lake taxa, however, appears to be limited, though differences between populations from the littoral and the profundal are apparent. Molecular clock analyses indicate that the most recent common ancestor of extant species of this flock is approximately 1.99 ± 0.83 million years (Ma) old, whereas the split of the Ohrid Dina flock from a potential sister taxon outside the lake is estimated at 8.30 ± 3.60 Ma. Comparisons with other groups of endemic Ohrid species indicated that in all cases, diversification within the watershed started ≤2 Ma ago. Thus, this estimate may provide information on a minimum age for the origin of Lake Ohrid. Maximum ages are less consistent and generally less reliable. But cautiously, a maximum age of 3 Ma is suggested. Interestingly, this time frame of approximately 2–3 Ma ago for the origin of Lake Ohrid, generated based on genetic data, well fits the time frame most often used in the literature by geologists.

scholarly journals Testing the spatial and temporal framework of speciation in an ancient lake species flock: the leech genus <i>Dina</i> (Hirudinea: Erpobdellidae) in Lake Ohrid

2010 ◽  
Vol 7 (4) ◽  
pp. 5011-5045 ◽  
Author(s):  
S. Trajanovski ◽  
C. Albrecht ◽  
K. Schreiber ◽  
R. Schultheiß ◽  
T. Stadler ◽  
...  
Keyword(s):  
Molecular Clock ◽  
Abiotic Factors ◽  
Time Frame ◽  
Recent Common Ancestor ◽  
Species Flock ◽  
Ancient Lake ◽  
Lake Ohrid ◽  
Most Recent Common Ancestor ◽  
Extant Species

Abstract. Ancient Lake Ohrid on the Balkan Peninsula is considered to be the oldest ancient lake in Europe with a suggested Plio-Pleistocene age. Its exact geological age, however, remains unknown. Therefore, molecular clock data of Lake Ohrid biota may serve as an independent constraint of available geological data, and may thus also help to refine age estimates. Such evolutionary data may also help unravel potential biotic and abiotic factors that promote speciation events. Here, mitochondrial sequencing data of one of the largest groups of endemic taxa in Lake Ohrid, the leech genus Dina, is used to test whether it represents an ancient lake species flock, to study the role of horizontal and vertical barriers in Lake Ohrid for evolutionary events, to estimate the onset of intralacustrine diversification in this group based on molecular clock analyses, and to compare this data with data from other endemic species for providing an approximate time frame for the origin of Lake Ohrid. Based on the criteria speciosity, monophyly and endemicity, it can be concluded that Lake Ohrid Dina, indeed, represents an ancient lake species flock. Lineage sorting of its species, however, does not seem to be complete. Analyses of population structures of Dina spp. in the Ohrid watershed indicate a horizontal zonation of haplotypes from spring and lake populations, corroborating the role of lake-side springs, particularly the southern feeder springs, for evolutionary processes in endemic Ohrid taxa. Vertical differentiation of lake taxa, however, appears to be limited, though differences between populations from the littoral and the profundal are apparent. Molecular clock analyses indicate that the most recent common ancestor of extant species of this flock is approximately 1.99±0.83 Ma old, whereas the split of the Lake Ohrid Dina flock from a potential sister taxon outside the lake is estimated at 8.30±3.60 Ma. Comparisons with other groups of endemic Ohrid species indicated that in all cases, intralacustrine diversification started ≤2 Ma ago. Thus, this estimate may provide information on a minimum age for the origin of Lake Ohrid. Maximum ages are less consistent and generally less reliable. But cautiously, a maximum age of 3 Ma is suggested. Interestingly, this time frame of approximately 2–3 Ma for the origin of Lake Ohrid, generated based solely on evolutionary data, well fits the time frame most often used in the literature by geologists. Future studies must show whether this concurrence holds true.

