再引入黑颈长尾雉育雏行为和育雏地选择

2004～2005年在广西岑王老山自然保护区对再引进黑颈长尾雉的育雏行为和育雏地选择进行了研究.结果表明:雏鸟活动能力随时间明显增强,1～3日活动面积在300 m2以内.育雏初期为地栖,后期开始为树栖.育雏地有3种类型:人工西南桦幼林、针叶林、针阔混交林.3种生境的乔木盖度分别是75%、90%、85%;草本盖度分别是80%、60%、65%.Mann-Whitney U分析表明草本层盖度,水源距离,林缘距离,林间小路距离是影响黑颈长尾雉育雏地选择的主要因子.     

Fluctuations in incubation temperature affect incubation duration but not morphology,locomotion and growth of hatchlings in the sand lizard Lacerta agilis (Lacertidae)

Li, H., Zhou, Z.‐S., Ding, G.‐H. and Ji, X. 2011. Fluctuations in incubation temperature affect incubation duration but not morphology, locomotion and growth of hatchlings in the sand lizard Lacerta agilis (Lacertidae). —Acta Zoologica (Stockholm) 00 : 1–8. Studies looking for potential effects of temperature and temperature fluctuations on phenotypic traits of reptile hatchlings have shown species variation, but have not always allowed a distinction between effects of fluctuation per se and temperature extremes themselves. To examine whether incubation temperature fluctuation has a key role in influencing the phenotype of offspring, we incubated eggs of the sand lizard Lacerta agilis at one of the four temperature regimes (27, 27 ± 2, 27 ± 4 and 27 ± 6 °C). We found that: (1) hatchlings incubated under the four temperature regimes did not differ from each other in any of the morphological and physiological traits examined; (2) interactions that included temperature treatment did not affect any trait examined; (3) the mean incubation length was longer in the 27 ± 6 °C treatment than in the other three treatments; and (4) female hatchlings were shorter in head length and width but longer in snout‐vent length as well as abdomen length than males derived from the same‐sized egg. Our data show that both the type and the magnitude of temperature variation can affect incubation length. We found no evidence for phenotypic divergence in responses to temperature fluctuations during incubation and therefore suggest that temperature variation does not affect the phenotype of hatchlings in L. agilis.     

湖南主要经济蛇类养殖场的设计与建造调查研究

目的研究出一种适合湖南地域理想的科学经济蛇类人工养殖场。方法采用调查研究法、试验法、归纳总结法等研究方法。结果总结出湖南省经济蛇类养殖场主要有蛇房、露天蛇场、室内外结合蛇场等3种模式,首创了“湖南立体蛇场”模式。结论在湖南省境内采用“湖南立体蛇场”模式进行经济蛇类的养殖效果较好,不仅简单易建、经济合算,而且科学合理、实用方便,达到了预期的目的。     

Renesting and brooding in the Caribbean flamingo

Caribbean flamingos were observed during the 1981 breeding season at the Audubon Zoological Garden in New Orleans, Louisiana. Two floods occurred during the breeding season, causing the flock to nest three times. At each new nesting there was a significant decline in the number of birds laying eggs. One pair brooded a chick during the final nesting. Immediately after hatching, the female usually brooded while the male defended the nest area; however, over the three-day period that the chick remained on the nest, the male began to spend more time brooding and less time defending the nest area. Thus there appeared to be some division of labor in this flamingo pair.     

Innate phase behavior in the desert locust,Schistocerca gregaria

Abstract Detailed aspects of the transition from the solitarious to the gregarious phase in the framework of locust ecology are undoubtedly most important for understanding locust phase polyphenism. Nevertheless, due to obvious difficulties in studying the solitarious phase in nature, such information is limited and mostly available from research carried out under laboratory conditions. In the current study, we examined the dispersal patterns of newly hatched locust nymphs in a laboratory setup that simulated seminatural conditions. This was carried out with no previous manipulation of the nymphs other than controlling their parental density. We comparatively tested the spatial distribution of newly hatched nymphs on perches located at different ranges within an emergence arena, and the expected Poisson (random) distribution. Hatchlings were found to disperse among the perches in a pattern significantly different from that expected by random. Irrespective of their parents’ phase, the observed distributions of all nymphs were clearly clumped, similar or close to those expected for gregarious locusts. It seems that rather than emerging with a parentally derived and predetermined phase, hatchlings have an independent default or innate behavioral state, which reflects at least tolerance if not attraction to conspecifics. The typical phase behavior may later become dominant under the appropriate environmental conditions. These results imply novel perspectives on locust phase transformation, which contribute to our understanding of the formation of locust crowds under field conditions. These should be considered in any rationale for developing a preventative management strategy of locust populations.     

Evolution of pelagic direct development in the starfish Pteraster tesselatus (Asteroidea: Velatida)

Despite a diversity of larval forms, remarkably conservative features of asteroid development define a larval body plan that occurs throughout the class. However, recent work on the starfish Pteraster tesselatus has documented a highly derived pattern of development. Several features, including radial symmetry, parallel embryonic and adult axes of symmetry, absence of a preoral lobe, and formation of coeloms in the adult orientation from seven separate enterocoels, have not been reported in asteroids before. The complete absence of the larval body plan features that are found in other asteroids, indicates that P. tesselatus develops directly from the embryo to the juvenile and has a pelagic, nonfeeding (lecithotrophic), but nonlarval mode of development. I postulate that direct development evolved over an extended period in a lineage of brooding, deep-sea velatid (probably pterastcrid) ancestors of P. tesselatus. Selection for increased developmental efficiency (loss of nonfunctional larval features) in the brooded offspring, could explain the lack of larval settlement structures, the nonlarval arrangement of coeloms, the lack of a preoral lobe, the transverse orientation of the juvenile disc, and the lack of bilateral symmetry. The pattern of coclomogenesis could have been derived from that of other velatids (e.g. solasterids) by relatively simple changes in timing and orientation of entcroeoel formation. Rotation and posterior translation of the coelomic fate map of the archenteron prior to enlerocoel formation would produce the coelomic compartments in the adult orientation that characterizes direct development in P. tesselatus. These unusual developmental features lead to a radically different interpretation for the evolution of the pelagic ‘larva’ of P. tesselatus: (1) evolution of benthie brooding, (2) extreme simplification of development involving the loss of all larval features from the life cycle, and (3) subsequent re-evolution of pelagic development. In the case of P. tesselatus, where all larval structures were lost, there do not seem to be functional constraints preventing the re-evolution of pelagic development. Analysis of pelagic and benthie larvae, in other asteroids, suggests that major ecological transitions in life histories need not be associated with substantia] changes in morphology. The loss of pelagic development should have occurred repeatedly and should be readily reversible. These findings have interesting implications for the loss and evolution of pelagic dispersal in the life histories of marine benthie invertebrates.     

Developmental pathways of anthozoans

Stage of propagule release from female parent, and site of development and nutritive mode of embryo are the factors used here to define developmental pathways of anthozoans. Nearly every possible combination of variables of the 3 factors exists, forming a mosaic. Further, a larva may experience serially more than one development site, and may derive nutrition serially or simultaneously from more than a single source. Thus, no fundamental patterns appear to exist. This is probably due to the simplicity of cnidarians, which constrains their development far less than that of other animals.