杜鹃对两种远距离的近缘苇莺的巢寄生:一个平行协同进化的案例?(英文)

大杜鹃(Cuculus canorus)通常寄生小型雀形目鸟类。由于杜鹃雏鸟的排他性拱卵或拱雏,导致宿主繁殖失败,因此宿主进化出如卵识别能力的反寄生策略。反过来,杜鹃也同时进化出如模拟宿主卵的寄生策略。于是两者之间的相互作用可形成类似军备竞赛的协同进化关系。在匈牙利,大苇莺(Acrocephalus arundinaceus)是大杜鹃的主要宿主,寄生率可高达约 40-65%。以往被认为是大苇莺一个亚种的东方大苇莺(A. orientalis)在日本的种群也被大杜鹃寄生(25-40%)。通过采用光纤光谱仪量化大杜鹃及其宿主的卵色特征,我们比较了东、西半球大杜鹃对两种苇莺的寄生模拟程度。鸟类视觉模型显示,对于可见光颜色,杜鹃与宿主之间卵色的模拟程度在匈牙利高于日本,但匈牙利杜鹃和宿主均较大的卵色变异程度可导致卵色模拟困难。杜鹃与苇莺卵色的量度差异在日本较低,这被证明是宿主拒卵行为的一个重要影响因素。苇莺对大杜鹃卵的拒绝率在日本(35%)和匈牙利(37%)相似。与匈牙利不同,在日本,宿主对杜鹃寄生的应对策略如拒卵行为,先于杜鹃的反适应对策。我们认为,两种近缘物种大苇莺对杜鹃寄生的不同反寄生行为,代表了协同进化军备竞赛的不同演化阶段。     

Improving the floral attractant to lure <Emphasis Type="Italic">Epicometis hirta</Emphasis> Poda (Coleoptera: Scarabaeidae,Cetoniinae)

In order to improve the efficiency of the known floral attractant of Epicometis hirta [(E)-anethol and (E)-cinnamyl alcohol in a ratio of 1:1], candidate synergist compounds for field tests were selected through electroantennographic tests using the antennae of female and male E. hirta adult beetles. Among synthetic floral compounds 4-methoxyphenethyl alcohol and methyl salicylate evoked high responses from the antennae and were chosen for further field studies. In trapping tests in Bulgaria, the addition of 4-methoxyphenethyl alcohol to the E. hirta bait in the ratio of 1:1:1, in Hungary in ratios of 1:1:0.3 and 1:1:1 significantly increased catches. The addition of methyl salicylate was without effect in both countries. A high-capacity trap supplied with this ternary attractant could be more efficient for mass trapping purposes of E. hirta in environment-friendly plant protection.     

Application of anti-BCG antibody for rapid immunohistochemical detection of bacteria, fungi and protozoa in formalin-fixed paraffin-embedded tissue samples

The applicability of an anti-Mycobacterium bovis (BCG) antibody-based immunohistochemistry (IHC) procedure was investigated using everyday veterinary pathological samples collected from 13 different animal species. Fifty-one formalin-fixed and paraffin-embedded tissue samples were selected for this study. Forty, 4 and 7 tissue samples contained different species of bacteria, fungi and protozoa, respectively. Three serial sections were prepared in each case. Two sections were pre-treated with enzyme and heat, respectively, while the last section was not pre-treated. In seven cases the sensitivity of histochemical staining (HSM), IHC and bacteriological culture were compared. Heating of the sections in a microwave oven was the most effective method in the case of almost all pathogens used. Strong or moderate positive reactions were observed for 26 bacterial species, all fungal and 2 protozoal species, while weak reactions occurred for 2 bacterial and 1 protozoal species. Only 4 protozoal and 12 bacterial species, including Leptospira and all the five Mycoplasma species examined, showed no reaction in this test. IHC had almost the same sensitivity as bacteriological culture and was more sensitive than HSM. The IHC method presented here should be preferred to HSM as a general screening tool in cases where pathological lesions suspicious for infections are evident and no microorganism can be cultured in vitro or only formalin-fixed tissue samples are available for the laboratory examination.     

