21 research outputs found
Kin-Aggregations Explain Chaotic Genetic Patchiness, a Commonly Observed Genetic Pattern, in a Marine Fish
The phenomenon of chaotic genetic patchiness is a pattern commonly seen in marine organisms, particularly those with demersal adults and pelagic larvae. This pattern is usually associated with sweepstakes recruitment and variable reproductive success. Here we investigate the biological underpinnings of this pattern in a species of marine goby Coryphopterus personatus. We find that populations of this species show tell-tale signs of chaotic genetic patchiness including: small, but significant, differences in genetic structure over short distances; a non-equilibrium or “chaotic” pattern of differentiation among locations in space; and within locus, within population deviations from the expectations of Hardy-Weinberg equilibrium (HWE). We show that despite having a pelagic larval stage, and a wide distribution across Caribbean coral reefs, this species forms groups of highly related individuals at small spatial scales (metres). These spatially clustered family groups cause the observed deviations from HWE and local population differentiation, a finding that is rarely demonstrated, but could be more common than previously thought
Ion-Collision Emission Excitation Cross Sections for Xenon Electric Thruster Plasmas
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76738/1/AIAA-33657-821.pd
Class dynamics of development: a methodological note
This article argues that class relations are constitutive of developmental processes and central to understanding inequality within and between countries. In doing so it illustrates and explains the diversity of the actually existing forms of class relations, and the ways in which they interplay with other social relations such as gender and ethnicity. This is part of a wider project to re- vitalise class analysis in the study of development problems and experiences
Building a tuberculosis-free world: The Lancet Commission on tuberculosis
___Key messages___
The Commission recommends five priority investments to achieve a tuberculosis-free world within a generation. These investments are designed to fulfil the mandate of the UN High Level Meeting on tuberculosis. In addition, they answer
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Determine the effect of variability in habitat quality on dispersal
The dispersal of individuals between populations is a foundational process to understand at the interface of ecology and evolution. The natal habitat is theorized to strongly influence the degree of dispersal expected. However, understanding the interaction between habitat and dispersal is difficult to study empirically, particularly in a single location where other environmental factors are held constant. Understanding how habitats influence dispersal is important not only for the foundational understanding of ecological and evolutionary processes but also as they relate to the design of marine protected area networks. Here I seek to understand how heterogeneity in habitat quality influences the dispersal dynamics of the common Caribbean reef goby Coryphopterus hyalinus as a model for other species with similar life histories in different systems. To determine how variation in habitat quality influences dispersal first I had to establish what topographical features of the reef equate to greater habitat quality from the perspective of the previously presumed habitat generalist C. hyalinus. I found that as adults C. hyalinus live in mixed species shoals with their congener C. personatus and are distributed across shallow coral reef ecosystems tending to be found in greater densities in more complex, deeper reef areas at the margin of large sand patches. In Turneffe Atoll, C. hyalinus has an average dispersal distance of 3.1 ± 0.3 km with 95% of individuals dispersing less than 7.7 ± 0.65 km. However, spatially heterogeneous habitats are characterized by shorter mean dispersal distances, smaller dispersal spreads, and higher propensity for long-distance dispersal events. This observation likely has strong conservation implications for the design and futureproofing of network-based conservation designs which depend upon dispersal between individual nodes of the network for proper functioning. As anthropogenic climate change alters habitats and in the short-term leads to increasingly fragmented and heterogeneous landscapes these networks may no longer be sustainable given the shrinking of the dispersal spread of the species these networks are designed to protect.Life SciencesCollege of Science and Engineerin
Distributed under Creative Commons CC-BY 4.0 Effectiveness of removals of the invasive lionfish: how many dives are needed to deplete a reef?
ABSTRACT Introduced Indo-Pacific red lionfish (Pterois volitans/miles) have spread throughout the greater Caribbean and are associated with a number of negative impacts on reef ecosystems. Human interventions, in the form of culling activities, are becoming common to reduce their numbers and mitigate the negative effects associated with the invasion. However, marine managers must often decide how to best allocate limited resources. Previous work has identified the population size thresholds needed to limit the negative impacts of lionfish. Here we develop a framework that allows managers to predict the removal effort required to achieve specific targets (represented as the percent of lionfish remaining on the reef). We found an important trade-off between time spent removing and achieving an increasingly smaller lionfish density. The model used in our suggested framework requires relatively little data to parameterize, allowing its use with already existing data, permitting managers to tailor their culling strategy to maximize efficiency and rate of success. Subjects Ecology, Marine Biolog
Effectiveness of removals of the invasive lionfish: how many dives are needed to deplete a reef?
Introduced Indo-Pacific red lionfish (Pterois volitans/miles) have spread throughout the greater Caribbean and are associated with a number of negative impacts on reef ecosystems. Human interventions, in the form of culling activities, are becoming common to reduce their numbers and mitigate the negative effects associated with the invasion. However, marine managers must often decide how to best allocate limited resources. Previous work has identified the population size thresholds needed to limit the negative impacts of lionfish. Here we develop a framework that allows managers to predict the removal effort required to achieve specific targets (represented as the percent of lionfish remaining on the reef). We found an important trade-off between time spent removing and achieving an increasingly smaller lionfish density. The model used in our suggested framework requires relatively little data to parameterize, allowing its use with already existing data, permitting managers to tailor their culling strategy to maximize efficiency and rate of success