The compound ascidian Botryllus schlosseri reproduces asexually, and forms colonies to adhere to matrices such as rocks. This species has developed a mechanism to distinguish between self stem cells and invasive parasitizing nonself cells from other individuals of the same species, probably as a defense against parasitism. It is highly likely that such adult colony histocompatibility is controlled differently from its gametic allorecognition during fertilization. Allorecognition in adults is controlled by a single fusion/histocompatibility (FuHC) locus. In 2005, a candidate gene responsible for the phenotype associated with this genetic locus, named cFuHC, was reported; however, this proposal was subsequently refuted, and the actual determinant may exist elsewhere within the FuHC locus. Given that its is unlikely that a single gene could produce the diversity of FuHC alleles needed to determine individual identity and to distinguish self from nonself colonies, it is possible that the FuHC locus consists of a cluster of multiple determinants aligned in tandem.

The repertoires of most songbirds consist of two or more different song types. Studies on a growing number of species have indicated that song types are used selectively in different contexts. For example, two bush warblers (Cettia diphone and C. cettia) use song types selectively in spontaneous singing and playback-evoked singing. Most male brownish-flanked bush warblers (C. fortipes) have two distinct song types. In this study, we tested whether these two song types are used selectively in different contexts. Most frequency and temporal variables are significantly different between these two song types, but neither song type is used more frequently during or after playback compared to spontaneous singing. Additionally, males did not respond differently to the two song types during playback experiments. In conclusion, these two song types differ significantly in both frequency and temporal variables, but we did not find any evidence that they are used selectively in different contexts. Comparing two related bush warblers (C. diphone and C. cettia) that selectively use different song types in different contexts, our study offers further evidence that avian vocalization is a plastic characteristic and can vary considerably, even among closely related species.

Most of amphibians belonging to family Rhacophoridae live in arboreal habitats. A large number of antimicrobial peptides (AMPs) have been identified from amphibian skins. No antimicrobial peptide from Rhacophoridae amphibians has been reported. In this study, we purified and characterized a novel antimicrobial peptide, pleurain-a1-thel from skin secretions of the tree frog, Theloderma kwangsiensis. Its amino acid sequence was determined as RILTMTKRVKMPQLYKQIVCRLFKTC by Edman degradation, mass spectrometry analysis and cDNA cloning. There are two cysteines, which form an intra-molecular disulfide bridge, in the sequence of pleurain-a1-thel. Pleurain-a1-thel exerted potential antimicrobial activities against wide spectrum of microorganisms, including Gram-negative and -positive bacteria and fungi. It exerted little hemolytic activity in human or rabbit red cells. To the best of our knowledge, this is the first report of antimicrobial peptide from Rhacophoridae amphibians.

Earthworms ingest various materials in addition to food items, such as soil particles. Most earthworms of the family Megascolecidae, a dominant family in Japan, have intestinal caeca connected directly to the intestinal tract. The function of the caeca has not been demonstrated, although it is thought to be associated with digestion. We investigated the activity of the digestive enzymes amylase, phosphatase, cellulase, and protease in different regions of the gut, including the intestinal caeca, in three species of megascolecid earthworms, Pheretima heteropoda, Pheretima hilgendorfi, and Pheretima sieboldi. Activities of several enzymes were high in the intestinal caeca; in particular, protease activity was higher in the caeca than that in the anterior gut, foregut, midgut, and hindgut in all three species. Moreover, the ratio of enzyme activities in the intestinal caeca to whole-gut tended to be higher in manicate intestinal caeca than in simple intestinal caeca. These results suggest that the digestive system of earthworms relies on the intestinal caeca.

