We analyzed the intraspecific gene genealogies of three Leptocarabus ground beetle species (L. seishinensis, L. semiopacus, L. koreanus) in South Korea using sequence data from the mitochondrial cytochrome oxidase subunit I (COI) and nuclear 28S rRNA (28S) genes, and compared phylogeographical patterns among the species. The COI data detected significant genetic differentiation among local populations of all three species, whereas the 28S data showed genetic differentiation only for L. seishinensis. The clearest differentiation of L. seishinensis among local populations was between the northern and southern regions in the COI clades, whereas the 28S clade, which likely indicates relatively ancient events, revealed a range expansion across the northern and southern regions. Leptocarabus semiopacus had the most shallow differentiation of the COI haplotypes, and some clades occurred across the northern and southern regions. In L. koreanus, four diverged COI clades occurred in different regions, with partial overlaps. We discuss the difference in phylogeographical patterns among these Leptocarabus species, as well as between these and other groups of carabid beetles in South Korea.

Recent investigations into the encrusting anemone genus Zoanthus using molecular and morphological techniques have begun to bring order to this taxonomically neglected group. Previous studies have confirmed the existence of three distinct species present in southern Japan: Z. sansibaricus, Z. kuroshio, and Z. gigantus. Results from such studies show species of Zoanthus to be highly morphologically plastic, often incorporating morphotypes with varying oral disk color and oral disk diameter. Literature lists the species Z. aff. vietnamensis as occurring in southern Japan and throughout the western Pacific Ocean, but due to the morphological plasticity of Zoanthus species, a re-examination of Z. aff. vietnamensis using molecular techniques was needed. Here, using mitochondrial 16S rDNA and the nuclear internal transcribed spacer of ribosomal DNA (ITS-rDNA) sequences, as well as morphological data, we have examined several nominal Z. aff. vietnamensis samples collected from Kagoshima Bay and Yakushima Island, Japan. Based on polyp length and diameter, oral disk diameter, mesentery and tentacle numbers, and colony form, Z. aff. vietnamensis is easily distinguishable from Z. sansibaricus, Z. kuroshio, and Z. gigantus. However, despite these clear morphological differences, our mitochondrial and nuclear sequence-based phylogenies indicate that Z. aff. vietnamensis and Z. kuroshio are very closely related (perhaps conspecific), highlighting the morphological plasticity of this genus and the difficulty of species identification based on morphological data alone.

We conducted a field study of the life cycle of the eusirid gammaridean amphipod Sternomoera rhyaca Kuribayashi, Mawatari, and Ishimaru, 1996 in a stream at Gokibiru, Hokkaido, Japan over the course of two non-consecutive years. This species is biennial; it spends most of its life in freshwater, but undertakes a short catadromous migration to the sea for reproduction. Reproduction occurs from March-June. Mature adults drift downstream to the sea singly and in precopulating pairs. Copulation and oviposition in the marsupium occur in mixed water at the stream mouth. Males die after copulation; ovigerous females return upstream by walking or swimming, where their eggs develop and hatch, after which the females also die. Juveniles remain in the stream, growing until they reach sexual maturity. Laboratory experiments showed that survivorship of all stages was lowest in seawater and highest in freshwater, though juveniles survived equally well in mixed water (50% seawater) and freshwater. Eggs developed to hatching only in freshwater; hatchlings in seawater and mixed water died within one and 21 days, respectively. Thus, S. rhyaca is well adapted to freshwater. Indeed, the only stages that required elevated salinity were copulation and subsequent oviposition, and we speculate that freshwater inhibits the female pre-reproductive molt. Because the life cycle of S. rhyaca has the most ontogenetically and temporally restricted saltwater phase known in any catadromous animal, its origin and maintenance are of evolutionary interest. We discuss two alternative hypotheses for the origin of the migratory life cycle, and discuss its maintenance in terms of fitness costs and benefits.

Fighting behavior in male crickets is already well described, and some of the mechanisms underlying aggression and aggressive motivation have already been revealed. Much less is known about female/female interactions. Here, we report that adult female crickets that had been isolated for several days readily entered into agonistic interactions with conspecific individuals. Characteristic dyadic encounters between isolated females escalated in a stepwise manner and were concluded with the establishment of a dominant/subordinate relationship. For 15 to 30 minutes following an initial fight, former subordinate females showed a dramatic change in agonistic behavior. If they were paired with the former dominant opponent during this interval, a significant majority did not enter into any aggressive interaction but instead actively avoided the opponent. A similar experience-based and time-dependent increase in avoidance was observed when former subordinate females were paired with unfamiliar naïve opponents. However, when faced with an unfamiliar subordinate individual in the second encounter, no such increase in avoidance behavior was observed. We propose that the observed changes in the behavior of former subordinate females are the consequence of a change in the general state of arousal and of the recognition of dominance status, but not of individual recognition. The fact that former dominant individuals did not show similar experience-based changes in agonistic behavior suggests that dominant/subordinate relationships between pairs of female crickets are maintained mainly by the behavior of subordinate individuals.

