Treatment with beta2-adrenoceptor agonist in vivo induces human clock gene, Per1, mRNA expression in peripheral blood

This study examined whether in vivo exposure to a β₂-adrenoceptor agonist, tulobuterol, induces human Period1 (hPer1) mRNA expression in cells from peripheral whole blood. In one experiment, oral tulobuterol was administered to five healthy volunteers at 22:00 h, while in another, a transdermally tulobuterol patch was applied to the same five subjects at 20:00 h. In each experiment, serum tulobuterol concentrations were measured at four time points, and total RNA was isolated from peripheral blood cells for determinations of hPer1 mRNA expression by real-time polymerase chain reaction. Both the tulobuterol tablet and the transdermal patch increased hPer1 mRNA expression, suggesting that analyses of human peripheral blood cells could reliably represent peripheral clock gene mRNA expression in vivo.     

Pollination biology of a disjunct population of the endangered sandhills endemic <Emphasis Type="Italic">Penstemon haydenii</Emphasis> S. Wats. (Scrophulariaceae) in Wyoming,USA

We studied the breeding system and flower visitors of the endangered plant, Penstemon haydenii, at several south-central Wyoming, USA occurrences. In agreement with earlier studies of the species 300 km to the east in Nebraska, we found Wyoming plants to be self-incompatible and pollinator-dependent for sexual reproduction. Flower visitors were several species of native bees in the families Apidae (particularly bumblebees), Halictidae (small sweat bees), and Megachilidae (especially in the genus Osmia); and the masarid wasp Pseudomasaris vespoides. Especially important was Osmia brevis, an abundant megachilid bee, and one of only two species (the sweat bee Lasioglossum (Dialictus) pruinosum was the other) present at all five sites. As in Nebraska, fruit set did not differ between our experimental cross-pollination treatment and an open-pollinated control. However, unlike Nebraska, open-pollinated treatments in Wyoming produced significantly fewer seeds per fruit than the experimental out-crossing treatment. We discuss several possible explanations for seed limitation: (1) a scarcity of pollinators early in the flowering season; (2) resource competition for developing ovules on open-pollinated inflorescences but not on experimental inflorescences; (3) the deposition of self pollen through intra-inflorescence and intra-genet pollinator movements; (4) few S-alleles and mating types in the Wyoming metapopulation compared to the Nebraska metapopulation, from which it likely derives.     

Investigating human responses to political and environmental change through paleodiet and paleomobility

Bioarchaeological approaches are well suited for examining past responses to political and environmental changes. In the Andes, we hypothesized that political and environmental changes around AD 1100 resulted in behavioral changes, visible as shifts in paleodiet and paleomobility, among individuals in the San Pedro de Atacama oases and Loa River Valley. To investigate this hypothesis, we generated carbon and oxygen isotope data from cemeteries dating to the early Middle Horizon (Larache, Quitor‐5, Solor‐3), late Middle Horizon (Casa Parroquial, Coyo Oriental, Coyo‐3, Solcor‐Plaza, Solcor‐3, Tchecar), and Late Intermediate Period (Caspana, Quitor‐6 Tardío, Toconce, Yaye‐1, Yaye‐2, Yaye‐3, Yaye‐4). Carbon isotope data demonstrate a greater range of carbon sources during the late Middle Horizon compared with the Late Intermediate Period; while most individuals consumed largely C₃ sources, some late Middle Horizon individuals consumed more C₄ sources. Oxygen isotope data demonstrate greater diversity in drinking water sources during the late Middle Horizon compared with the Late Intermediate Period. Water samples were analyzed to provide baseline data on oxygen isotope variability within the Atacama Desert, and demonstrated that oxygen isotope values are indistinguishable in the San Pedro and Loa Rivers. However, oxygen isotope values in water sources in the high‐altitude altiplano and coast are distinct from those in the San Pedro and Loa Rivers. In conclusion, instead of utilizing a wider variety of resources after environmental and political changes, individuals exhibited a wider range of paleodietary and paleomobility strategies during the Middle Horizon, a period of environmental and political stability. Am J Phys Anthropol 157:179–201, 2015. © 2015 Wiley Periodicals, Inc.     

Reproductive biology of the horned viper,Cerastes cerastes gasperettii in the central region of Saudi Arabia

The reproductive biology of the horned viper, Cerastes cerastes gasperettii, in Riyadh region of Saudi Arabia was investigated over a period of one year. Study of reproductive cycle of male and female C. c. gasperettii revealed that the breeding season is relatively short (April and May). Thereafter females laid eggs by mid of July and hatching probably had taken place by the end of September. No activity was observed during winter, this may indicate just a single clutch per year. Relative testis weight to body weight was drastically increased (X¯ = 0.88%) during the peak of reproductive activity (May) where maximal expansion of seminiferous tubules was also attained during April and May (X¯ = 209 μm and 191 μm, respectively). Likewise, the ovarian activity was the highest during May where ovarian parameters were greater in terms of relative ovarian weight to body weight and ova diameter being 0.46% and 2.29 mm, respectively. Fat body weight was increased drastically just before the peak of reproductive activity then started to decline during June. It could be concluded that the harsh desert conditions and similar environments certainly affect reproductive activity of Saudi Arabian reptiles including snakes.     

