Kinship alters the effects of forced cohabitation on body weight,mate choice and fitness in the rat-like hamster Tscheskia triton

It has been documented that social isolation imparts deleterious effects on gregarious rodents species, but caging in group imparts such effects on solitary rodents. This study was attempted at examining how kinship to affect body weight, behavioral interaction, mate choice and fitness when we caged male and female rat-like hamsters Tscheskia triton in pair, a solitary species. We found that females paired with nonsibling males became heavier than the females paired with sibling males, but both agonistic and amicable behavior between paired males and females did not differ between sibling and nonsibling groups. This indicated that kinship might reduce females＇ obesity in response to forced cohabitation, and dissociation might exist between physiological and behavioral responses. Furthermore, binary choice tests revealed that social familiarity between either siblings or nonsiblings decreased their investigating time spent in opposite sex conspeeifie of cage mates and/or their scents as compared with those of nonmates, suggesting effects of social association on mate and kin selection of the hamsters. On the other side, both females and males caged in pair with siblings show a preference between unfamiliar siblings or their scents and the counterparts of nonsiblings after two month separation, indicating that the kin recognition of the hamsters might also rely on phenotype matching. In addition, cohabitation （or permanent presence of fathers） elicited a lower survival of pups in nonsibling pairs than sibling pairs, but did not affect litter size, suggesting that kinship affects fitness when housing male and female ratlike hamsters together. Therefore, inbreeding might be adapted for rare and endangered animals.     

The impact of attractants on pocket gopher trapping

Pocket gophers （Geomyidae） have an extensive impact on both natural and agricultural systems. Trapping is a tech- nique often used to sample and manage these populations. The identification of an attractant that increases capture rates of pocket gophers would greatly assist researchers and pest management professionals alike. Therefore, we tested the attractiveness of four attractants （peanut butter, anise, grapefruit attractant, and carrot） plus a control （no attractant） using uncovered and covered trap sets to determine what impact they have on visitation and capture rates of pocket gophers. We also determined how the impact of cover status and attractants differ across varying weights and gender of pocket gophers. We found no direct effect of any attracrant on visitation and capture rates of pocket gophers, nor on the gender of captured individuals. However, when no attractant was used, the mtmber of pocket gophers captured per 100 trap nights was greater when trap sets were uncovered vs. when covered, and capture rates were generally high and consistent when using peanut butter as an attractant. Additionally, we noted that covered trap sets that were baited with peanut butter yielded heavier pocket gopher captures than uncovered trap sets using this same attractant. This is key, given the difficulty associated with capturing older, more experienced individuals. Combined with data from a previous investigation, this suggests that there is no advantage to using any attractant when utilizing uncovered trap sets, but there is likely some benefit to using peanut butter in covered trap sets [Current Zoology 60 （4）： 472-478, 2014].     

Evolution of deceit by worthless donations in a nuptial gift-giving spider

Males of the nursery web spider Pisaura mirabil usually offer an insect prey wrapped in white silk as a nuptial gift to facilitate copulation. Males exploit female foraging preferences in a sexual context as females feed on the gift during copula- tion. It is possible for males to copulate without a gift, however strong female preference for the gift leads to dramatically higher mating success for gift-giving males. Females are polyandrous, and gift-giving males achieve higher mating success, longer copulations, and increased sperm transfer that confer advantages in sperm competition. Intriguingly, field studies show that ap- proximately one third of males carry a worthless gift consisting of dry and empty insect exoskeletons or plant fragments wrapped in white silk. Silk wrapping disguises gift content and females are able to disclose gift content only after accepting and feeding on the gift, meanwhile males succeed in transferring sperm. The evolution of deceit by worthless gift donation may be favoured by strong intra-sexual competition and costs of gift-construction including prey capture, lost foraging opportunities and investment in silk wrapping. Females that receive empty worthless gifts terminate copulation sooner, which reduces sperm transfer and likely disadvantages males in sperm competition. The gift-giving trait may thus become a target of sexually antagonistic co-evolution, where deceit by worthless gifts leads to female resistance to the trait. We discuss factors such as female mating rate and intensity of sperm competition that may shape the evolution of male deception, and how ecological factors may influence the evolution and maintenance of worthless gifts as an evolutionarily stable alternative mating strategy by frequency dependent selection     

