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Avian literature on sibling recognition is rare compared to that developed by mammalian researchers. We compare avian and mammalian research on sibling recognition to identify why avian work is rare, how approaches differ and what avian and mammalian researchers can learn from each other. Three factors: (1) biological differences between birds and mammals, (2) conceptual biases and (3) practical constraints, appear to influence our current understanding. Avian research focuses on colonial species because sibling recognition is considered adaptive where 'mixing potential' of dependent young is high; research on a wider range of species, breeding systems and ecological conditions is now needed. Studies of acoustic recognition cues dominate avian literature; other types of cues (e.g. visual, olfactory) deserve further attention. The effect of gender on avian sibling recognition has yet to be investigated; mammalian work shows that gender can have important influences. Most importantly, many researchers assume that birds recognise siblings through 'direct familiarisation' (commonly known as associative learning or familiarity); future experiments should also incorporate tests for 'indirect familiarisation' (commonly known as phenotype matching). If direct familiarisation proves crucial, avian research should investigate how periods of separation influence sibling discrimination. Mammalian researchers typically interpret sibling recognition in broad functional terms (nepotism, optimal outbreeding); some avian researchers more successfully identify specific and testable adaptive explanations, with greater relevance to natural contexts. We end by reporting exciting discoveries from recent studies of avian sibling recognition that inspire further interest in this topic.  相似文献   

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刘建全 《生物多样性》2016,24(9):1004-1386
已有的各个物种概念对物种的认识类似盲人摸象, 只包含了物种的某一个方面; 而一个分化后期的成熟物种应涵盖了所有的物种概念。但是, 尚未到达分化后期的物种往往又已开始新一轮的物种分化; 自然中存在的多数“物种”处于分化路上。这种循环往复连续分化产生的物种, 存在种间生殖隔离不彻底、基因流频繁发生、网状进化突出等现象。此外, 对于不同的物种对, 最早开始分化的基因以及不同物种概念所要求的条件的分化顺序不是统一的, 而是随机的。定义一个适合所有“分化路上的物种”概念存在较大困难。但是, 应采用尽可能多的物种概念来界定分化路上的物种、发表新种和进行分类处理; 也应承认种间可能广泛存在不完全的生殖隔离和有限的基因流, 即有不属于两个物种群体的杂交或回交个体的存在。这样划分的物种比只依据一个物种概念认定的物种具有更高的客观性和科学性。  相似文献   

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本文考证了中国先秦时期到清末古籍中对“地衣”的解释;其中有共生学意义的“地衣”一词,是在清代李善兰的《植物学》一书中被提出的。  相似文献   

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贺林 《遗传》2015,37(6):613-614
2015年年初,美国总统奥巴马在国情咨文中提出了一个预算2.15亿美元的“精准医学计划”,希望以此“引领一个医学时代”。新闻一经发布,“精准医学”立刻成为了媒体和百姓嘴边的热词,受此影响国内亦有不少人士纷纷为美国总统的这一计划点“赞”。有人用“医学革命”来形容它,有人用“开创性”来抬高它,还有一个传闻,受奥巴马“精准医学计划”的影响,中国将在15年内投入600亿元人民币启动并发展中国版的“精准医学计划”。对此,有人提出了质疑,美国版精准医学计划是否符合中国国情?是否存在“水土不服”的可能?直接套用美国总统的智慧能否解决具有中国特色的实际问题?争论由此引发一个让人思考的问题,究竟什么才是现代医学的核心?在盲目堆钱的行动前,我们确实有必要从科学和临床应用的角度来探讨和思考一下现代医学的发展方向。 为了能“精准”地看到问题的实质,我将从当下时髦并且相关的词汇谈起,通过梳理,期待找出解决人类健康问题的真正钥匙。  相似文献   

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Receptor‐subtype selectivity is an important issue in medicinal chemistry and can become very difficult to achieve if the actual binding pockets of the respective receptors are highly conserved. For such cases, known unselective ligands could be equipped with a spacer that sticks outside the actual orthosteric binding pocket towards the extracellular loops. The end of the spacer bears certain functional groups to enable specific or unspecific interactions with the receptor residues outside the binding cavity. Our experiments indicated that it is possible to achieve selectivity within the dopamine D1 family with such ‘loop‐hooks’.  相似文献   

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Metallothioneins (MTs) are ubiquitous cysteine-rich proteins present in plants, animals, fungi and cyanobacteria. In plants, MTs are suggested to be involved in metal tolerance or homeostasis, as they are able to bind metal ions through the thiol groups of their cysteine residues. Recent reports show that MTs are also involved in the scavenging of reactive oxygen species (ROS). The interplay between these roles is not entirely clear. Plants have many MT isoforms with overlapping expression patterns, and no specific role for any of them has been assigned. This review is focused on recent findings on plant MTs.  相似文献   

