{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,22]],"date-time":"2026-05-22T18:06:17Z","timestamp":1779473177303,"version":"3.53.1"},"reference-count":44,"publisher":"Public Library of Science (PLoS)","issue":"5","license":[{"start":{"date-parts":[[2026,5,22]],"date-time":"2026-05-22T00:00:00Z","timestamp":1779408000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"PRIN 2017","award":["2017PSRHPZ"],"award-info":[{"award-number":["2017PSRHPZ"]}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p>In research on animal numerical cognition, newly hatched domestic chicks have been shown to rely on distinct strategies when confronted with quantitative choices. In some conditions, such as after imprinting on a specific set of objects, chicks preferentially approach the larger set of familiar items, indicating sensitivity to magnitude. In other conditions, however, their responses are governed not by magnitude per se, but by the degree of similarity between the test objects and a previously experienced set, where similarity is defined in terms of conformity to specific perceptual constraints, such as the possibility of a symmetrical division into identical subsets (as in composite versus prime sets of items). In the present study, we sought to replicate both phenomena while aligning key methodological features, including the test arena, the comparison (5 vs. 9), and the age at testing. One group of chicks was imprinted on a set of identical objects to test preference for larger familiar set; another group was habituated to even-numbered sets to assess sensitivity to perceptual asymmetry in prime-numbered ones. We successfully replicated both effects: chicks preferred the larger set after imprinting and showed longer inspection of the prime-numbered set after habituation, despite its smaller magnitude. Our results show that different mechanisms supporting quantity discrimination are available from the earliest stages of life and can be triggered by task- or environment-specific factors.<\/jats:p>","DOI":"10.1371\/journal.pone.0349870","type":"journal-article","created":{"date-parts":[[2026,5,22]],"date-time":"2026-05-22T17:31:56Z","timestamp":1779471116000},"page":"e0349870","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Distinct early-life mechanisms of quantity discrimination in domestic chicks"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0024-2670","authenticated-orcid":true,"given":"Maria","family":"Loconsole","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elisa","family":"Tedaldi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lucia","family":"Regolin","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2026,5,22]]},"reference":[{"key":"pone.0349870.ref001","volume-title":"The number sense: How the mind creates mathematics, revised and updated edition","author":"S Dehaene","year":"2011"},{"issue":"1","key":"pone.0349870.ref002","doi-asserted-by":"crossref","first-page":"16","DOI":"10.1111\/1468-0017.00154","article-title":"Pr\u00e9cis of the number sense","volume":"16","author":"S Dehaene","year":"2001","journal-title":"Mind & Language"},{"issue":"7","key":"pone.0349870.ref003","doi-asserted-by":"crossref","first-page":"605","DOI":"10.1016\/j.tree.2020.02.009","article-title":"The adaptive value of numerical competence","volume":"35","author":"A Nieder","year":"2020","journal-title":"Trends Ecol Evol"},{"key":"pone.0349870.ref004","doi-asserted-by":"crossref","first-page":"379","DOI":"10.1006\/anbe.1994.1052","article-title":"Roaring and numerical assessment in contests between groups of female lions, Panthera leo","volume":"47","author":"K McComb","year":"1994","journal-title":"Anim Behav"},{"issue":"1649","key":"pone.0349870.ref005","first-page":"2373","article-title":"Adaptive numerical competency in a food-hoarding songbird","volume":"275","author":"S Hunt","year":"2008","journal-title":"Proc Biol Sci"},{"key":"pone.0349870.ref006","doi-asserted-by":"crossref","first-page":"271","DOI":"10.1007\/BF00163984","article-title":"Safety in numbers: Shoal size choice by minnows under predatory threat","volume":"29","author":"MC Hager","year":"1991","journal-title":"Behav Ecol Sociobiol"},{"issue":"1740","key":"pone.0349870.ref007","doi-asserted-by":"crossref","first-page":"20160509","DOI":"10.1098\/rstb.2016.0509","article-title":"Towards numerical cognition\u2019s origin: Insights from day-old domestic chicks","volume":"373","author":"R Rugani","year":"2017","journal-title":"Philos Trans R Soc Lond B Biol Sci"},{"issue":"1740","key":"pone.0349870.ref008","doi-asserted-by":"crossref","first-page":"20160511","DOI":"10.1098\/rstb.2016.0511","article-title":"Understanding the origin of number sense: A review of fish studies","volume":"373","author":"C Agrillo","year":"2017","journal-title":"Philos Trans R Soc Lond B Biol Sci"},{"issue":"1740","key":"pone.0349870.ref009","doi-asserted-by":"crossref","first-page":"20160518","DOI":"10.1098\/rstb.2016.0518","article-title":"From number sense to number symbols. 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