Geometric Entropy for Lead vs Top-Rope Rock Climbing

International Journal of Exercise Science 9(2): 168-174, 2016. The complexity of movement of a rock climber’s center of mass during an ascent has been described as geometric entropy (GE). It has been proposed that lower geometric entropy could represent more fluid and economical movement during climbing. The purpose of the present study was to measure GE during rock climbing ascents under a lead condition (LD), where the climber connects a safety rope to several intermediate anchors during the ascent and under a top-rope condition (TR), where the safety rope is always anchored above the climber. Six experienced rock climbers volunteered to participate in the study. Each participant ascended a route on natural rock outdoors under three conditions. The first ascent was performed in a top-rope condition as an accommodation trial. The two remaining ascents were performed as LD and top-rope (TR2) in random order. Each LD and TR2 ascent was recorded via digital video at 30 Hz. A single point at the back center of each climber’s waist harness was manually digitized from the video images at 6 Hz and interpreted as the climber’s center of mass (CM). The displacement of CM was expressed as the line of motion (LM). Geometric Entropy (GE) was calculated as GE = ln((2∙LM)/CH)), where CH was the value of the convex hull about the LM. A within subjects, repeated measures ANOVA with Bonferroni post hoc testing was utilized to test for differences among ascent conditions with significance set at P \u3c0.05. Mean (±s.d) values for LM and GE were 81.5±11.3 m vs 77.6±7.3 m and 1.021±0.133 vs 0.924±0.062 for LD and TR2 respectively. There were no significant differences for LM and GE between ascent conditions. It was concluded that LM and GE do not vary between LD and TR ascent conditions

Plasticity of boldness in rainbow trout, Oncorhynchus mykiss: do hunger and predation influence risk-taking behaviour?

Boldness, a measure of an individual's propensity for taking risks, is an important determinant of fitness but is not necessarily a fixed trait. Dependent upon an individual's state, and given certain contexts or challenges, individuals may be able to alter their inclination to be bold or shy in response. Furthermore, the degree to which individuals can modulate their behaviour has been linked with physiological responses to stress. Here we attempted to determine whether bold and shy rainbow trout, Oncorhynchus mykiss, can exhibit behavioural plasticity in response to changes in state (nutritional availability) and context (predation threat). Individual trout were initially assessed for boldness using a standard novel object paradigm; subsequently, each day for one week fish experienced either predictable, unpredictable, or no simulated predator threat in combination with a high (2% body weight) or low (0.15%) food ration, before being reassessed for boldness. Bold trout were generally more plastic, altering levels of neophobia and activity relevant to the challenge, whereas shy trout were more fixed and remained shy. Increased predation risk generally resulted in an increase in the expression of three candidate genes linked to boldness, appetite regulation and physiological stress responses – ependymin, corticotrophin releasing factor and GABAA – but did not produce a significant increase in plasma cortisol. The results suggest a divergence in the ability of bold and shy trout to alter their behavioural profiles in response to internal and exogenous factors, and have important implications for our understanding of the maintenance of different behavioural phenotypes in natural populations

Evolved high aerobic capacity has context-specific effects on gut microbiota

Publisher Copyright: Copyright © 2022 Hanhimäki, Watts, Koskela, Koteja, Mappes and Hämäläinen.Gut microbiota is expected to coevolve with the host's physiology and may play a role in adjusting the host's energy metabolism to suit the host's environment. To evaluate the effects of both evolved host metabolism and the environmental context in shaping the gut microbiota, we used a unique combination of (1) experimental evolution to create selection lines for a fast metabolism and (2) a laboratory-to-field translocation study. Mature bank voles Myodes glareolus from lines selected for high aerobic capacity (A lines) and from unselected control (C lines) were released into large (0.2 ha) outdoor enclosures for longitudinal monitoring. To examine whether the natural environment elicited a similar or more pronounced impact on the gut microbiota of the next generation, we also sampled the field-reared offspring. The gut microbiota were characterized using 16S rRNA amplicon sequencing of fecal samples. The artificial selection for fast metabolism had minimal impact on the gut microbiota in laboratory conditions but in field conditions, there were differences between the selection lines (A lines vs. C lines) in the diversity, community, and resilience of the gut microbiota. Notably, the selection lines differed in the less abundant bacteria throughout the experiment. The lab-to-field transition resulted in an increase in alpha diversity and an altered community composition in the gut microbiota, characterized by a significant increase in the relative abundance of Actinobacteria and a decrease of Patescibacteria. Also, the selection lines showed different temporal patterns in changes in microbiota composition, as the average gut microbiota alpha diversity of the C lines, but not A lines, was temporarily reduced during the initial transition to the field. In surviving young voles, the alpha diversity of gut microbiota was significantly higher in A-line than C-line voles. These results indicate that the association of host metabolism and gut microbiota is context-specific, likely mediated by behavioral or physiological modifications in response to the environment.Peer reviewe

