Collaborative Research: Social brains and solitary bees: A phylogenetic test of the effect of social behavior on brain evolution across multiple gains and losses of sociality

合作研究：社交大脑和独居蜜蜂：社会行为对大脑进化影响的系统发育测试，涉及社交性的多种得失

• 批准号: 1755375
• 负责人: Adam Smith
• 金额: $ 35.13万
• 依托单位: George Washington University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-04-01 至 2024-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1755375&HistoricalAwards=false
• 关键词: Collaborative; Research; Social; brains; solitary

How do social interactions drive brain size? Living in a social group with other animals may require a bigger brain in order to deal with the cognitive challenge of maintaining social relationships. Alternatively, animals in social groups may have smaller brains because members of social groups can work together, thus reducing the cognitive challenge faced by each individual. This research will measure brain size in closely related species of social and solitary bees. Social cooperation has evolved many times in bees, and has also been lost many times: some solitary bees evolved from social ancestors. This project will also measure levels of neurotransmitters and hormones in bee brains that are associated with aggression and reproduction. Scientists still do not have a clear understanding of how even relatively simple brain differences are associated with the evolution of complex behavioral traits. This research will use the small brains of bees and the multiple comparisons between many different social and solitary species to investigate how living in a cooperative social group affects the brain. The scientists involved in the project will mentor students through internships in their labs, and will write versions of their research publications aimed at middle- and high-school aged students that will be made freely available on the web for education and outreach. This project tests the hypothesis that the evolution of social cooperation leads to increased brain size. This research focuses on measuring changes in the volume of the mushroom body (an area of the insect brain), and biogenic amines of the brains of social and solitary bees. The researchers focus on the sweat bees (Halictidae) because this group is ancestrally solitary with three evolutionary origins of sociality and multiple evolutionary losses from within the social clades. Also, many species are socially polymorphic, exhibiting both social and solitary behavior. This allows for multiple phylogenetically independent social-solitary comparisons. The researchers focus on mushroom body volume because this area of the brain is used for learning, memory, and sensory integration. They measure biogenic brain amines because these chemicals are involved in regulating aggressive, social, and reproductive behavior, and thus likely involved in the evolution of social cooperation. Lastly, they test whether changes in levels of brain amines are mechanistically linked to changes in brain size, and also measure changes in amine receptor density associated with social behavior. This work uses a phylogenetic comparative approach, confocal microscopy measurements of brain volume, high performance liquid chromatography (HPLC) measurements of amine titers, and antibody staining of amine-reactive neurons to test how evolutionary gains and losses of social cooperation affect the brain. This work addresses issues of broad public appeal - brain evolution and cooperation. As part of the broader impacts of this project, researchers will work with professional editors to create open-access adaptations of their studies for use in classrooms or other educational or outreach purposes. They will also train graduate and undergraduate students across five different institutions.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

