Convergent and divergent patterns of morphological differentiation provide more evidence for reproductive character displacement in a wood cricket Gryllus fultoni (Orthoptera: Gryllidae)

<p>Abstract</p> <p>Background</p> <p>In ecological character displacement, traits involved in reproductive isolation may not evolve in arbitrary directions when changes in these traits are by-products of adaptation to an ecological niche. In reproductive character displacement, however, selection acts directly on reproductive characters to enhance the degree of reproductive isolation between sympatric populations. Thus, the direction of change in reproductive characters may be arbitrary in relation to changes in other morphological characters. We characterized both tegminal characters and characters indicative of body size in sympatric and allopatric populations of <it>Gryllus fultoni</it>, a species displaying character displacement in its calling song characters in areas of sympatry with <it>G. vernalis </it>populations, to infer the nature and direction of selection acting on reproductive and morphological characters in sympatry.</p> <p>Results</p> <p>Except for mirror area, the number of teeth in a file, and ovipositor length of <it>G. fultoni</it>, all male and female morphological characters in <it>G. fultoni </it>and <it>G. vernalis </it>exhibited a uniform tendency to decrease in size with increasing latitude. There was no significant variation in female morphological characters between sympatric and allopatric <it>G. fultoni </it>populations. However, males of sympatric and allopatric <it>G. fultoni </it>populations significantly differed in head width, hind femur length, and mirror area even after controlling for clinal factors. Head width and hind femur length of <it>G. fultoni </it>were more similar to those of <it>G. vernalis </it>in sympatric populations than in allopatric populations, resulting in morphological convergence of <it>G. fultoni </it>and <it>G. vernalis </it>in sympatry. However, the mirror area of <it>G. fultoni </it>displayed the divergent pattern in relation to the sympatric <it>G. vernalis </it>populations.</p> <p>Conclusion</p> <p>Divergence-enhancing selection may be acting on mirror area as well as calling song characters, whereas local adaptation or clinal effects may explain variation in other morphological characters in sympatric populations of <it>G. fultoni</it>. This study also suggests that structures and behaviors that directly enhance reproductive isolation may evolve together, independently of other morphological traits.</p

Is female preference for large sexual ornaments due to a bias to escape predation risk?

<p>Abstract</p> <p>Background</p> <p>A female preference for intense sexual visual signals is widespread in animals. Although the preferences for a signal <it>per se </it>and for the intensity of the signal were often regarded to have the identical origin, no study has demonstrated if this is true. It was suggested that the female fiddler crabs prefer males with courtship structures because of direct benefit to escape predation. Here we tested if female preference for both components (i.e. presence and size) of the courtship structure in <it>Uca lactea </it>is from the sensory bias to escape predation. If both components have the identical origin, females should show the same response to different-sized courtship structures regardless of predation risk.</p> <p>Results</p> <p>First, we observed responses of mate-searching female <it>U. lactea </it>to courting males with full-sized, half-sized and no semidomes which were experimentally manipulated. Females had a directional preference for males with bigger semidomes within normal variation. Thereafter, we tested the effect of predation risk on the female bias in the non-courtship context. When threatened by an avian mock predator, females preferentially approached burrows with full-sized semidomes regardless of reproductive cycles (i.e. reproductive periods and non-reproductive periods). When the predator cue was absent, however, females preferred burrows with semidomes without discriminating structure size during reproductive periods but did not show any bias during non-reproductive periods.</p> <p>Conclusions</p> <p>Results indicate that selection for the size of courtship structures in <it>U. lactea </it>may have an origin in the function to reduce predation risk, but that the preference for males with structures may have evolved by female choice, independent of predation pressure.</p

Genetic assessment of the subspecies status of Eurasian Magpies (Pica pica) in Norway

Based on phenotypes, two subspecies of Eurasian Magpies (Pica pica) are recognized in Norway, with nominate P. p. pica in southern Norway, and P. p. fennorum in northern Norway. In this study, we investigated whether there are genetically distinct groups of Magpies in Norway, which can be considered in the discussion of the subspecies status. We collected DNA from 61 Magpies from seven locations in Norway, and measured genetic diversity using two types of markers: mitochondrial DNA sequences and microsatellites. Genetic differentiation among the Magpies was extremely low. Most of the variance was within populations, and th e population identity and the putative subspecies border did not explain the genetic variance among the samples. Although microsatellite markers indicated genetic differentiation, the pattern was not consistent with the geographic locations of the sampling sites. Mismatch analysis suggested that the Magpie populations in Norway were formed by rapid expansion. Our results suggest that all the Magpies in Norway have originated from the same refugia after the last glaciation, their colonization in Norway happened quickly, and that the subspecies status of Magpies in Norway needs to be reconsidere