The mouse Polycomb group (PcG) protein M33 forms nuclear complexes with the products of other PcG members and maintains repressed states of developmentally important genes, including homeotic genes. In this context, nuclear localization is a prerequisite for M33 to exert its function. However, we previously found that M33 in mouse liver shuttles dynamically between the nucleus and the cytoplasm, depending on the proliferative states of cells, coupled with phosphorylation and dephosphorylation of M33 protein. To understand the mechanism and significance of this phenomenon, we identified the functional nuclear localization signal (NLS) of M33 protein. Deletion mutants that lack a particular one of three putative NLS motifs failed to localize in the nucleus. Green fluorescent protein (GFP) fused to this motif specifically localized in the nucleus. We conclude that this amino-acid stretch in M33 acts as the functional NLS for this protein.

Microscopic observation of the skin of Plestiodon lizards, which have body stripes and blue tail coloration, identified epidermal melanophores and three types of dermal chromatophores: xanthophores, iridophores, and melanophores. There was a vertical combination of these pigment cells, with xanthophores in the uppermost layer, iridophores in the intermediate layer, and melanophores in the basal layer, which varied according to the skin coloration. Skin with yellowish-white or brown coloration had an identical vertical order of xanthophores, iridophores, and melanophores, but yellowish-white skin had a thicker layer of iridophores and a thinner layer of melanophores than did brown skin. The thickness of the iridophore layer was proportional to the number of reflecting platelets within each iridophore. Skin showing green coloration also had three layers of dermal chromatophores, but the vertical order of xanthophores and iridophores was frequently reversed. Skin showing blue color had iridophores above the melanophores. In addition, the thickness of reflecting platelets in the blue tail was less than in yellowish-white or brown areas of the body. Skin with black coloration had only melanophores.

Reptilian scales are mainly composed of alpha- and beta-keratins. Epidermis and molts from adult individuals of an ancient reptilian species, the tuatara (Sphenodon punctatus), were analysed by immunocytochemistry, mono- and bi-dimensional electrophoresis, and western blotting for alpha-and beta-keratins. The epidermis of this reptilian species with primitive anatomical traits should represent one of the more ancient amniotic epidermises available. Soft keratins (AE1- and AE3-positive) of 40–63 kDa and with isoelectric points (pI) at 4.0–6.8 were found in molts. The AE3 antibody was diffusely localised over the tonofilaments of keratinocytes. The lack of basic cytokeratins may be due to keratin alteration in molts, following corneification or enzymatic degradation of keratins. Hard (beta-) keratins of 16–18 kDa and pI at 6.8, 8.0, and 9.2 were identified using a beta-1 antibody produced against chick scale beta-keratin. The antibody also labeled filaments of beta-cells and of the mature, compact beta-layer. We have shown that beta-keratins in the tuatara resemble those of lizards and snakes, and that they are mainly basic proteins. These proteins replace cytokeratins in the pre-corneoum beta-layers, from which a hard, mechanically resistant corneoum layer is formed over scales. Beta-keratins may have both a fibrous and a matrix role in forming the hard texture of corneoum scales in this ancient species, as well as in more recently evolved reptiles.

We have developed X-ray refraction-based computed tomography (CT) that is able to visualize soft tissue in between hard tissue. The experimental system consists of Si(220) diffraction double-crystals and is called the DEI (diffraction-enhanced imaging) method, in which the object is located between the crystals and a CCD camera to acquire data as 360 X-ray images. The X-ray energy used was 17.5 keV. The algorithm used to reconstruct CT images was developed by A. Maksimenko and colleagues. We successfully visualized articular cartilage and the distribution of bone marrow, which are inner structures. Our method has much higher contrast compared to the conventional absorption-based CT system.

Although motile iridophores in the longitudinal stripes of neon tetra skin are under control of the sympathetic nervous system, they also respond to light directly and show circadian color changes. Using neon tetra skin, we found that the photoresponse of iridophores depends on light intensity, and that light near 500 nm is most effective. RT-PCR demonstrated the expression of mRNAs encoding rhodopsin and two kinds of cone opsins (Pi-green1 and Pi-green2) in neon tetra skin where the light-sensitive iridophores exist. These mRNAs are also expressed in the lateral eyes. The cone opsin genes, Pi-green1 and Pi-green2, show high similarity with the g101 and g103 genes of unique green cone opsins (belonging to the MWS/LWS group) of the blind Mexican cavefish. These results show that Pi-green1, Pi-green2, and/or rhodopsin may play important roles in the photoresponse of neon tetra iridophores, which are most sensitive to light near 500 nm.

Three new megophryid species, Leptolalax melanoleucus, L. fuliginosus, and L. solus, are described from southwestern and southern Thailand on the bases of acoustic and morphological characteristics. Leptolalax melanoleucus and L. fuliginosus are similar to L. pelodytoides from northern Thailand, but differ from it completely in advertisement call characteristics and ventral color. Leptolalax solus is similar to L. heteropus from peninsular Malaysia, but differs from it by advertisement call, as well as by some body proportions. The distributional pattern of Leptolalax within Thailand is discussed.