Miracle-dz/UniFAR-FTUs huggingface dataset:
Host specificity driving genetic structure and diversity in ectoparasite populations: Coevolutionary patterns in Apodemus mice and their lice

Abstract A degree of host specificity, manifested by the processes of host–parasite cospeciations and host switches, is assumed to be a major determinant of parasites’ evolution. To understand these patterns and formulate appropriate ecological hypotheses, we need better insight into the coevolutionary processes at the intraspecific level, including the maintenance of genetic diversity and population structure of parasites and their hosts. Here, we address these questions by analyzing large‐scale molecular data on the louse Polyplax serrata and its hosts, mice of the genus Apodemus, across a broad range of European localities. Using mitochondrial DNA sequences and microsatellite data, we demonstrate the general genetic correspondence of the Apodemus/Polyplax system to the scenario of the postglacial recolonization of Europe, but we also show several striking discrepancies. Among the most interesting are the evolution of different degrees of host specificity in closely related louse lineages in sympatry, or decoupled population structures of the host and parasites in central Europe. We also find strong support for the prediction that parasites with narrower host specificity possess a lower level of genetic diversity and a deeper pattern of interpopulation structure as a result of limited dispersal and smaller effective population size.
Eutrophication triggers contrasting multilevel feedbacks on litter accumulation and decomposition in fens.

Eutrophication is a major threat for the persistence of nutrient-poor fens, as multilevel feedbacks on decomposition rates could trigger carbon loss and increase nutrient cycling. Here, we experimentally investigate the effects of macronutrient (NPK) enrichment on litter quality of six species of sedge (Carex sp.), which we relate to litter decomposition rates in a nutrient-poor and nutrient-rich environment. Our research focused on four levels: we examined how eutrophication alters (1) fresh litter production ("productivity shift"), (2) litter stoichiometry within the same species ("intraspecific shift"), (3) overall litter stoichiometry of the vegetation under the prediction that low-competitive species are outcompeted by fast-growing competitors ("interspecific shift"), and (4) litter decomposition rates due to an altered external environment (e.g., shifts in microbial activity; "exogenous shift"). Eutrophication triggered a strong increase in fresh litter production. Moreover, individuals of the same species produced litter with lower C:N and C:P ratios, higher K contents, and lower lignin, Ca and Mg contents (intraspecific shift), which increased litter decomposability. In addition, species typical for eutrophic conditions produced more easily degradable litter than did species typical for nutrient-poor conditions (interspecific shift). However, the effects of nutrient loading of the external environment (exogenous shift) were contradictory. Here, interactions between litter type and ambient nutrient level indicate that the (exogenous) effects of eutrophication on litter decomposition rates are strongly dependent of litter quality. Moreover, parameters of litter quality only correlated with decomposition rates for litter incubated in nutrient-poor environments, but not in eutrophic environments. This suggests that rates of litter decomposition can be uncoupled from litter stoichiometry under eutrophic conditions. In conclusion, our results show that eutrophication affects litter accumulation and -decomposition at multiple levels, in which stimulatory and inhibitory effects interact. The cumulative effect of these interactions ultimately determine whether peatlands remain sinks or become sources of carbon under eutrophic conditions.
Surgical Management of Patellar Tendinopathy

Patellar tendinopathy, giving the clinical syndrome of “jumper's knee,” commonly presents in athletes whose activity involves eccentric loading of the knee, such as high jumpers and long jumpers. The pathology is degenerative rather than inflammatory, possibly as a result of repetitive microtrauma. The mainstay of management is nonoperative, with physical therapy and rehabilitation. If symptoms have not resolved after 6 months of conservative management, then surgery may be indicated. Many surgical procedures have been described, and results are generally good in properly selected patients. The authors' preferred technique is described here. Patellar tendinopathy results in a clinical syndrome of anterior knee pain with tenderness of the patellar tendon, most commonly at its insertion to the patella. Athletes whose sports involve repetitive, eccentric loading of the knee may develop anterior knee pain associated with tenderness at the inferior pole of the patella, the clinical syndrome commonly called “jumper's knee. ” Ultrasound and magnetic resonance imaging may reveal abnormal signal at the junction of the patella and the patellar tendon. Jumper's knee represents the classic insertional patellar tendinopathy, but patellar tendinopathy can affect the main body of the tendon. The condition may need to be managed surgically after failure of conservative treatment.
SUBSTITUTION PROCESSES IN MOLECULAR EVOLUTION. II. EXCHANGEABLE MODELS FROM POPULATION GENETICS

