Interrelationships of Fishes of the Order Stomiiformes

The order Stomiiformes (Vertebrata: Actinopterygii) is composed of 417 of deep open ocean fishes, including some of the most abundant vertebrates on earth. The monophyly of the order is well established morphologically, but its phylogenetic position relative to other fishes is not certain. While the prevailing view is that Stomiiformes is the basal neoteleost taxon, sister to Eurypterygii, some authors have placed the group in a clade with the osmeroid and galaxioid fishes. Furthermore, the relationships within the Stomiiformes are poorly understood, and much of the existing classification is suspected not to reflect natural groups. Previous attempts to understand the relationships of stomiiform fishes have been complicated by the extensive morphological homoplasy within the group. The present study is based on DNA sequence data from the nuclear and mitochondrial genomes and examines the phylogenetic position of Stomiiformes as well as the relationships within the group. The phylogeny is reconstructed using the parsimony and maximum likelihood criteria, and via Bayesian inference. The relationships recovered via all three methods are similar. Stomiiformes is recovered in a clade with osmeroids and galaxioids, not as the basal neoteleost group. Furthermore, the relationships recovered within the group contradict much of the existing classification

Family support in practice : voices from the field

This paper revisits core family support messages for social work practice in working with children and families, linking to findings from high-profile child protection cases in the UK and the Republic of Ireland. Drawing on a comparative study where these identified practice messages were explored through the lens of testimony of family support workers in the UK and Ireland, these core messages are examined. Operating with hard-to-engage children and parents, we hear how families and family support worker colleagues now view the core functions of child and family work across both jurisdictions (Ireland and England). The authors argue that by naming a more detailed set of practices that are deemed as most useful by families, based on the benefits and challenges of intensive family support work, key messages arise that have major resonance for social work and multiagency practice into the future. A basic message from this study is that valuable lessons on engagement and intervention with families can be drawn for professionals by examining the practice elements of this group of paraprofessionals in the child and family arena. This paper adds to debates on the role of support and intervention in social work and family support work

Validity of threshold-crossing analysis of symbolic dynamics from chaotic time series

A practical and popular technique to extract the symbolic dynamics from experimentally measured chaotic time series is the threshold-crossing method, by which an arbitrary partition is utilized for determining the symbols. We address to what extent the symbolic dynamics so obtained can faithfully represent the phase-space dynamics. Our principal result is that such practice leads to a severe misrepresentation of the dynamical system. The measured topological entropy is a Devil's staircase-like, but surprisingly nonmonotone, function of a parameter characterizing the amount of misplacement of the partition.Comment: 8 pages + 4 figures in .pd

A Tale of Four “Carp”: Invasion Potential and Ecological Niche Modeling

. We assessed the geographic potential of four Eurasian cyprinid fishes (common carp, tench, grass carp, black carp) as invaders in North America via ecological niche modeling (ENM). These “carp” represent four stages of invasion of the continent (a long-established invader with a wide distribution, a long-established invader with a limited distribution, a spreading invader whose distribution is expanding, and a newly introduced potential invader that is not yet established), and as such illustrate the progressive reduction of distributional disequilibrium over the history of species' invasions.We used ENM to estimate the potential distributional area for each species in North America using models based on native range distribution data. Environmental data layers for native and introduced ranges were imported from state, national, and international climate and environmental databases. Models were evaluated using independent validation data on native and invaded areas. We calculated omission error for the independent validation data for each species: all native range tests were highly successful (all omission values <7%); invaded-range predictions were predictive for common and grass carp (omission values 8.8 and 19.8%, respectively). Model omission was high for introduced tench populations (54.7%), but the model correctly identified some areas where the species has been successful; distributional predictions for black carp show that large portions of eastern North America are at risk.ENMs predicted potential ranges of carp species accurately even in regions where the species have not been present until recently. ENM can forecast species' potential geographic ranges with reasonable precision and within the short screening time required by proposed U.S. invasive species legislation

Niche models in native ranges and in the United States.

<p>Ecological niche models for common carp (A, B), tench (C, D), grass carp (E, F), and black carp (G, H) on native and U.S. landscapes. Shading indicates the predicted suitability predicted (brick red = 7–10 models, canary red = 4–6 models, pink = 1–3 models). Occurrence points for each species are shown as training data (yellow circles) in the species' native range (A, C, E, G) or independent validation data (green triangles) in the native or introduced ranges (B, D, F, H).</p

Environmental data layers used in the development of the models presented herein.

<p>IPCC: Intergovernmental Panel on Climate Change, Climate Data Archive <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0005451#pone.0005451-IPCC1" target="_blank">[101]</a>. UM: University of Maryland <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0005451#pone.0005451-Hansen1" target="_blank">[102]</a>. USGS: United States Geological Survey, HYDRO1k Elevation Derivative Database <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0005451#pone.0005451-11" target="_blank">[103]</a>.</p