社交互动如何影响大脑大小？与其他动物生活在社会群体中可能需要更大的大脑来应对维持社会关系的认知挑战。另外，社会群体中的动物可能有较小的大脑，因为社会群体的成员可以一起工作，从而减少每个个体面临的认知挑战。这项研究将测量密切相关的群居蜜蜂和独居蜜蜂物种的大脑大小。蜜蜂的社会合作经历过多次进化，也多次消失：一些独居蜜蜂是从社会祖先进化而来的。 该项目还将测量蜜蜂大脑中与攻击和繁殖相关的神经递质和激素水平。科学家们仍然不清楚，即使是相对简单的大脑差异如何与复杂行为特征的进化相关。这项研究将利用蜜蜂的小大脑以及许多不同社会和孤独物种之间的多重比较来研究生活在合作社会群体中如何影响大脑。 参与该项目的科学家将通过在实验室实习来指导学生，并将撰写针对初中和高中学生的研究出版物，这些出版物将在网络上免费提供，用于教育和宣传。该项目测试了社会合作的进化导致大脑尺寸增加的假设。这项研究的重点是测量蘑菇体（昆虫大脑的一个区域）体积的变化，以及群居和独居蜜蜂大脑中的生物胺。研究人员将重点放在汗蜂（Halictidae）身上，因为该群体在祖先中是孤独的，具有三个社会性的进化起源，并且在社会分支内部经历了多次进化损失。此外，许多物种具有社会多态性，表现出社会行为和孤独行为。这允许进行多个系统发育独立的社会孤独比较。研究人员关注蘑菇的体积，因为大脑的这个区域用于学习、记忆和感觉统合。他们测量生物脑胺，因为这些化学物质参与调节攻击性、社会性和生殖行为，因此可能参与社会合作的进化。最后，他们测试了脑胺水平的变化是否与大脑大小的变化在机制上相关，并且还测量了与社会行为相关的胺受体密度的变化。这项工作使用系统发育比较方法、共焦显微镜测量大脑体积、高效液相色谱 (HPLC) 测量胺滴度以及胺反应神经元的抗体染色来测试社会合作的进化得失如何影响大脑。这项工作解决了广泛公众关注的问题——大脑进化与合作。作为该项目更广泛影响的一部分，研究人员将与专业编辑合作，对他们的研究进行开放获取的改编，以用于课堂或其他教育或推广目的。他们还将培训五个不同机构的研究生和本科生。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

A split sex ratio in solitary and social nests of a facultatively social bee

兼性群居蜜蜂的独居巢穴和群居巢穴中性别比例的分裂

• DOI: 10.1098/rsbl.2018.0740
• 发表时间: 2019
• 期刊: Biology Letters
• 影响因子: 3.3
• 作者: Smith, Adam R.;Kapheim, Karen M.;Kingwell, Callum J.;Wcislo, William T.
• 通讯作者: Wcislo, William T.

Decline of native bees (Apidae: Euglossa) in a tropical forest of Panama

巴拿马热带森林中本土蜜蜂（蜜蜂科：Euglossa）的衰落

• DOI: 10.1007/s13592-020-00781-2
• 发表时间: 2020
• 期刊: Apidologie
• 影响因子: 2.4
• 作者: Vega-Hidalgo, Álvaro;Añino, Yostin;Krichilsky, Erin;Smith, Adam R.;Santos-Murgas, Alonso;Gálvez, Dumas
• 通讯作者: Gálvez, Dumas

Small Body Size Is Associated with Increased Aggression in the Solitary Sweat Bee Nomia melanderi (Hymenoptera, Halictidae)

体型较小与独居汗蜂Nomia melanderi（膜翅目，Halictidae）的攻击性增加有关

• DOI: 10.1007/s10905-019-09736-7
• 发表时间: 2019
• 期刊: Journal of Insect Behavior
• 影响因子: 1
• 作者: Smith, Adam R.;DeLory, Timothy;Johnson, Makenna M.;Figgins, Anna C.;Hagadorn, Mallory A.;Kapheim, Karen M.
• 通讯作者: Kapheim, Karen M.

Queen–worker aggression in the facultatively eusocial bee Megalopta genalis

兼性群居蜂 Megalopta genalis 中蜂王与工蜂的攻击行为

• DOI: 10.1007/s00040-019-00712-0
• 发表时间: 2019
• 期刊: Insectes Sociaux
• 影响因子: 1.3
• 作者: Smith, A. R.;Simons, M.;Bazarko, V.;Harach, J.;Seid, M. A.
• 通讯作者: Seid, M. A.

Survival and productivity benefits of sociality vary seasonally in the tropical, facultatively eusocial bee Megalopta genalis

热带兼性社会性蜜蜂 Megalopta genalis 的社会性生存和生产力效益随季节变化

• DOI: 10.1007/s00040-019-00713-z
• 发表时间: 2019
• 期刊: Insectes Sociaux
• 影响因子: 1.3
• 作者: Smith, A. R.;Kapheim, K. M.;Wcislo, W. T.
• 通讯作者: Wcislo, W. T.