Phenotypic plasticity of nest-mate recognition cues in formica exsecta ants

It is well established that many ant species have evolved qualitatively distinct species-specific chemical profile that are stable overlarge geographical distances. Within these species profiles quantitative variations in the chemical profile allows distinct colony-specific odours to arise (chemotypes) that are shared by all colony members. This help maintains social cohesion, includingdefence of their colonies against all intruders, including con-specifics. How these colony -level chemotypes are maintainedamong nest-mates has long been debated. The two main theories are; each ant is able to biochemically adjust its chemical profileto‘match’that of its nest-mates and or the queen, or all nest-mates share their individually generated chemical profile viatrophollaxis resulting in an average nest-mate profile. This‘mixing’idea is better known as theGestaltmodel. Unfortunately,it has been very difficult to experimentally test these two ideas in a single experimental design. However, it is now possible usingthe antFormica exsectabecause the compounds used in nest-mate recognition compounds are known. We demonstrate thatworkers adjust their profile to‘match’the dominant chemical profile within that colony, hence maintaining the colony-specificchemotype and indicates that a‘gestalt’mechanism, i.e. profile mixing, plays no or only a minor role

It takes two: Evidence for reduced sexual conflict over parental care in a biparental canid

In biparental systems, sexual conflict over parental investment predicts that the parent providing care experiences greater reproductive costs. This inequality in parental contribution is reduced when offspring survival is dependent on biparental care. However, this idea has received little empirical attention. Here, we determined whether mothers and fathers differed in their contribution to care in a captive population of coyotes (Canis latrans). We performed parental care assays on 8 (n = 8 males, 8 females) mated pairs repeatedly over a 10-week period (i.e., 5–15 weeks of litter age) when pairs were first-time breeders (2011), and again as experienced breeders (2013). We quantified consistent individual variation (i.e., repeatability) in 8 care behaviors and examined within- and among-individual correlations to determine if behavioral plasticity within or parental personality across seasons varied by sex. Finally, we extracted hormone metabolites (i.e., cortisol and testosterone) from fecal samples collected during gestation to describe potential links between hormonal mechanisms and individual consistency in parental behaviors. Parents differed in which behaviors were repeatable: mothers demonstrated consistency in provisioning and pup-directed aggression, whereas fathers were consistent in pup checks. However, positive within-individual correlations for identical behaviors (e.g., maternal versus paternal play) suggested that the rate of change in all behaviors except provisioning was highly correlated between the sexes. Moreover, positive among-individual correlations among 50% of identical behaviors suggested that personality differences across parents were highly correlated. Lastly, negative among-individual correlations among pup-directed aggression, provisioning, and gestational testosterone in both sexes demonstrated potential links between preparental hormones and labile parental traits. We provide novel evidence that paternal contribution in a biparental species reaches near equivalent rates of their partners

Identification of two novel powdery mildew resistance loci, Ren6 and Ren7, from the wild Chinese grape species Vitis piasezkii

Descriptive statistics of the phenotypic scores within the base mapping population 11-373. Powdery mildew symptoms in the field were evaluated in two subsequent years. Greenhouse, in vitro experiments and the qPCR-based molecular assay were carried out with three to four biological replicates of each seedling plant in 2014. (DOCX 14ย�kb

Distribution and Abundance of Glucocorticoid and Mineralocorticoid Receptors throughout the Brain of the Great Tit (Parus major)

The glucocorticoid stress response, regulated by the hypothalamic-pituitary-adrenal (HPA) axis, enables individuals to cope with stressors through transcriptional effects in cells expressing the appropriate receptors. The two receptors that bind glucocorticoids-the mineralocorticoid receptor (MR) and glucocorticoid receptor (GR)-are present in a variety of vertebrate tissues, but their expression in the brain is especially important. Neural receptor patterns have the potential to integrate multiple behavioral and physiological traits simultaneously, including self-regulation of glucocorticoid secretion through negative feedback processes. In the present work, we quantified the expression of GR and MR mRNA throughout the brain of a female great tit (Parus major), creating a distribution map encompassing 48 regions. This map, the first of its kind for P. major, demonstrated a widespread but not ubiquitous distribution of both receptor types. In the paraventricular nucleus of the hypothalamus (PVN) and the hippocampus (HP)-the two brain regions that we sampled from a total of 25 birds, we found high GR mRNA expression in the former and, unexpectedly, low MR mRNA in the latter. We examined the covariation of MR and GR levels in these two regions and found a strong, positive relationship between MR in the PVN and MR in the HP and a similar trend for GR across these two regions. This correlation supports the idea that hormone pleiotropy may constrain an individual's behavioral and physiological phenotype. In the female song system, we found moderate GR in hyperstriatum ventrale, pars caudalis (HVC), and moderate MR in robust nucleus of the arcopallium (RA). Understanding intra- and interspecific patterns of glucocorticoid receptor expression can inform us about the behavioral processes (e.g. song learning) that may be sensitive to stress and stimulate future hypotheses concerning the relationships between receptor expression, circulating hormone concentrations and performance traits under selection, including behavior

Experimental modulation of external microbiome affects nestmate recognition in harvester ants (Pogonomyrmex barbatus)

Social insects use odors as cues for a variety of behavioral responses, including nestmate recognition. Past research on nestmate recognition indicates cuticular hydrocarbons are important nestmate discriminators for social insects, but other factors are likely to contribute to colony-specific odors. Here we experimentally tested whether external microbes contribute to nestmate recognition in red harvester ants (Pogonomyrmex barbatus). We changed the external microbiome of ants through topical application of either antibiotics or microbial cultures. We then observed behavior of nestmates when treated ants were returned to the nest. Ants whose external microbiome was augmented with microbial cultures were much more likely to be rejected than controls, but ants treated with antibiotics were not. This result is consistent with the possibility that external microbes are used for nestmate recognition