Substitution processes are of two sorts: origination processes record the times at which nucleotide mutations that ultimately fix in the population first appear, and fixation processes record the times at which they actually fix. Substitution processes may be generated by combining models of population genetics—here the symmetrical‐neutral, overdominance, underdominance, TIM, and SAS‐CFF models—with the infinite‐sites, no‐recombination model of the gene. This paper is mainly concerned with a computer simulation study of these substitution processes. The rate of substitution is shown to be remarkably insensitive to the strength of selection for models with strong balancing selection caused by the genealogical drift of mutations through alleles held in the population by selection. The origination process is shown to be more regular than Poisson for the overdominance, TIM, and SAS‐CFF models but more clustered for the underdominance model. A class of point processes called Sawyer processes is introduced to help explain these observations as well as the observation that the times between successive originations are nearly uncorrelated. Fixation processes are shown to be more complex than origination processes, with regularly spaced bursts of multiple fixations. An approximation to the fixation process is described. One important conclusion is that protein evolution is not easily reconciled with any of these models without adding perturbations that recur on a time scale that is commensurate with that of molecular evolution.
Biology of Blood Vessels in Hypertension

Increased peripheral vascular resistance is the hemodynamic characteristic of essential hypertension and is associated with structural and functional changes in resistance vessels. The major structural alterations constitute reduced vessel lumen diameter with thickening of the vascular wall. Only a 10% narrowing of the vessel lumen and a slight thickening of the vessel wall, which includes the medial and intimal layers, are sufficient to significantly increase peripheral resistance. At the cellular level, there is a significant increase in cell mass and collagen and elastin deposition with vascular smooth muscle hypertrophy and hyperplasia. Direct hemodynamic forces, as well as circulating and local growth regulators, stimulate cell growth in hypertensive vessels. Functional alterations that increase peripheral resistance include enhanced vascular reactivity to vasoconstrictor agents or impaired relaxation and reflect changes in excitation-contraction coupling and/or electrical properties of cells. Excess systemic or local production of vasoconstrictors or growth factors, abnormal agonist-receptor interactions, increased cell membrane permeability, defective transmembrane ion transport, intracellular calcium overload, exaggerated responses of the phosphoinositide signaling system, and altered endothelial function result in increased vascular smooth muscle growth and contractility. Whether these changes are a primary cause or secondary consequence of hypertension remains unclear but is a major focus of investigation.
Patterns of brain asymmetry in the perception of positive and negative facial expressions

The divided visual field technique was used to investigate the pattern of brain asymmetry in the perception of positive/approach and negative/withdrawal facial expressions. A total of 80 undergraduate students (65 female, 15 male) were distributed in five experimental groups in order to investigate separately the perception of expressions of happiness, surprise, fear, sadness, and the neutral face. In each trial a target and a distractor expression were presented simultaneously in a computer screen for 150 ms and participants had to determine the side (left or right) on which the target expression was presented. Results indicated that expressions of happiness and fear were identified faster when presented in the left visual field, suggesting an advantage of the right hemisphere in the perception of these expressions. Fewer judgement errors and faster reaction times were also observed for the matching condition in which emotional faces were presented in the left visual field and neutral faces in the right visual field. Other results indicated that positive expressions (happiness and surprise) were perceived faster and more accurately than negative ones (sadness and fear). Main results tend to support the right hemisphere hypothesis, which predicts a better performance of the right hemisphere to perceive emotions, as opposed to the approach–withdrawal hypothesis.
EFFECTS OF INTRINSIC AND EXTRINSIC FACTORS ON POPULATION FRAGMENTATION IN THREE SPECIES OF NORTH AMERICAN MINNOWS (TELEOSTEI: CYPRINIDAE)

Geographic patterns of genetic variation (mitochondrial DNA [mtDNA] and allozymes) were used to examine effects of intrinsic characteristics (e.g., vagility, habitat specificity, and reproductive behaviors) and extrinsic factors (e.g., climatic and geological history) on population fragmentation. The three species of cyprinid fishes examined (Tiaroga cobitis, Meda fulgida, and Agosia chrysogaster) occupied similar historical ranges within the lower Colorado River drainage, but differ in intrinsic characteristics conducive to population fragmentation. Relationships among populations were similar across species, reflecting common historical influences, but results indicate the distribution of variation among species is strongly affected by intrinsic characteristics. Variation within two species (T. cobitis and M. fulgida) is subdivided among populations, suggesting little gene flow among rivers. In contrast, similarity of A. chrysogaster populations throughout the Gila River drainage supports the hypothesis that levels of gene flow are high for this species. Levels of mtDNA divergence were much higher than expected for both T. cobitis and A. chrysogaster suggesting long‐term isolation of geographic regions. These results indicate that both long‐term and short‐term extrinsic factors have shaped basic patterns of variation within these fishes; however, the intrinsic characteristics of each species have strongly affected the population genetic structure of these fishes.
THE EFFECTS OF CONTRASTING MODES OF FERTILIZATION ON LEVELS OF INBREEDING IN THE MARINE INVERTEBRATE GENUS CORELLA