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香菇‘申香1644’是以传统优质栽培品种‘申香215’为亲本,采用多孢自交育种技术选育的新品种。其菌盖纵切面呈凸形,菌盖直径(6.15±0.38) cm,菌盖厚度(2.27±0.42) cm,菇型圆整,菇质紧实,产量高,生物学转化率95%以上。与亲本相比,‘申香1644’在分子标记和栽培性状上均具有明显差异性,其菌盖为浅黄褐色,颜色较亲本浅;菌龄100-105 d,较亲本缩短5-10 d。‘申香1644’菌丝生长适宜温度为22-26 ℃,原基发育适宜温度为16-22 ℃,可在全国范围内进行代料栽培。  相似文献   

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The question raised in the title was answered. (3R, 3'S)-meso-Zeaxanthin was submitted to iodine catalyzed photochemical stereoisomerisation. The enantiomeric (9Z) and (9'Z) geometrical isomers were isolated by semipreparative HPLC and separated as diastereomeric dicarbamates on a chiral column only. Cleavage of the carbamate could not be effected. CD-Spectra of (1"S, 1"S)- and (1"R, 1"R)-dicarbamates of geometrical isomers of (3R, 3'R)- and (3R, 3'S)-meso-zeaxanthin were systematically studied and the contribution from the carbamate moieties revealed. It was concluded that (9Z, 3R, 3'S)-"meso"-zeaxanthin, in spite of having no symmetry elements, is optically inactive. The result has been rationalised in line with the current hypothesis on the origin of carotenoid CD spectra.  相似文献   

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黄倩  邴健  岳慧珍  黄广华  魏羽佳 《菌物学报》2018,37(10):1278-1286
耳念珠菌Candida auris也被称为“超级真菌”,是近年来出现的一种人体病原真菌新物种,临床分离株通常具有多重耐药和高致死率等特征。2009年日本首次报道耳念珠菌之后,其感染病例在多个国家呈现出爆发式增长。目前已报道的病例分布在全球五大洲27个国家,包括中国。耳念珠菌感染给临床诊断和防控以及人类健康带来了巨大的挑战。本文从该菌临床分离菌株的生物学、遗传变异分化及耐药特征等方面入手,围绕分子流行病学、基因组特征、毒性因子和耐药性等方面系统地综述了近年来国内外取得的相关进展,并探讨了我国耳念珠菌感染的诊断、治疗和预防的措施。  相似文献   

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"灵芝"一词最早出现于东汉,人们"以为瑞草,服之神仙",称之为"灵芝"。现指隶属于真菌界Fungi、担子菌门Basidiomycota、伞菌纲Agaricomycetes、多孔菌目Polyporales、灵芝科Ganodermataceae的一类传统药用真菌的统称,具有免疫调节、抗肿瘤、抗氧化、抑菌、保肝护肝、止咳平喘等多种功效(林志彬2015;Gilletal.2016;Ahmad2018;Wuetal.  相似文献   

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杜适普  郭杰  刘小奎  张君  姜宇  王炯  孙水娟 《菌物学报》2022,41(7):1137-1139
‘豫香2号’是从河南省卢氏县伏牛山地区采集的野生香菇子实体,经过多次组织分离和驯化等系统选育而获得的优良品种,适宜河南省中高海拔区域种植。该品种子实体中等,多单生,菌盖圆整、浅褐色,菌柄呈倒圆锥形,产量高,鲜销耐储存。  相似文献   

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姚春馨  王晖  姚远  孙跃明  田果廷 《菌物学报》2021,40(6):1586-1588
‘高原云耳2号’由采自云南省普洱市景东县哀牢山的一株野生黑木耳多次分离和反复驯化,通过连续6年的系统选育、评价筛选而育成。该品种为中早熟、广温广适型新品种。子实体多单生,小口出耳单片率高,耳片厚、大小适中、边缘圆整、质地硬脆,背面青灰至灰黑色、腹面黑色、有光泽,耳脉少,平均产量55-65g/袋,商品性佳,抗性强。适于1 500-2 200m高海拔地区立体袋栽。  相似文献   

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Range shifts of tropical marine species to temperate latitudes are predicted to increase as a consequence of climate change. To date, the research focus on climate‐mediated range shifts has been predominately dealt with the physiological capacity of tropical species to cope with the thermal challenges imposed by temperate latitudes. Behavioural traits of individuals in the novel temperate environment have not previously been investigated, however, they are also likely to play a key role in determining the establishment success of individual species at the range‐expansion forefront. The aim of this study was to investigate the effect of shoaling strategy on the performance of juvenile tropical reef fishes that recruit annually to temperate waters off the south east coast of Australia. Specifically, we compared body‐size distributions and the seasonal decline in abundance through time of juvenile tropical fishes that shoaled with native temperate species (‘mixed’ shoals) to those that shoaled only with conspecifics (as would be the case in their tropical range). We found that shoaling with temperate native species benefitted juvenile tropical reef fishes, with individuals in ‘mixed’ shoals attaining larger body‐sizes over the season than those in ‘tropical‐only’ shoals. This benefit in terms of population body‐size distributions was accompanied by greater social cohesion of ‘mixed’ shoals across the season. Our results highlight the impact that sociality and behavioural plasticity are likely to play in determining the impact on native fish communities of climate‐induced range expansion of coral reef fishes.  相似文献   

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