Ca²⁺ plays important roles in animal development and behavior. Various Ca²⁺ transients during development have been reported in non-neuronal tissues, mainly by using synthesized calcium indicators. Here we used GCaMP3, a genetically encoded calcium indicator, to monitor stochastic Ca²⁺ waves, in zebrafish embryos. To express GCaMP3 systemically throughout the body, its mRNA was injected into fertilized eggs. In the neuroepithelium of developing anterior brain and retina at 12–20 hours post-fertilization, we found spontaneously occurring stochastic Ca²⁺ waves. Each Ca²⁺ wave typically appeared in a randomly distributed spot, spread for 5–60 sec to form an area whose position and size varied each time with a diameter ranging from 10 to 160 µm, and then shrank and decreased to 50% brightness in 4–67 sec. A precise examination of the cellular distribution using Nipkow disk multibeam confocal laser scanning indicated that the Ca²⁺ waves spread cell by cell. 2-APB, IP₃-receptor inhibitor, but not carbenoxolone, a gap junction blocker, inhibit these Ca²⁺ waves. Stronger fluorescence was found in the cytoplasm compared to the nuclei in the resting cells, and localized fluorescence was observed at the spindle poles in dividing cells. Ca²⁺ waves also spread through the dividing cells. Our results reveal a novel type of cell-to-cell communication through the neuroepithelium in the developing zebrafish brain and retina, distinct from communication through neuron-neuron circuits. Our findings also indicated that GCaMP3 was useful for monitoring both stochastic and behavior-related Ca²⁺ waves in the nervous system and skeletal muscles in zebrafish embryos.

Fruits are highly important food resources for mammals in Mediterranean Europe, and due to the dominance of oaks (Quercus sp.), acorns are among those used by a vast array of species, including rodents. The metabolic yield of acorn intake may determine a selection pattern: preference for fat, carbohydrate, and consequently energy-rich fruits; or avoidance of fruits containing high concentrations of secondary chemical compounds (e.g., tannic acid). We studied the acorn feeding selection pattern of wood mice (Apodemus sylvaticus) inhabiting a mixed oak woodland, southwest Portugal, using an experiment conducted in an open-air enclosure. We tested which variables associated with the wood mouse (e.g., sex) and acorns (e.g., size and nutrient content) from three oak species (holm Q. rotundifolia, Portuguese Q. faginea and cork Q. suber oak) could be constraining acorn consumption. Our results indicate that wood mice are selecting acorns of the most common oak species (Q. suber), probably due to their previous familiarization with the fruit due to its dominance in the ecosystem but probably also because its chemical characteristics (sugar contents). Rodent gender and acorn morphology (width) are also influential, with females more prone to consume acorns with smaller width, probably due to handling limitation. This selective behaviour may have consequences for dispersion and natural regeneration of the different oak species.

Liver X receptors, LXRs, are ligand-activated transcription factors that belong to the group H nuclear receptor (NR) superfamily. In this study, an LXR (HrLXR) cDNA was cloned from the ascidian Halocynthia roretzi hepatopancreas and characterized to examine the functional conservation of ancestral LXRs in chordates. A phylogenetic analysis of HrLXR showed that it belongs to the tunicate (urochordate) LXR subgroup, which is distinct from vertebrate LXRs. Quantitative real-time PCR analysis revealed that HrLXR mRNA was expressed predominantly in the gills, and highly expressed in unfertilized eggs followed by decrease at later embryonic and larval stages. Unexpectedly, HrLXR was not activated by GW3965, whereas a synthetic ligand for a farnesoid X receptor, GW4064, activated HrLXR. This activation was abolished by the deletion of 51 amino acids from the N-terminus. In a mammalian two-hybrid system, HrLXR interacted with HrRXR in the presence of GW4064 or 9-cis retinoic acid. The injection of GW3965 and GW4064 in vivo increased the ATPbinding cassette sub-family G member 4 and HrLXR mRNA levels in the hepatopancreas and gills. These results suggest that the mRNA expression and transcriptional properties of HrLXR are different from those of vertebrate LXRs, although HrLXR is likely responsive to the related NR ligand, GW4064.

Sex Identification of monomorphic birds, especially endangered avian species, is essential for ecological study and biodiversity conservation. In this study, two popular primer sets of 2550F/2718R and P2/P8, which were designed to amplify different fragments of chromodomain-helicase-DNA binding protein 1 (CHD1) genes mapped on both Z and W chromosomes in birds, were used to identify for the first time the sex of individuals of the endangered species crested ibis (Nipponia nippon) in a large number of samples. An improved primer set of 2467F/2530R was re-designed to be specific to crested ibis following their conserved sequences derived from the 2550F/2718R primers. PCR products of the new primers were conveniently visualized with two bands of 552 base pairs (bp) and 358 bp for females, but a single band of 552 bp for males in routine 1.8% agarose gel. Similarly, the P2/P8 primer set amplified two fragments of 398 bp and 381 bp from females but one fragment of 398 bp from males; however, a high resolution involving 10% Polyacrylamide gel had to be employed to resolve the 17 bp insertions/deletions (in/dels) present between the two amplicons in females. In addition, a microsatellite locus NnNF05 was validated to be sex-linked and shown to be effective in the sexing of crested ibis, supporting its utility in non-invasive sampling. This study provides a rapid, convenient, and reliable molecular assay for improving sex identification in the monomorphic and monogamous crested ibis, and thus facilitates the selection of breeding pairs in captive programs and reintroduction initiatives.