A simple difference in the body design of two species of marine urochordates in the ascidian genus Corella suggested that these species may differ in their mating systems. The two coexisting species share common life‐history traits and morphology with the exception of a difference in body design that affects site of fertilization and embryonic development. Corella inflata has internal fertilization and embryonic development, while C. willmeriana has external fertilization and embryonic development. The natural mating system of these two species of solitary ascidians was inferred by comparing the relative survival of selfed and outcrossed fertilizations in the laboratory. Corella inflata, the internal fertilizer, showed no difference in survival between selfed and outcrossed fertilizations at any developmental stage through metamorphosis and early juvenile development. In contrast, self‐fertilized crosses of C. willmeriana had significantly lower survival than outcrossed fertilizations even at the earliest scorable developmental stages. These results suggest that C. inflata may inbreed frequently in nature, while viable C. willmeriana offspring are primarily a result of outcrossing. The internally‐fertilizing species, C. inflata, showed approximately 10% male sterility in laboratory crosses despite apparent morphological hermaphroditism. The externally‐fertilizing, commonly outcrossing species, C. willmeriana, showed no difference in fertility between genders.
Digit ratio (2D:4D), salivary testosterone, and handedness

The length of the index finger relative to that of the ring finger, the 2D:4D ratio, has been taken to be a marker of the amount of testosterone (T) that was present in the foetal environment (Manning, Scutt, Wilson, & Lewis-Jones, 1998). It has also been suggested (Geschwind & Galaburda, 1987) that elevated levels of foetal T are associated with left-handedness and that adult levels of circulating T might relate to foetal levels (Jamison, Meier, & Campbell, 1993). We used multiple regression analyses to investigate whether there is any relationship between either left or right hand 2D:4D ratio and handedness. We also examined whether adult levels of salivary T (or cortisol, used as a control hormone) predict digit ratio and/or handedness. Although the 2D:4D ratio of neither the left nor the right hand was related to handedness, the difference between the digit ratios of the right and left hands, DR–L, was a significant predictor of handedness and of the performance difference between the hands on a peg-moving task, supporting previous findings (Manning & Peters, 2009; Manning et al., 1998; Manning, Trivers, Thornhill, & Singh, 2000; Stoyanov, Marinov, & Pashalieva, 2009). Adult circulating T levels did not predict the digit ratio of the left or right hand; nor was there a significant relationship between concentrations of salivary T (or cortisol) and either hand preference or asymmetry in manual skill. We suggest that the association between DR–L and hand preference arises because DR–L is a correlate of sensitivity to T in the developing foetus.
ECOLOGICAL AND GENETIC CONSEQUENCES OF POLLINATION BY SEXUAL DECEPTION IN THE ORCHID CALADENIA TENTACTULATA

Only orchids affect pollination by the deceptive sexual attraction of male insects, a syndrome particularly well developed in Australia. We examined the ecological and genetic consequences of exclusive pollination by sexually attracted male thynnine wasps in the orchid Caladenia tentaculata. Male wasps respond rapidly to flowers artificially presented in 1 × 1 m2 experimental patches. Sixty of 287 wasps approached within centimeters of the flower, but did not land. Of the remaining 79% who made floral contact, only 7.5% attempted copulation, the step critical for pollination. Wasps only rarely moved among patches (19% of flights) and none attempted copulation a second time, resembling observations in natural populations. We confirmed outcrossing and long distance pollen flow by monitoring how colored pollen moved in natural populations. Pollen movements approximated a linear rather than a leptokurtic distribution (mean distance: 17 m; maximum: 58 m). Pollinator visits varied independently of flower density in three of four populations with most solitary flowers being visited. Allozyme analysis revealed within‐population fixation indices (F) close to zero and low levels of differentiation (FST) among populations. Despite behavioral evidence for long distance pollen flow, significant local genetic structure exists, perhaps reflecting restricted seed dispersal. Long distance pollen flow in C. tentaculata may therefore promote outbreeding by minimizing pollen transfers among related neighbors. Although this species is self‐compatible, outcrossed progeny develop significantly faster than selfed progeny. Effective pollination at low flower densities could accentuate this advantage. The data are consistent with the predictions that deceptive pollination will result in long distance pollen flow, which may be of selective advantage at low density. Comparative studies of how food reward, food deceptive, and sexual deceptive pollination systems vary within a phylogenetic framework could further illuminate the evolution of sexual deception.
Under what conditions will right-handers use their left hand? The effects of object orientation, object location, arm position, and task complexity in preferential reaching