The importance of reproductive interference in ecology and evolution: from organisms to communities

Knowledge of species interactions is vital to understand ecological and evolutionary patterns in nature. Traditional species interactions (e.g., competition, predation, symbiosis) have received a great deal of deserved attention and their general importance in shaping the evolution of populations and structure of communities is unquestioned. Recently, reproductive interference has been receiving attention as an important species interaction. Reproductive interference is defined as interspecific reproductive activities that decrease the fitness of at least one of the species involved in the interaction. Reproductive interference has the potential to affect the evolutionary trajectories of populations and structure of communities. Here, I comment on seven papers that make up this special feature on reproductive interference. Along the way I highlight key discoveries of these studies and areas of research that may contribute to our understanding of the causes and consequences of reproductive interference.     

Functional morphology of the male caudal appendages of the damselfly Ischnura elegans (Zygoptera: Coenagrionidae)

Odonata are usually regarded as one of the most ancient extant lineages of winged insects. Their copulatory apparatus and mating behavior are unique among insects. Male damselflies use their caudal appendages to clasp the female's prothorax during both copulation and egg-laying and have a secondary copulatory apparatus for sperm transfer. Knowledge of the functional morphology of the male caudal appendages is the basis for understanding the evolution of these structures in Odonata and respective organs in other insects. However, it is still not exactly known how the zygopteran claspers work. In this study, we applied micro-computed tomography and a variety of microscopy techniques to examine the morphology, surface microstructure, cuticle material composition and muscle topography of the male caudal appendages of Ischnura elegans. The results indicate that the closing of the paraproctal claspers is mainly passive. This indirect closing mechanism is very likely supported by high proportions of the elastic protein resilin present in the cuticle of the paraproctal bases. In addition, the prothoracic morphology of the female plays an important role in the indirect closing of the male claspers. Our data indicate that both structures – the male claspers and the female prothoracic hump – function together like a snap-fastener.     

Reproductive performance and milk traits of F1 Romanov ewes

The objective of this study was to evaluate the effect of crossbreeding Awassi and Morkaraman ewes with Romanov sires on litter size and total productivity as reflected by reproductive performance and milk production in the ewes. Twenty-three Romanov × Awassi (RA) and 19 Romanov × Morkaraman (RM) ewes were used. All of the ewes were pregnant at the start of the study, and litter size at birth and at weaning (60 days) were recorded. Milk production was recorded weekly and milk composition was estimated as dry matter and fat percentage. Litter size at birth (RM: 1.89 ± 0.18; RA: 1.62 ± 0.15) and weaning (RM: 1.67 ± 0.20; RA: 1.46 ± 0.17), dam weight at lambing (RM: 50.2 ± 2.37; RA: 44.2 ± 1.98) and total productivity (RM: 29.9 ± 3.05; RA: 24.4 ± 2.54) were not influenced by breed-type. Lactation length and milk yield was relatively but not significantly higher in RA than RM ewes. Dry matter and fat percentage of milk were found to be similar for both breed-types. Results of the present study indicate that crossbreeding of Awassi and Morkaraman ewes with Romanov rams yielded similar performance in F1 ewes. When F1 ewe performance is compared with their pure breed maternal ancestor, it is concluded that reproductive performance is improved by crossbreeding with Romanov.     

Population genomics and speciation in yeasts

The advent of efficient whole genome sequencing and the large molecular and genetic toolbox available for studies in Saccharomyces cerevisiae and related species have allowed unprecedented analysis of big issues such as: what causes reproductive isolation and eventual speciation? The species complex encompassing S. cerevisiae and relatives consists of six species and several naturally occurring hybrids, which have nearly collinear genomes. They fit the biological species definition of within species fertility and between species sterility. There are examples of chromosome rearrangements and of genetic incompatibilities between species of the complex, which contribute to reproductive isolation but these are not universally present. In addition, simple sequence divergence has been shown to cause reproductive isolation via the action of the mismatch repair system. Although all three of these mechanisms contribute to extant reproductive isolation, which if any, drive the speciation process is still an open question. Population genomic surveys of whole genome sequences reveal introgressions and horizontal gene transfers between species, indicating that the species barriers are not complete. This gene flow between species, although infrequent, brings into question the nature of yeast species.     

罗氏沼虾繁殖行为的再描述

2007年6～9月对采自孟加拉国库尔纳专区羌纳县布苏尔河原产地罗氏沼虾(Macrobrachium rosenbergii)的繁殖行为进行了观察研究。配合摄像机录像技术,重点观察并记录了野生罗氏沼虾生殖过程中的主要行为特征。本文所涉及的繁殖过程特指在人工操控条件下,自两性遭遇、识别至雌虾抱卵为止这段时间。选择体重在80.0g以上的雄虾、40.0g以上的雌虾分别在当地河堤外侧的池沼中驯化适应15d,然后,在室内水泥池中观察其繁殖行为。罗氏沼虾在繁殖过程中呈现的典型行为主要有:两性遭遇及识别,雄虾的占位,雌虾的蜕壳,雄虾俘获雌虾及其交媾前的守卫、交媾及精荚传递,雄虾交媾后的守卫及释放雌虾,雌虾产卵及抱卵。其中,雄虾的配偶守卫行为是有效地保证两性生殖成功的交配策略之一。