Context-specific behavior serves as a mechanism of interspecific cohesion in mixed-species flocks

The Auk ◽  
2021 ◽  
Author(s):  
Sean M Williams ◽  
Catherine A Lindell
Keyword(s):  
Flight Distance ◽  
Species Flock ◽  
Mixed Species ◽  
Specific Behavior ◽  
Call Type ◽  
Interspecific Associations ◽  
Mixed Species Flocks ◽  
Context Specific ◽  
Species Flocks

Abstract We investigated whether context-specific behavior is responsible for the cohesion of mixed-species flocks of antshrikes and antwrens in Amazonian Peru. Antshrikes perform a behavior while spatially repositioning, to which antwrens respond by approaching. The cohesion of interspecific associations requires communication, although the mechanisms often are unexplored. In monospecific groups, cohesion among individuals is maintained with actions or vocalizations given in a certain context. Dusky-throated Antshrikes (Thamnomanes ardesiacus) vocalize while in flight and the number of times they vocalize covaries with the flight distance. We refer to this pairing of flight and vocalization as repositioning behavior. Furthermore, antshrikes pair a different call type with perching, which we refer to as perching behavior. We followed Long-winged (Myrmotherula longipennis) and White-flanked Antwrens (M. axillaris) and recorded their response following natural vocalizations (no playback used) given by the antshrikes. Long-winged Antwrens, but not White-flanked, flew toward an antshrike significantly sooner and were more likely to approach the antshrikes after the repositioning behavior than after perching behavior. In addition, Long-winged Antwrens, but not White-flanked, flew toward an antshrike sooner after a longer series of repositioning calls than after a shorter series. We did not distinguish between the Long-winged Antwrens’ response as a function of movement vs. vocalizations of the antshrikes, although we argue that vocalizations are likely a more important communication component of repositioning behavior than movement. It remains unclear whether the antshrikes are deliberately signaling the Long-winged Antwrens or the antwrens are taking advantage of the repositioning behavior; active signaling is possible since antshrikes benefit from antwrens. White-flanked Antwrens may be less responsive to the antshrikes since they have a lower propensity to occur in a mixed-species flock. The results indicate that the repositioning behavior of Dusky-throated Antshrikes is a key mechanism of interspecific cohesion of Amazonian mixed-species flocks of the understory.

scholarly journals Interactions between Climate and Nutrient Cycles on Forest Response to Global Change: The Role of Mixed Forests

Forests ◽  
2019 ◽  
Vol 10 (8) ◽  
pp. 609 ◽  
Author(s):  
Ester González de Andrés
Keyword(s):  
Climate Change ◽  
Global Change ◽  
Environmental Conditions ◽  
Species Interactions ◽  
N Deposition ◽  
Elemental Ratios ◽  
Nutrient Mineralization ◽  
Carbon Dioxide Co2 ◽  
The Impact

Forest ecosystems are undergoing unprecedented changes in environmental conditions due to global change impacts. Modification of global biogeochemical cycles of carbon and nitrogen, and the subsequent climate change are affecting forest functions at different scales, from physiology and growth of individual trees to cycling of nutrients. This review summarizes the present knowledge regarding the impact of global change on forest functioning not only with respect to climate change, which is the focus of most studies, but also the influence of altered nitrogen cycle and the interactions among them. The carbon dioxide (CO2) fertilization effect on tree growth is expected to be constrained by nutrient imbalances resulting from high N deposition rates and the counteractive effect of increasing water deficit, which interact in a complex way. At the community level, responses to global change are modified by species interactions that may lead to competition for resources and/or relaxation due to facilitation and resource partitioning processes. Thus, some species mixtures can be more resistant to drought than their respective pure forests, albeit it depends on environmental conditions and species’ functional traits. Climate change and nitrogen deposition have additional impacts on litterfall dynamics, and subsequent decomposition and nutrient mineralization processes. Elemental ratios (i.e., stoichiometry) are associated with important ecosystem traits, including trees’ adaptability to stress or decomposition rates. As stoichiometry of different ecosystem components are also influenced by global change, nutrient cycling in forests will be altered too. Therefore, a re-assessment of traditional forest management is needed in order to cope with global change. Proposed silvicultural systems emphasize the key role of diversity to assure multiple ecosystem services, and special attention has been paid to mixed-species forests. Finally, a summary of the patterns and underlying mechanisms governing the relationships between diversity and different ecosystems functions, such as productivity and stability, is provided.

