{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,22]],"date-time":"2026-10-22T23:52:03Z","timestamp":1792713123061,"version":"4.5.0"},"reference-count":43,"publisher":"National Academy of Sciences","issue":"28","license":[{"start":{"date-parts":[[2026,7,6]],"date-time":"2026-07-06T00:00:00Z","timestamp":1783296000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"MOST | National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["3241101230"],"award-info":[{"award-number":["3241101230"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100011730","name":"Templeton World Charity Foundation","doi-asserted-by":"publisher","award":["TWCF0539"],"award-info":[{"award-number":["TWCF0539"]}],"id":[{"id":"10.13039\/501100011730","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Guangdong-Hong Kong Joint Laboratory for Psychiatric Disorders","award":["2023B1212120004"],"award-info":[{"award-number":["2023B1212120004"]}]},{"DOI":"10.13039\/501100001809","name":"MOST | National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["32371135"],"award-info":[{"award-number":["32371135"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Guandong Basic and Applied Basic Research Foundation","award":["2023A1515012168"],"award-info":[{"award-number":["2023A1515012168"]}]},{"name":"Guangzhou Science and Technology Planning Project","award":["2025A04J5255"],"award-info":[{"award-number":["2025A04J5255"]}]}],"content-domain":{"domain":["www.pnas.org"],"crossmark-restriction":true},"short-container-title":["Proc. Natl. Acad. Sci. U.S.A."],"published-print":{"date-parts":[[2026,7,14]]},"abstract":"<jats:p>Facial expressions provide a critical window into the internal states of animals, allowing the identification of affective processes and their underlying neural mechanisms. In mammals, postconsumption orofacial reactions\u2014such as tongue protrusions to sweet tastes\u2014are among the most robust and widely accepted behavioral markers of positive hedonic impact (liking), distinct from motivation (wanting). However, no equivalent markers have been established in insects, leaving their capacity for affective evaluation unresolved. Here, we show that bumblebees exhibit discrete orofacial reactions that are functionally analogous to those described in mammals. Bees displayed postconsumption glossa protrusions to rewarding solutions and head-shaking and mouth-wiping to aversive tastes. These reactions were not tied to any specific taste identity. Behavioral and pharmacological experiments demonstrated that glossa protrusions did not automatically occur due to consumption, were independent of ongoing feeding mechanisms and dopamine-mediated motivation, and were enhanced by the endocannabinoid anandamide. Our findings support postconsumption glossa protrusions as a fast, reliable, and evolutionarily comparable candidate behavioral marker of affective evaluation in an invertebrate. By providing evidence that a behavior which tracks liking can be dissociated from motivational (wanting) responsiveness in bumblebees, this work establishes an experimental framework for investigating the neural basis and evolutionary origins of affective processing. More broadly, these results open the door to rigorous cross-phyletic approaches to emotion.<\/jats:p>","DOI":"10.1073\/pnas.2529114123","type":"journal-article","created":{"date-parts":[[2026,7,6]],"date-time":"2026-07-06T19:09:56Z","timestamp":1783364996000},"update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":3,"title":["Bumblebees\u2019 orofacial reactions to tastes provide evidence for affective evaluation"],"prefix":"10.1073","volume":"123","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3324-9972","authenticated-orcid":false,"given":"Yonghe","family":"Zhou","sequence":"first","affiliation":[{"name":"State Key Laboratory of Multi-organ Injury Prevention and Treatment, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong-Hong Kong Joint Laboratory for Psychiatric Disorders, Guangdong Provincial Key Laboratory of Psychiatric Disorders, Guangdong Basic Research Center of Excellence for Integrated Traditional and Western Medicine for Qingzhi Diseases, Department of Psychiatry, Zhujiang Hospital, Southern Medical University","place":["Guangzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9754-4677","authenticated-orcid":false,"given":"Thomas","family":"Ingraham","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/00rqy9422","id-type":"ROR","asserted-by":"publisher"}],"name":"Office of the Deputy Vice Chancellor (Research and Innovation), The University of Queensland","place":["Brisbane, Australia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8135-6628","authenticated-orcid":false,"given":"Andrew B.","family":"Barron","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/01sf06y89","id-type":"ROR","asserted-by":"publisher"}],"name":"School of Natural Sciences, Macquarie University","place":["Sydney, Australia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1637-5611","authenticated-orcid":false,"given":"Fei","family":"Peng","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Multi-organ Injury Prevention and Treatment, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong-Hong Kong Joint Laboratory for Psychiatric Disorders, Guangdong Provincial Key Laboratory of Psychiatric Disorders, Guangdong Basic Research Center of Excellence for Integrated Traditional and Western Medicine for Qingzhi Diseases, Department of Psychiatry, Zhujiang Hospital, Southern Medical University","place":["Guangzhou, China"]},{"id":[{"id":"https:\/\/ror.org\/01vjw4z39","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Psychology, School of Public Health, Southern Medical University","place":["Guangzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2517-6179","authenticated-orcid":false,"given":"Cwyn","family":"Solvi","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Multi-organ Injury Prevention and Treatment, Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong-Hong Kong Joint Laboratory for Psychiatric Disorders, Guangdong Provincial Key Laboratory of Psychiatric Disorders, Guangdong Basic Research Center of Excellence for Integrated Traditional and Western Medicine for Qingzhi Diseases, Department of Psychiatry, Zhujiang Hospital, Southern Medical University","place":["Guangzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"341","published-online":{"date-parts":[[2026,7,6]]},"reference":[{"key":"e_1_3_4_1_2","doi-asserted-by":"publisher","DOI":"10.1146\/annurev-neuro-111020-103314"},{"key":"e_1_3_4_2_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.conb.2021.01.003"},{"key":"e_1_3_4_3_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0149-7634(99)00072-X"},{"key":"e_1_3_4_4_2","doi-asserted-by":"publisher","DOI":"10.3389\/fpsyg.2018.01647"},{"key":"e_1_3_4_5_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.cobeha.2022.101226"},{"key":"e_1_3_4_6_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.1817066116"},{"key":"e_1_3_4_7_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.cub.2011.05.017"},{"key":"e_1_3_4_8_2","doi-asserted-by":"publisher","DOI":"10.1098\/rsbl.2024.0228"},{"key":"e_1_3_4_9_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.applanim.2007.03.007"},{"key":"e_1_3_4_10_2","first-page":"20240512","article-title":"Physically stressed bees expect less reward in an active choice judgement bias test","volume":"291","author":"Procenko O.","year":"2024","unstructured":"O. 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