Animal personality and the ecological impacts of freshwater non-native species

While the ecological impacts of invasive species have been demonstrated for many taxonomic groups, the potential effects of behavioural variation among nonnative individuals （i.e. personality） on these impacts have been largely overlooked. This is despite the fact that recent studies have demonstrated that, by nature, the three first stages of biological invasions （i.e. transport, establishment and spread） can lead to personalitybiased populations. Freshwater ecosystems provide a unique oppor tunity to investigate this issue, notably because the ecological impacts of nonnative species have been extensively documented and because animal personality has been widely studied using freshwater model species. Here, we aim at developing some per spectives on the potential effects of animal personality on the ecological impacts of freshwater nonnative species across levels of biological organizations. At the individual level, personality types have been demonstrated to affect the physiolo gy, metabolism, life history traits and fitness of individuals. We used these effects to discuss how they could subsequently impact invaded popula tions and, in turn, recipient communities. We also discussed how these might translate into changes in the structure of food webs and the functioning of invaded ecosystems. Finally we discussed how these perspectives could interact with the management of invasive species .     

Novel functions of GABA signaling in adult neurogenesis

Neurotransmitter gamma-aminobutiric acid （GABA） through ionotropic GABAA and metabotropic GABAB receptors plays key roles in modulating the development, plasticity and function of neuronal networks. GABA is inhibitory in mature neurons but excitatory in immature neurons, neuroblasts and neural stem/progenitor cells （NSCs/ NPCs）. The switch from excitatory to inhibitory occurs following the development of glutamatergic synaptic input and results from the dynamic changes in the expression of Na＋/K＋/2CF co-transporter NKCC1 driving CF influx and neuron-specific K＋/Cl co-transporter KCC2 driving Cl efflux. The developmental transition of KCC2 expression is regulated by Disrupted-in-Schizophrenia 1 （DISC1） and brain-derived neurotrophic factor （BDNF） signaling. The excitatory GABA signaling during early neurogenesis is important to the activity/experience-induced regulation of NSC quiescence, NPC proliferation, neuroblast migration and new-born neuronal maturation/functional integration. The inhibitory GABA signaling allows for the sparse and static functional networking essential for learning/memory development and maintenance.     

Evolutionary implications of deception in mimicry and masquerade

Aggressive mimicry occurs when an organism resembles some aspect of another organism （the model） in order to obtain prey through its deceptive resemblance. This may function either through the overt response of the receiver or through the lack of response of the receiver. Reviewing selected examples, I discuss some of the difficulties in ascribing a model for the mimic. I also discuss how a single animal can have multiple ploys in its armoury of deceptive signals, thus belonging within two or more categories of deceptive signalling. In addition to aggressive mimicry, these may include crypsis or camouflage, mas- querade （mimicry of inanimate objects）, and Batesian or protective mimicry. Each of these examples of deception has multiple evolutionary pathways, and some deceptive signals may be more costly to receivers than others, but no single organism is subject to a single selection pressure, leading to the reality that many evolutionary pathways contribute to the diversity we see around us. New technologies are opening new channels of investigation into deceptive signaling in many different sensory modalities, and this is reflected in the recent increase in studies investigating the structure and function of deceptive signals. In turn, these studies are beginning to expose the fascinating complexity of deceptive signaling systems, allowing us to discover the myriad, non-mutually exclusive, solutions that can be selected for to obtain prey     

Evolution of sexual size dimorphism and its relationship with sex ratio in carabid beetles of Genus Ceroglossus Solier

Although the degree of mate competition, given extreme differences in sex ratio, explains much of the pattern of male-biased size dimorphism among diverse taxa, it fails for some species which have potential for intense male competition for mates and yet exhibit little or no sexual size dimorphism （SSD）. This fact suggest that species with low SSD should be express the effect of evolutionary pressure in non-obvious geometrical shape promoted by sex ratio in an evolutionary time scale. To evaluate this hypothesis we used phylogenetic comparative method in a Bayesian framework to investigate the evolution of SSD and the role of sex ratio at inter-specific level in the species of Ceroglossus （Coleoptera： Carabidae）. In our results the proportion farthest from 1：1 is associated with more disparate body shape, even though the entire group has minimum variation in sex ratio, which is an intrinsic life history character of this group considering its phylogenetic conservatism or phylogenetic signal. We suggest that the sex ratio has determined the dimorphism degree during evolution of this group, since both traits have increased or decreased together during the species divergence （i.e. positive phylogenetic correlation： r2=0.85）. We suggest that morphological studies of SSD will benefit from using comparative method with Bayesian approaches to assess the effect of phylogenetic history and its uncertainty. Finally, this will be allow to researchers to quantify the uncertainty of specific evolutionary hypotheses accounting for observed sexual dimorphism patterns.     