HPI reactivity does not reflect changes in personality among trout introduced to bold or shy social groups

Physiological stress responses often correlate with personalities (e.g. boldness). However, this relationship can become decoupled, although the mechanisms underlying changes in this relationship are poorly understood. Here we quantify (1) how an individual’s boldness (response to novel objects) in rainbow trout, Oncorhynchus mykiss, changes in response to interactions with a population of either bold or shy conspecifics and we (2) measured associated post-stress cortisol levels. Initially-bold trout became shyer regardless of group composition, whereas shy trout remained shy demonstrating that bold individuals are more plastic. Stress-induced plasma cortisol reflected the original personality of fish but not the personality induced by the treatment, irrespective of population personality. Change in boldness of bold trout may indicate preference towards initially subordinate behaviour when joining a new population. However, here we provide further evidence that behavioural and physiological parameters of coping styles may become uncoupled whereby behavioural changes are not correlated with stress responsiveness

The complete mitochondrial genome of the broad-winged damselfly <i>Mnais costalis</i> Selys (Odonata: Calopterygidae) obtained by next-generation sequencing

<p>We used next-generation sequencing to characterise the complete mitochondrial genome of the damselfly <i>Mnais costalis</i> (Odonata, Calopterygidae). Illumina paired end reads were mapped against COI and 16S sequences from <i>M. costalis</i> and then extended using an iterative <i>de novo</i> map procedure. The final assembly was a contiguous sequence of 15,487 bp, which contained all standard mitochondrial coding regions and the putative A+T rich region. The gene configuration of the <i>M. costalis</i> mitogenome is similar to that of other odonates, comprising 13 protein-coding genes, large and small rRNA genes, and 22 tRNA genes. We found three intergenic spacers that are also present in all available whole odonate mitogenomes. Base composition of the <i>M. costalis</i> mitogenome is 40% (A), 20% (C), 14% (G) and 26% (T), with a high A+T content (66%). The characterisation of the complete mitochondrial genome of <i>M. costalis</i> adds to the growing list of mitogenomes currently available for odonates, and will help to improve primer design for future population genetic studies. A phylogenetic analysis including the currently available mitochondrial genome sequences of odonates suggests that <i>Epiophlebia superstes</i> is more closely related to the Zygoptera than to the Anisoptera.</p

Exposure to Environmental Radionuclides Associates With Tissue-Specific Impacts on Telomerase Expression and Telomere Length

Telomeres, the protective structures at the ends of chromosomes, can be shortened when individuals are exposed to stress. In some species, the enzyme telomerase is expressed in adult somatic tissues, and potentially protects or lengthens telomeres. Telomeres can be damaged by ionizing radiation and oxidative stress, although the effect of chronic exposure to elevated levels of radiation on telomere maintenance is unknown for natural populations. We quantified telomerase expression and telomere length (TL) in different tissues of the bank vole Myodes glareolus, collected from the Chernobyl Exclusion Zone, an environment heterogeneously contaminated with radionuclides, and from uncontaminated control sites elsewhere in Ukraine. Inhabiting the Chernobyl Exclusion Zone was associated with reduced TL in the liver and testis, and upregulation of telomerase in brain and liver. Thus upregulation of telomerase does not appear to associate with longer telomeres but may reflect protective functions other than telomere maintenance or an attempt to maintain shorter telomeres in a stressful environment. Tissue specific differences in the rate of telomere attrition and apparent radiosensitivity weaken the intra-individual correlation in telomere length among tissues in voles exposed to radionuclides. Our data show that ionizing radiation alters telomere homeostasis in wild animal populations in tissue specific ways

First record of the invasive pest Drosophila suzukii in Ukraine indicates multiple sources of invasion

Drosophila suzukii, commonly known as the spotted-wing Drosophila, is an invasive polyphagous fruit pest, which has emerged as a global threat to agriculture in the Americas and in Europe. Due to the rapid spread, great economic losses and its pest behavior, D. suzukii represents a powerful model for invasion biology and pest management studies. However, its current European distribution, invasion routes and levels of genetic diversity in populations of D. suzukii are poorly understood. We present the first report of D. suzukii from Ukraine, with the invasion likely occurring close to 2014. The pattern of genetic variation at cytochrome oxidase I among D. suzukii populations from Europe, USA and Asia reveals comparatively high genetic diversity in the Ukrainian population of this pest species, suggesting a complex invasion scenario from multiple sources. Further monitoring patterns of genetic variation across space and time, to better understand the invasion routes of this invasive insect pest, will be an essential part for developing successful pest management strategies