Genetic Traceability of Black Pig Meats Using Microsatellite Markers

Pork from Jeju black pig (population J) and Berkshire (population B) has a unique market share in Korea because of their high meat quality. Due to the high demand of this pork, traceability of the pork to its origin is becoming an important part of the consumer demand. To examine the feasibility of such a system, we aim to provide basic genetic information of the two black pig populations and assess the possibility of genetically distinguishing between the two breeds. Muscle samples were collected from slaughter houses in Jeju Island and Namwon, Chonbuk province, Korea, for populations J and B, respectively. In total 800 Jeju black pigs and 351 Berkshires were genotyped at thirteen microsatellite (MS) markers. Analyses on the genetic diversity of the two populations were carried out in the programs MS toolkit and FSTAT. The population structure of the two breeds was determined by a Bayesian clustering method implemented in structure and by a phylogenetic analysis in Phylip. Population J exhibited higher mean number of alleles, expected heterozygosity and observed heterozygosity value, and polymorphism information content, compared to population B. The FIS values of population J and population B were 0.03 and −0.005, respectively, indicating that little or no inbreeding has occurred. In addition, genetic structure analysis revealed the possibility of gene flow from population B to population J. The expected probability of identify value of the 13 MS markers was 9.87×10−14 in population J, 3.17×10−9 in population B, and 1.03×10−12 in the two populations. The results of this study are useful in distinguishing between the two black pig breeds and can be used as a foundation for further development of DNA markers

Rapid access to polycyclic N-heteroarenes from unactivated, simple azines via a base-promoted Minisci-type annulation

Conventional synthetic methods to yield polycyclic heteroarenes have largely relied on metal-mediated arylation reactions requiring pre-functionalised substrates. However, the functionalisation of unactivated azines has been restricted because of their intrinsic low reactivity. Herein, we report a transition-metal-free, radical relay pi-extension approach to produce N-doped polycyclic aromatic compounds directly from simple azines and cyclic iodonium salts. Mechanistic and electron paramagnetic resonance studies provide evidence for the in situ generation of organic electron donors, while chemical trapping and electrochemical experiments implicate an iodanyl radical intermediate serving as a formal biaryl radical equivalent. This intermediate, formed by one-electron reduction of the cyclic iodonium salt, acts as the key intermediate driving the Minisci-type arylation reaction. The synthetic utility of this radical-based annulative pi-extension method is highlighted by the preparation of an N-doped heptacyclic nanographene fragment through fourfold C-H arylation. The functionalisation of unactivated azines has been restricted because of their intrinsic low reactivity. Here the authors show a transition-metal-free, radical relay pi-extension approach to produce N-doped polycyclic aromatic compounds directly from simple azines and cyclic iodonium salts

Multiple Endocrine Neoplasia Type 1 with Multiple Leiomyomas Linked to a Novel Mutation in the MEN1 Gene

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominantly inherited syndrome. MEN1 is characterized by the presence of functioning and nonfunctioning tumors or hyperplasia of the pituitary gland, parathyroid glands, and pancreatic islet cells. In addition, MEN1 carriers can have adrenal or thyroid tumors and non-endocrine tumors, such as lipomas, angiofibromas, and leiomyomas. Although leiomyoma is not a major component of MEN1, it is thought to occur more frequently than expected. However, there has been no report of a case of MEN1 with leiomyoma in Korea so far. This report describes a patient with multiple leiomyomas in MEN1. A 50-year-old woman was referred for further evaluation of elevated calcium levels and osteoporosis. Biochemical abnormalities included hypercalcemia with elevated parathyroid hormone. There was hyperprolactinemia with pituitary microadenoma in sella MRI. An abdominal MRI demonstrated adrenal nodules and leiomyomas in the bladder and uterus. Endoscopic ultrasonography demonstrated esophageal leiomyoma and pancreatic islet cell tumor. A subtotal parathyroidectomy with thymectomy was performed. Sequencing of the MEN1 gene in this patient revealed a novel missense mutation (D350V, exon 7). This is the first case of MEN1 accompanied with multiple leiomyomas, parathyroid adenoma, pituitary adenoma, pancreatic tumor, and adrenal tumor

Adjustments to facilitate communication in noisy environments

Animals communicate with sounds, odors and smells to attract mates, defend territories or warn against predators. Communication signals thus provide vital functions for reproduction and survival, yet are often used in environments with high or fluctuating levels of noise. Natural conditions, such as a waterfall, heavy rains or winds can create high levels of acoustic, visual and vibratory noise, and have shaped animal communication systems during their evolutionary history. Nowadays, human activities also create stimuli such as the sound made by transportation vehicles, or light emitted at night by streetlamps that force animals to adapt their signaling behavior. In this article we review the various ways in which animals are affected by noise in their living environment and outline how they can cope with it. We distinguish between the effects of noise on the receiver, as well as the producer of communication signals in different perceptual systems, such as the acoustical, visual and chemical domain. We close-off by reviewing some evidence that noise, as well as the signals and cues it can affect, is not restricted to a single modality, but that animals often combine information across the senses. We finish by providing some interesting avenues for studies on multimodal communication and multisensory pollution in animal research