Comparative analysis of chromosome segregation in human,yeasts and trypanosome

Chromosome segregation is a tightly regulated process through which duplicated genetic materials are equally partitioned into daughter cells. During the past decades, tremendous efforts have been made to understand the molecular mechanism of chromosome segregation using animals and yeasts as model systems. Recently, new insights into chromosome segregation have gradually emerged using trypanosome, an early branching parasitic protozoan, as a model organism. To uncover the unique aspects of chromosome segregation in trypanosome, which potentially could serve as new drug targets for anti-trypanosome chemotherapy, it is necessary to perform a comparative analysis of the chromosome segregation machinery between trypanosome and its human host. Here, we briefly review the current knowledge about chromosome segregation in human and Trypanosoma brucei, with a focus on the regulation of cohesin and securin degradation triggered by the activation of the anaphase promoting complex/cyclosome （APC/C）. We also include yeasts in our comparative analysis since some of the original discoveries were made using budding and fission yeasts as the model organisms and, therefore, these could provide hints about the evolution of the machinery. We highlight both common and unique features in these model systems and also provide perspectives for future research in trypanosome.     

Differential attraction of parasitoids in relation to specificity of kairomones from herbivores and their by-products

Infochemicals are used by foraging parasitoids in the host selection process from habitat preference until host recognition. Kairomones from the herbivore host plays a vital role in the attraction of parasitoids, particularly in the micro-habitat. Parasitoids are specifically attracted to their respective herbivore species even when different herbivores are present on the same plant. Chemicals emitted from different stages of host （eggs, larvae, pupae, adult）, host by-products （e.g., frass, exuviae, mandibular gland secretions, defense secretions etc.）, or intra-specific infochemicals （pheromones） can be main signals for the parasitoids. Parasitoids can differentiate between host and non-host, between different hosts and host stages by perceiving specific volatile and contact kairomones from the host itself, host along with its by-product, by-products alone or intra-specific infochemicals; of which frass （by-product） and intra-specific infochemicals are the most reported ones. Adult and larval parasitoids have been reported to be attracted to kairomones of their target stage or byproduct of their host. Pupal parasitoids have been found to utilize kairomones from the preceding host stage while egg parasitoids are known to exploit a variety of host infochemicals, for example, either from eggs themselves or other non-target host stages, especially adults and adult-related by-products. The kairomonal chemicals identified so far include various groups, but mainly hydrocarbons. A high degree of host specificity and host acceptance is important for the parasitoids as any mistake may result in the loss of fitness.     

Fine structural description of the compound eye of the Madagascar ＇hissing cockroach＇ Gromphadorhinaportentosa （Dictyoptera： Blaberidae）

The compound eyes of the wingless adults of the Madagascar ＇hissing cockroach＇ Gromphadorhinaportentosa Sachum, 1853 were examined by light and electron microscopy. Each eye contains 2 400-2 500 mostly hexagonal facets. However, irregularities affecting both shape and size of the ommatidia are relatively common, especially towards the margins of the eye. An individual ommatidium of this eucone type of apposition eye contains eight retinula cells, which give rise to a centrally-fused, tiered rhabdom. The distal end of the latter is funnel-shaped and accommodates the proximal end of the cone in its midst, Further below, the rhabdom （then formed by the rhabdomeres of four retinula cells） assumes a squarish profile with microvilli aligned in two directions at right-angle to each other. Cross sections through the proximal regions of the rhabdom display triangular rhabdom outlines and microvilli （belonging to 3-4 retinula cells different from those involved in the squarish more distal rhabdom） that run in three directions inclined to one another by 120°. Overall the organization of the eye conforms to the orthopteroid pattern and particularly closely resembles that of the American cockroach Periplaneta americana. However, since G. portentosa possesses fewer ommatidia, this could be a consequence of its inability to fly. On the other hand, the large size of the facets and the voluminous rhabdoms suggest considerable absolute sensitivity and an ability to detect the plane of linearly polarized light. Based on the pattern of microvillus orientations in combination with the crepuscular lifestyle G. portentosa leads and the habitat it occurs in, the prediction is made that this insect uses its green receptors for e-vector discrimination in the environment of down-welling light that reaches the forest floor.     