Ecological Interactions and Macroevolution: A New Field with Old Roots

2020 ◽  
Vol 51 (1) ◽  
pp. 215-243 ◽  
Author(s):  
David H. Hembry ◽  
Marjorie G. Weber
Keyword(s):  
Species Interactions ◽  
Interspecific Interactions ◽  
Biotic Interactions ◽  
Evolutionary Change ◽  
Future Research ◽  
Ecological Interactions ◽  
Open Questions ◽  
Work Done ◽  
Lineage Diversification

Linking interspecific interactions (e.g., mutualism, competition, predation, parasitism) to macroevolution (evolutionary change on deep timescales) is a key goal in biology. The role of species interactions in shaping macroevolutionary trajectories has been studied for centuries and remains a cutting-edge topic of current research. However, despite its deep historical roots, classic and current approaches to this topic are highly diverse. Here, we combine historical and contemporary perspectives on the study of ecological interactions in macroevolution, synthesizing ideas across eras to build a zoomed-out picture of the big questions at the nexus of ecology and macroevolution. We discuss the trajectory of this important and challenging field, dividing research into work done before the 1970s, research between 1970 and 2005, and work done since 2005. We argue that in response to long-standing questions in paleobiology, evidence accumulated to date has demonstrated that biotic interactions (including mutualism) can influence lineage diversification and trait evolution over macroevolutionary timescales, and we outline major open questions for future research in the field.

scholarly journals Coexistence of surface and cave amphipods in an ecotone environment

2011 ◽  
Vol 80 (2) ◽  
pp. 133-141 ◽  
Author(s):  
Roman Luštrik ◽  
Martin Turjak ◽  
Simona Kralj-Fišer ◽  
Cene Fišer
Keyword(s):  
Leaf Litter ◽  
Species Interactions ◽  
Interspecific Interactions ◽  
Habitat Choice ◽  
Intraspecific Interactions ◽  
Size Dependent ◽  
Predation Effects ◽  
Similar Body ◽  
Subterranean Species

Interspecific interactions between surface and subterranean species may be a key determinant for species distributions. Until now, the existence of competition (including predation) between these groups has not been tested. To assess the coexistence and potential role of interspecific interactions between surface Gammarus fossarum and subterranean Niphargus timavi, and to determine their micro distributions, we conducted a series of field and laboratory observations. We aimed to determine: (1) species substrate preference, (2) whether the presence of G. fossarum influences the habitat choice of N. timavi, and (3) possible predation effects on micro habitat choice of small juveniles. Throughout a small river in SW Slovenia, N. timavi was predominantly found in leaf litter and gravel, but rarely in sand. In the sand however, we exclusively found juveniles. In contrast, surface G. fossarum sheltered mainly in leaf litter. A similar, body size dependent, micro distribution was observed in G. fossarum, where small individuals were generally found in gravel and sand. The presence of G. fossarum affected the micro distribution of juvenile, but not adult, N. timavi. In the laboratory we observed predation and cannibalism in both species. Niphargus timavi, however, appeared to be a more efficient predator than G. fossarum. In particular, juvenile N. timavi were most vulnerable to preying by adults of both species. This probably affected the distribution of juvenile N. timavi that chose finer substrates when placed with adult individuals in an aquarium with granules of different size. To understand the distribution of subterranean species, the summed effect of intraspecific interactions, as well as surface – subterranean species interactions, in particular between individuals of different size, should be taken into account.

scholarly journals Evaluating insect-host interactions as a driver of species divergence in palm flower weevils

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Bruno A. S. de Medeiros ◽  
Brian D. Farrell
Keyword(s):  
Species Interactions ◽  
Population Divergence ◽  
Insect Host ◽  
Flower Visitors ◽  
Host Interactions ◽  
Isolation By Environment ◽  
Insect Populations ◽  
Evolutionary Consequences ◽  
Antagonistic Interactions

AbstractPlants and their specialized flower visitors provide valuable insights into the evolutionary consequences of species interactions. In particular, antagonistic interactions between insects and plants have often been invoked as a major driver of diversification. Here we use a tropical community of palms and their specialized insect flower visitors to test whether antagonisms lead to higher population divergence. Interactions between palms and the insects visiting their flowers range from brood pollination to florivory and commensalism, with the latter being species that feed on decaying–and presumably undefended–plant tissues. We test the role of insect-host interactions in the early stages of diversification of nine species of beetles sharing host plants and geographical ranges by first delimiting cryptic species and then using models of genetic isolation by environment. The degree to which insect populations are structured by the genetic divergence of plant populations varies. A hierarchical model reveals that this variation is largely uncorrelated with the kind of interaction, showing that antagonistic interactions are not associated with higher genetic differentiation. Other aspects of host use that affect plant-associated insects regardless of the outcomes of their interactions, such as sensory biases, are likely more general drivers of insect population divergence.

Sign in / Sign up

Export Citation Format

Share Document