The general ecological model of the Slovak Socialist Republic — Methodology and contents

Development of the general ecological model (EM) of the CSSR has been included in the state program for environmental policy - the Ecoprogramme of the CSSR — at a scale of 1:1 000 000 for the entire Czechoslovak territory and at a scale of 1:500 000 for the Czech Socialist Republic (CSR) and the Slovak Socialist Republic (SSR). The objective of the first EM stage was to make a survey of spatial differentiation of the major ecological problems of the country. The EM consists of four parts, three analytical and one synthetic. These parts are:

1. The ecological state (value) of the current spatial structure of the landscape.
2. Ecological stress factors in the landscape.
3. Protection of nature and natural resources. From the spatial synthesis of these three groups (from their spatial encounters), the following synthetic group of conditions was obtained:
4. Regional ecological problems, a system of ecologically stable areas, environmental stress factors and factors endangering the ecological stability of the landscape, the natural resources and the human environment.

     

Evolutionary approach to communication between humans and dogs

Dogs and humans have been sharing a common environment for a long time. Some aspects of their social interaction are described as communication in which members of both species influence each other’s behaviour by special behaviour signals. Recent research is aimed at providing an evolutionary account for the emergence of communicative interactions between dogs and people. The present review summarizes how carefully applied experimental methods can be utilised to answer such research questions, in order to separate different processes that may underlie the mental abilities in dogs.     

Transient interface sharpening in miscible alloys

We observed that diffuse interfaces sharpen rather than broaden in completely miscible ideal binary systems. This is shown in situ during heat treatments at gradually increasing temperatures by scattering of synchrotron radiation in coherent Mo/V multilayers containing initially diffuse interfaces. This effect provides a useful tool for the improvement of interfaces and offers a way to fabricate better x-ray or neutron mirrors, microelectronic devices, or multilayers with giant magnetic resistance.     

Effect of diets with different inclusion levels of distillers dried grain with solubles combined with lysine and methionine supplementation on the lipid peroxidation and glutathione status of chickens

To study the possible effects of different inclusion levels of distillers dried grain with solubles (DDGS) on the lipid peroxidation and glutathione redox status of chickens, 200 three-week-old Ross 308 cockerels were assigned to four treatment groups of 50 birds each. The groups were fed a control and three experimental, isocaloric and isonitrogenous grower diets containing 15, 20 and 25% DDGS, respectively, combined with lysine (Lys) and methionine (Met) supplementation until 6 weeks of age. It was found that DDGS inclusion increased the ether extract content of the diets which resulted in higher reduced glutathione (GSH) content and elevated glutathione peroxidase activity (GSHPx) in the liver. However, DDGS addition with Lys and Met supplementation did not influence the malondialdehyde content of the blood and the liver. The oleic acid proportion of the diet showed a close positive correlation with GSH content of the liver. A smaller ratio of methionine and cysteine in the diet with DDGS resulted in significantly higher liver GSH content. GSHPx activity increased parallel with the elevated GSH content of the liver homogenate, suggesting that the enzyme is activated by the actual supply of its co-substrate. In conclusion, the results show that DDGS, even at a high inclusion level combined with Lys and Met supplementation, has no initiative effect on lipid peroxidation in the blood and liver of broiler chickens.     

Infants' perseverative search errors are induced by pragmatic misinterpretation

Having repeatedly retrieved an object from a location, human infants tend to search the same place even when they observe the object being hidden at another location. This perseverative error is usually explained by infants' inability to inhibit a previously rewarded search response or to recall the new location. We show that the tendency to commit this error is substantially reduced (from 81 to 41%) when the object is hidden in front of 10-month-old infants without the experimenter using the communicative cues that normally accompany object hiding in this task. We suggest that this improvement is due to an interpretive bias that normally helps infants learn from demonstrations but misleads them in the context of a hiding game. Our finding provides an alternative theoretical perspective on the nature of infants' perseverative search errors.