Using the movement patterns of reintroduced animals to improve reintroduction success

Despite their importance to conservation, reintroductions are still a risky endeavor and tend to fail, highlighting the need for more efficient post-release monitoring techniques. Reintroduced animals are released into unfamiliar novel environ ments and must explore their surroundings to gain knowledge in order to survive. According to theory, knowledge gain should be followed by subsequent changes to the animal＇s movement behavior, making movement behavior an excellent indicator of reintroduction progress. We aim to conceptually describe a logical process that will enable the inclusion of behavior （in particular, movement behavior） in management decision-making post-reintroductions, and to do so, we provide four basic components that a manager should look for in the behaviors of released animals. The suggested components are release-site fidelity, recurring locations, proximity to other individuals, and individual variation in movement behavior. These components are by no means the only possible ones available to a manager, but they provide an efficient tool to understanding animals＇ decision-making based on ecological theory; namely, the exploration-exploitation trade-off that released animals go through, and which underlies their behavior. We demonstrate our conceptual approach using data from two ungulate species reintroduced in Israel： the Persian fallow deer Dama mesopotamica and the Arabian oryx Oryx leucoryx [Current Zoology 60 （4）： 515-526, 2014] .     

Does defensive posture increase mimetic fidelity of caterpillars with eyespots to their putative snake models？

Organisms often evolve behaviours that increase or reinforce the protection from predators afforded by their morpho- logical defences. For example, mimetic animals may adopt postures or locomotory behaviours that emulate a characteristic fea- ture of their model to increase predator deception. Caterpillars with eyespots are thought to mimic snakes, and when threatened many of these caterpillars adopt a posture that appears to enhance this resemblance. Herein we evaluate the quantitative strength of evidence of behavioural mimicry in the caterpillars of 14 species by comparing how closely a series of putative snake-mimicking caterpillars resemble snakes while at rest and when threatened. Specifically, we quantified the head morphology and eye position of a range of snake species, as well as the shape of the apparent head （i.e. anterior body segments） and position of eyespots in caterpillars resting or in their defensive posture. This allowed us to objectively examine evidence for an increased resemblance to either snakes generally, or to Viperidae snakes specifically, upon adopting the defensive posture. Widening the anterior body segments during the defensive posture typically made caterpillars appear more viper-like as opposed to more snake-like in general. Enhanced resemblance to vipers upon mounting the defensive posture was apparent only from the dorsal view. Laterally, caterpillars more closely resembled snakes in the resting posture and shifting to the defensive posture instead reduced mimetic fidelity, Overall we found evidence for behavioural mimicry in all 14 species examined. We highlight that objectively quantifying mimetic fidelity can help identify key features involved in deception .     

异型雄蕊植物花内雄蕊的分化

Flowers that have heteromorphic stamens （heterantherous flowers） have intrigued many researchers ever since the phenomenon was discovered in the 19th century. The morphological differentiation in androecia has been suggested as a reflection of ＂labor division＂ in pollination in which one type of stamens attracts pollinators and satisfies their demand for pollen as food and the other satisfies the plant＇s need for safe gamete dispersal. The extent and patterns of stamen differentiation differ notably among taxa with heterantherous flowers. Seven species with heteromorphic stamens in three genera were sampled from Leguminosae and Melastomataceae, and the morphological difference of androecia, pollen content, pollen histochemistry and viability, pollen micro- morphology, as well as the main pollinators were examined and compared. Pollen number differs significantly between stamen sets of the same flower in most species investigated, and a correlation of pollen number and anther size was substantiated. Higher pollen viabilities were found in the long （pollinating） stamens of Senna alata （L.） Roxb. and S. bicapsularis （L.） Roxb. Dimorphic pollen exine ornamentation is reported here for the first time in Fordiophytonfaberi Stapf. The height of stigma and anther tips of the long stamens in natural conditions was proved to be highly correlated, supporting the hypothesis that they contact similar areas of the pollinator＇s body.     

The role of behavior in tern conservation

Behavioral research has long had an important role in the conservation of terns （Ayes： Stemidae）. Habitat management and restoration of breeding colony sites depends on knowledge of the cues used to select colony and nest sites. For example, conspecific attraction with playback and decoys is commonly used to bring terns to suitable colony sites and habitat modification is often used to increase the availability of suitable nest sites. Tern colonies are interconnected by dispersal, and a metapopulation approach is needed for effective management. Population dynamics are therefore affected by behaviors that influence the frequency of movement among colony sites： site fidelity, natal and breeding dispersal, and group adherence. The monogamous breeding system of terns should keep effective population size similar to census population size, but variation in sex ratios （likely resulting from sex differences in behavior） and in parental quality can result in a smaller than expected effective population size. In addition to the behavior of terns, knowledge of the behavior of predators on terns contributes to management plans, because predator behavior can sometimes be manipulated and predation is often performed by only a few specialized individuals. Other examples of links between tern behavior and conservation are also briefly reviewed, such as behavioral toxicology research and studies of behavioral responses to human disturbance and manmade structures. More work is needed on the behavior of migratory terns at staging sites, stopover sites and wintering grounds, and on the behavior of less well-studied species and species in less well-studied geographic regions [Current Zoology 60 （4）： 500-514, 2014].     

