Large-brained birds display lower extra-pair paternity     

Yating LIU  Zhengjun WU  Wenbo LIAO 《Integrative zoology》2023,18(2):278-288

Extra-pair paternity (EPP) benefits to improve the reproductive success via extra-pair fertilizations without the costs of parental care in males and through improved offspring quality with additional food and parental care in females among species of birds. Variations in the EPP appear to link to behavioral and ecological factors and sexual selection. According to the “relationship intelligence hypothesis”, the cognitive abilities of the birds play an important role in maintaining long-term relationships. Here, we undertook the first comparative test of the relationships between extra-pair paternity and brain size, testis size, and life histories among 315 species of birds using phylogenetically controlled comparative analyses and path analysis. After controlling for the effects of shared ancestry and body mass, the frequency of EPP was negatively correlated with relative brain size, but positively with testis size across species of birds. However, the frequency of EPP was not linked to life-history traits (e.g. incubation period, fledging period, clutch size, egg mass, and longevity). Our findings suggest that large-brained birds associated with enhanced cognitive abilities are more inclined to maintain long-term stable relationships with their mates and to mutualism with them than to increase the frequency of EPP.  相似文献   

黑斑侧褶蛙脑微血管内皮细胞的原代培养及鉴定          下载免费PDF全文

艾单寒  侯家昊  刘芳园  顾泽茂  胡瑞雪 《水产学报》2023,47(8):089408-089408

为了建立蛙脑微血管内皮细胞原代培养方法，实验以黑斑侧褶蛙脑组织为实验材料，在无菌条件下分离出大脑灰质，利用0.1%Ⅱ型胶原酶和胶原酶-分散酶进行消化，经过Percoll密度梯度离心后，将获取的脑微血管段接种于鼠尾胶包被的培养瓶中，于28°C、5%CO₂条件下原代培养蛙脑微血管内皮细胞，并通过细胞形态学观察和Ⅷ因子相关抗原免疫荧光对细胞进行鉴定，最后用四唑蓝比色法(MTT)测定细胞的生长状态。结果显示，微血管段在体外培养1 d后开始贴壁生长，并逐渐扩大成团簇状，培养至7 d时，细胞呈“铺石路样”镶嵌式排列，表现为区域性单层生长；Ⅷ因子免疫荧光检测发现胞质呈红色，表达为阳性，阳性细胞率达97%以上；MTT实验显示，细胞在第3～5天时生长速率最快。本研究首次建立了蛙脑微血管内皮细胞的原代培养与鉴定方法，为体外研究蛙类神经性疾病的发病机理奠定基础，也为相关药物的研发和筛选提供了细胞模型。  相似文献   

乡村人才回流:国内外经验与启示     

李莉  张俊 《北京农业职业学院学报》2022,(5):32-38

乡村人才回流是实现乡村人才振兴的重要发力方向。基于安徽省4 县村“两委”负责人的访谈调研，分析国内外人才回流乡村的主要经验。研究发现:当前中西部乡村人才主动回流的总体态势不明显，人才外流现象仍然较为严重。农地整治、乡村一二三产业融合、乡村更新以及城乡融合发展是发达国家实现人才流入乡村的主要举措，产业带动、能人治村和人力资本产权激励是国内促进乡村人才回流的主要模式。借鉴国内外典型经验，应该加快乡村农地整治，推进乡村产业链与人才链的深度融合，健全人才返乡激励机制，提升乡村公共服务水平，坚持党建引领能人治村，从而实现乡村人才振兴。  相似文献