When reaching to objects, it is known that the preferred hand is selected significantly more often for midline and ipsilateral reaches, although right-handers are more likely to continue to use their right hand to reach for an object in contralateral space (Mamolo, Roy, Rohr, & Bryden, 2006). The current study examined the influence of object orientation, object location, task complexity, and initial position of the hands on a reaching task in a sample of 45 right-handed adults. Participants reached to and picked up a mug oriented in one of three ways (handle to right, left, or neutral position) located in one of three spatial positions (left, right, and midline) from each of two starting hand positions: right hand over left, and vice versa. Along with the expected results, an interesting pattern emerged where both the orientation of the object and the position of the hands had significant effects on hand selection, such that the use of the non-preferred left hand was augmented in conditions where preferred-hand use was awkward and biomechanically inefficient. The results will be discussed in light of current theories accounting for hand selection preferences.
A model treatment program for the head–injured substance abuser: Preliminary findings

This article describes a treatment program designed to provide holistic rehabilitation services to persons with traumatic brain injury who are diagnosed as chemically abusive or dependent. Unique aspects of the cognitive and behavioral sequelae of brain injury mandate a nontraditional approach to effective treatment of substance abuse. Program structure and components, staff development, service delivery, and reimbursement system are described. Case examples and group data are presented for the small sample of patients treated to date, with discussion of the difficulties, requirements, and needs for effective treatment programs for this population. The Importance of third-party reimbursement and support for the program cannot be overstated for such programs to be successful.
Breastfeeding predicts handedness

This study examined whether being breastfed predicts handedness. Two large representative samples from Britain (n=13,421) and Ireland (n=8,426) were used. Multivariate probit models are estimated, reporting the marginal effects of covariates on the probability of a child being right-handed. For both datasets, children who have been breastfed for a minimum period (between 1 month and 6 weeks) are significantly less likely to be left-handed. The results are robust to a variety of controls. Hence breastfeeding is an environmental factor that predicts handedness in a non-linear way, although the mechanism is unknown.
COMPLEX TRADE‐OFFS AND THE EVOLUTION OF STARVATION RESISTANCE IN DROSOPHILA MELANOGASTER

The measurement of trade‐offs may be complicated when selection exploits multiple avenues of adaptation or multiple life‐cycle stages. We surveyed 10 populations of Drosophila melanogaster selected for increased resistance to starvation for 60 generations, their paired controls, and their mutual ancestors (a total of 30 outbred populations) for evidence of physiological and life‐history trade‐offs that span life‐cycle stages. The directly selected lines showed an impressive response to starvation selection, with mature adult females resisting starvation death 4–6 times longer than unselected controls or ancestors—up to a maximum of almost 20 days. Starvation‐selected flies are already 80% more resistant to starvation death than their controls immediately upon eclosion, suggesting that a significant portion of their selection response was owing to preadult growth and acquisition of metabolites relevant to the stress. These same lines exhibited significantly longer development and lower viability in the larval and pupal stages. Weight and lipid measurements on one of the starvation‐selected treatments (SB1–5), its control populations (CB1–5), and their ancestor populations (B1–5) revealed three important findings. First, starvation resistance and lipid content were linearly correlated; second, larval lipid acquisition played a major role in the evolution of adult starvation resistance; finally, increased larval growth rate and lipid acquisition had a fitness cost exacted in reduced viability and slower development. This study implicates multiple life‐cycle stages in the response to selection for the stress resistance of only one stage. Our starvation‐selected populations illustrate a case that may be common in nature. Patterns of genetic correlation may prove misleading unless multiple pleiotropic interconnections are resolved.
THE EVOLUTION OF GENETIC CORRELATIONS: AN ANALYSIS OF PATTERNS

The genetic correlation is a central parameter of quantitative genetics, providing a measure of the rate at which traits respond to indirect selection (i.e., selection that does not act upon the traits under study, but some other trait with which they have genes in common). In this paper, I review the pattern of variation among four combinations of traits: life history × life history (L × L), morphological × morphological (M × M), life history × morphological (L × M), and behavioral × behavioral (B × B). A few other combinations were investigated, but insufficient data were obtained for separate analysis. A total of 1798 correlations, distributed over 51 different animal and plant species, were analyzed. The analysis was conducted at two levels: first by dividing the data set solely by trait combination, and second by blocking the data by trait combination and species. Because selection will tend to fix alleles that show positive correlations with fitness traits faster than those that are negative and because the latter are expected to arise more frequently by mutation, correlations between life‐history traits are predicted to be more often negative than those between morphological traits. This prediction was supported, with the ranking in decreasing proportion of negative correlations being: L × L > L × M > B × B > M × M. The mean magnitude of the genetic correlation shows little variation among morphological and life‐history combinations, and the distribution of values is remarkably flat. However, the estimated standard errors and the coefficient of variation (SE/rG) are large, making it difficult to separate biological factors influencing the pattern of dispersion from experimental error. Analysis of the phenotypic and genetic correlations suggest that for the combinations M × M and L × M, but not L × L or B × B, the phenotypic correlation is an adequate estimate of the genetic correlation.