What is the sound of fear？ Behavioral responses of white-crowned sparrows Zonotrichia leucophrys to synthesized nonlinear acoustic phenomena

Fear and anxiety may be adaptive responses to life-threatening situations, and animals may communicate fear to others vocally. A fundamental understanding of fear inducing sounds is important for both wildlife conservation and management because it helps us understand how to design repellents and also how （and why） animals may be negatively impacted by anthropogenic sounds. Nonlinear phenomena--sounds produced by the desynchronization of vibrations in a sound production system-are commonly found in stress-induced animal vocalizations, such as in alarm calls, mobbing calls, and fear screams. There are several functional hypotheses for these nonlinear phenomena. One specific hypothesis is the unpredictability hypothesis, which suggests that because nonlinear phenomena are more variable and somewhat unpredictable, animals are less likely to habituate to them. Animals should, therefore, have a prolonged response to sounds with nonlinear phenomena than sounds without them. Most of the studies involving nonlinear phenomena have used mammalian subjects and conspecific stimuli. Our study fo- cused on white-crowned sparrows （Zonotrichia leucophrys ssp. oriantha） and used synthesized acoustic stimuli to investigate behavioral responses to stimuli with and without nonlinear phenomena. We predicted that birds would be less relaxed after hearing a stimulus with a nonlinear component. We calculated the difference from baseline of proportion of time spent in relaxed behaviors and performed pair-wise comparisons between a pure tone control stimulus and each of three experimental stimuli, including a frequency jump up, a frequency jump down, and white noise. These comparisons showed that in the 30q50 s after the playback experiment, birds were significantly less relaxed after hearing noise or an abrupt frequency jump down an octave but not an abrupt frequency jump up an octave or a pure tone. Nonlinear phenomena, therefore, may be generally arousing to animals and may explain why these acoustic properties are commonly fou     

Unhatched and Hatched Eggshells of the Chinese Cobra Naja atra

Changes in structure and composition of the eggshell resulting from embryonic mobilization of minerals from the eggshell are found in all oviparous reptiles studied thus far. In this study, we measured samples of unhatched and hatched eggshells of the Chinese cobra Naja atra to determine the percentage of ash and the phase composition of calcium carbonate. The mean percentage of ash was significantly higher in unhatched eggshells （24.6%） than in hatched eggshells （22.3%）. The dominant phase in unhatched eggshells was the calcite form of calcium carbonate. In addition to the peaks of calcite, a few small peaks were found to be caused by the aragonite and vaterite phases of calcium carbonate, implying that there are small amounts of aragonite and vaterite in the eggshell. The concentration of the various phases calculated from the intensity of the X-ray diffraction spectra allowed the estimation that percentages of calcite, aragonite and vaterite were about 92%, 4% and 4%, respectively. Hatched eggshells produced similar spectral characteristics as unhatched eggshells, with one exception. The dominant phase composition in the hatched eggshell was also calcite, but the amount of the aragonite phase had a marked increase. Our study adds evidence that embryonic mobilization of minerals from the eggshell may result in changes in structure of the eggshell.     

Differences in Incubation Length and Hatchling Morphology among Five Species of Oviparous Phrynocephalus Lizards （Agamidae） from China

We incubated eggs of five Phrynocephalus species （P. albolineatus, P. axillaries, P. grumgrzimailoi, P. helioscopus and P. przewalskii） at three constant temperatures （24℃, 28℃ and 32℃） to examine differences in incubation length and hatchling morphology among species and among temperature treatments. We combined data from this study with those reported previously for P. frontalis and P. versicolor to examine whether embryonic stage at laying is a causal factor for interspecific variation in incubation length, and whether the phylogenetic relationship inferred from hatchling morphology is consistent with the relationship based on mitochondrial DNA data. Mean values for incubation length differed among the five species studied herein and, in all these five species, incubation length decreased at a decreasing rate as temperature increased. In none of the five species did hatchling size （snout-vent length and body mass） and other morphological variables differ among the three temperature treatments. The seven oviparous Phrynocephalus lizards found in China differ from each other in hatchling morphology, and embryonic stage at laying is a causal factor of inter- and intra-specific variation in incubation length. The phylogenetic relationship inferred from hatchling morphology is not always consistent with the currently known relationship based on mitochondrial DNA data. Data from this study and those reported previously allow the conclusion that any Phrynocephalus species may have its unique position along the axis defined by hatchling morphology.     

