====== Captivity ======

Captivity, frequently used in [[animal research]], can profoundly alter brain size, cognitive abilities and [[activity]] levels. Critically, persistent exposure to stressors in captive [[environment]]s can lead to chronic [[stress]] and subsequently to a range of health issues. However, the direct implications of captivity on research outcomes have not been thoroughly investigated. 

Baldoni et al. examined the effects of captivity on the common shrew, Sorex araneus, a species that exhibits a profound seasonal reversible change in [[brain]] and body size. They compared wild shrews during summer and winter to assess seasonal changes in brain size and behaviour and then contrasted these findings with shrews kept in captivity for six months. Using repeated in vivo [[magnetic resonance imaging]], they determined that the extent of seasonal [[brain]] size change was not affected by the semi-natural captive conditions. However, captivity led to increased activity levels and reduced learning motivation in the shrews, indicative of chronic [[stress]]. These results suggest that even semi-natural conditions can significantly alter the outcome of studies and these effects need to be quantified before experimentation
((Baldoni C, Raptis K, Farantouri M, Lenzi I, Lim KS, Menz MHM, Muturi M, Reisert M, Bedoya Duque MA, Thomas WR, Dávalos LM, Nieland JD, von Elverfeldt D, Dechmann DKN. Captivity alters behaviour but not seasonal brain size change in semi-naturally housed shrews. R Soc Open Sci. 2025 Mar 5;12(3):242138. doi: 10.1098/rsos.242138. PMID: 40420851; PMCID: PMC12105801.)).