This study presents the first light microscopy-based description of the cloacal anatomy of male Carpathian newts (Lissotriton montandoni). This European newt species hybridizes with its sister species, the smooth newt (L. vulgaris), despite a high level of prezygotic isolation. The goal of the study was to ascertain possible anatomical differences in cloacal anatomy, especially pheromone and spermatophore producing glands, which might potentially affect reproductive isolation between L. montandoni and L. vulgaris. The cloaca of L. montandoni males consists of the cloacal tube, cloacal chamber, pseudopenis, and aggregations of cloacal glands. Four main types of cloacal glands were recognized. Pheromone-producing dorsal glands are of two types due to differences in their secretory epithelium: cuboidal and high prismatic. The remaining glands: ventral, pelvic, and Kingsbury's glands, are most likely involved in the synthesis of spermatophore components. Two distinct groups of ventral glands were identified: posterior and anterior ventral glands. In comparison with L. vulgaris, no evident differences were found that could potentially affect courtship pheromone synthesis by dorsal glands or the base and the cap of the spermatophore produced by the remaining cloacal glands.

Sixty-three continuous osteological characters (18 skull continuous characters and the total length of neurocranium, 45 continuous characters of 15 elements of the viscerodermal skeleton) were analyzed and included in the reconstruction of phylogenetic relationships of the six Euro-Mediterranean mullet species from the South Adriatic Sea: Mugil cephalus Linnaeus, 1758; Liza saliens Risso, 1810; Liza aurata Risso, 1810; Liza ramada Risso, 1826; Chelon labrosus Risso, 1826 and Oedalechilus labeo Cuvier, 1829. The study reveals that Sphyraenidae was separated clearly from Mugilidae, C. labrosus and three Liza species form a common cluster (L. ramada and L. saliens being the closest), while O. labeo and M. cephalus cluster together.

Triops granarius (Lucas) is a freshwater crustacean that is distributed from South Africa to the Eurasian continent. This species lives in temporary water pools and is exposed to desiccation and extreme temperatures after the water dries up in its habitat. To withstand this severe environment, Triops eggs enter anhydrobiosis when dehydrated. To clarify the physiological characteristics of T. granarius anhydrobiosis, we examined hatching rates after rehydration of eggs that were dehydrated at several humidity levels for 10 or 100 days. Lower humidity produced higher hatching rates when dehydration was continued for 100 days. These results suggest that drying at low humidity is required for long-term anhydrobiosis of T. granarius eggs. The eggs survived desiccation when dehydrated at the blastula, gastrula, and early organogenesis stages. The most dehydration-tolerant stage was early organogenesis. Non-dehydrated eggs hatched after temperature treatments of up to 50°C for 1 h, but did not hatch after exposure to 60°C for 1 h in air and under water. Similar results were obtained for dehydrated eggs exposed to high temperatures under water. In contrast, dehydrated eggs hatched after 1 h at 80°C in air but did not after 1 h at 90°C in air. Our results show that Triops eggs exhibit tolerance for desiccation and high temperature in a dried state, once they have entered anhydrobiosis.

Two new species of Caecinae are described from the Brazilian coast. Specimens of Caecum metamorphosicum sp. nov. were collected from northern to southeastern Brazil. The teleoconch V of this species is characterized by strong, raised, quadrangular, rather closely arranged axial ribs, except the last two to three preceding the aperture, which are slightly larger and more widely separated, and a finger-shaped mucro. Specimens of Caecum trindadense sp. nov. were only collected from southeastern Brazil. The teleoconch VI of this species is characterized by conspicuous, sinuous longitudinal striae, finger-shaped mucro, and rather smooth varix. The protoconch and all growth stages of C. metamorphosicum sp. nov. and C. trindadense sp. nov. are described and figured here based on scanning electron microscopy. A brief discussion on the biodiversity of Caecidae on the Atlantic coast of South America is given. This report provides a basis for the better recognition of growth stages among members of Caecinae.