Use of a dietary exposure system for screening of insecticidal compounds for their toxicity to the planthopper Laodelphax striatellus

We developed a dietary exposure assay for screening insecticidal compounds for their toxicity and for assessing the side effects of insecticidal proteins produced by genetically engineered （GE） plants on the planthopper Laodelphax striatellus Fallen. The fitness bioassay confirmed that the diet fulfills the requirements to be used in the dietary exposure system. To validate the efficacy of the dietary exposure system, nymphs of L. striatellus were fed diets treated with different concentrations of an inorganic stomach poison, potassium arsenate （PA）, or a cysteine protease inhibitor, E-64. The results showed that with increasing concentrations of E-64, the larval development time was prolonged, the adult weight was reduced and the survival rate of L. striatellus was decreased. Similarly the survival rates of L. striatellus consistently decreased with increasing PA content in the diet. The data indicate that the dietary exposure assay is able to detect the effects of insecticidal compounds on L. striatellus. Subsequently, this assay was successfully used for assessing the potential toxicity of Cry2Aa. The results showed that L. striatellus larvae were not negatively affected when fed the artificial diet containing purified Cry2Aa at 300 μg/g diet. In the assay, the stability and bioactivity of crystal （Cry） proteins in the food sources were confirmed by enzyme-linked immunosorbent assay and sensitive-insect bioassays. These results show that L. striatellus is not sensitive to Cry2Aa. We conclude that the dietary exposure system is valid and useful for assessing the toxicity of insecticidal compounds produced by GE plants on planthoppers.     

The dichotomy of p53 regulation by noncoding RNAs

The p53 tumor suppressor gene is the most frequently mutated gene in cancer. Significant progress has been made to discern the im- portance of p53 in coordinating cellular responses to DNA damage, oncogene activation, and other stresses. Noncoding RNAs are RNA molecules functioning without being translated into proteins. In this work, we discuss the dichotomy of p53 regulation by noncoding RNAs with four unconventional questions. First, is overexpression of microRNAs responsible for p53 inactivation in the absence of p53 mutation？ Second, are there somatic mutations in the noncoding regions of the p53 gene？ Third, is there a germline mutant in the non- coding regions of the p53 gene that predisposes carriers to cancer？ Fourth, can p53 activation mediated by a noncoding RNA mutation cause cancer？ This work highUghts the prominence of noncoding RNAs in p53 dysregutation and tumorigenesis.     

Effect of Incubation Temperature on the Somatic Development of the Snail-Eating Turtle Malayemys macrocephala

The rising average global temperature can lead to changes both in the physical and biological environments and affect the survival of organisms. Freshwater turtles are considered to be susceptible species since their development is dependent on incubation temperature. In Thailand, although several species of freshwater turtle are present, the extent of their susceptibility to temperature change is unknown due to the lack of information on their developmental patterns. This research, therefore, is aimed at examining the effects of temperature on somatic development in Malayemys macrocephala, a native species and the most common freshwater turtle in Thailand. Turtle eggs were collected from rice fields in the central part of Thailand during December 2011 to February 2012 inclusive. Eggs （237-238 per condition） were incubated in microprocessor-controlled incubators at three different temperatures （26 ℃, 29℃ and 32℃） with a relative humidity in excess of 80%. Each week, until the remaining eggs hatched, eggs were randomly selected, removed and dissected to reveal the developing embryo to screen for developmental stage and any abnormalities. The incubation period （lay to hatch） was not significantly different among the three temperatures （115 ±11.3 d, 115 ±20.3 d and 109±17.8 d, respectively）, but the growth patterns, as indicated by the stages of development and carapace lengths, were significantly different. At a high temperature （32℃）, turtle embryos showed a significantly faster growth rate than at the intermediate and low temperatures （29 ℃and 26 ℃）, but had a significantly （over 3.3-fold） higher incidence of developmental abnormalities （especially deformed bodies） than at the lower temperatures. Overall, the results indicate that incubation temperature is an important variable affecting the somatic development of this tropical freshwater turtle species, whilst abnormalities in the embryonic body may be a sensitive indicator of extreme thermal stress.