Putting the cart before the horse: claims for mirror self-recognition in horses are unfounded Gordon G. Gallup Jr.James R. Anderson Commentary 27 July 2021 Pages: 1 - 4
Quantitative abilities of invertebrates: a methodological review Elia GattoOlli J. LoukolaChristian Agrillo Review Open access 19 July 2021 Pages: 5 - 19
Are you my mummy? Long-term olfactory memory of mother’s body odour by offspring in the domestic cat Péter SzencziAndrea UrrutiaOxána Bánszegi Short Communication 26 July 2021 Pages: 21 - 26
Quantity discrimination in a spontaneous task in a poison frog Sunil KhatiwadaSabrina S. Burmeister Short Communication 28 July 2021 Pages: 27 - 32
Visual snake aversion in Octodon degus and C57BL/6 mice Shigeru WatanabeHenning ScheichKazutaka Shinozuka Original Paper 22 June 2021 Pages: 33 - 41
Dogs (Canis lupus familiaris) are susceptible to the Kanizsa’s triangle illusion Miina LõokeLieta MarinelliPaolo Mongillo Original Paper Open access 16 July 2021 Pages: 43 - 51
African elephants can detect water from natural and artificial sources via olfactory cues Matthew WoodSimon Chamaillé-JammesAdrian M. Shrader Original Paper 22 July 2021 Pages: 53 - 61
Habituation in anuran tadpoles and the role of risk uncertainty Mariana PuetaDolores ArdanazJuan Cruz Tallone Original Paper 24 July 2021 Pages: 63 - 72
Positional inference in rhesus macaques Greg JensenVincent P. FerreraHerbert S. Terrace Original Paper 24 July 2021 Pages: 73 - 93
Domestic cats (Felis catus) prefer freely available food over food that requires effort Mikel M. DelgadoBrandon Sang Gyu HanMelissa J. Bain Original Paper Open access 26 July 2021 Pages: 95 - 102
Effects of early noise exposure on hippocampal-dependent behaviors during adolescence in male rats: influence of different housing conditions Sonia Jazmín MolinaÁngel Emanuel LiettiLaura Ruth Guelman Original Paper 28 July 2021 Pages: 103 - 120
Evaluating the accuracy of facial expressions as emotion indicators across contexts in dogs A. BremhorstD. S. MillsS. Riemer Original Paper Open access 02 August 2021 Pages: 121 - 136
Is this love? Sex differences in dog-owner attachment behavior suggest similarities with adult human bonds Biagio D’AnielloAnna ScandurraPaolo Mongillo Original Paper Open access 05 August 2021 Pages: 137 - 148
All units are equal in humpback whale songs, but some are more equal than others Eduardo Mercado IIIChristina E. Perazio Original Paper 06 August 2021 Pages: 149 - 177
Group size, partner choice and collaborative actions in male Indo-Pacific bottlenose dolphins (Tursiops aduncus) Eszter MatraiShaw Ting KwokÁkos Pogány Original Paper 07 August 2021 Pages: 179 - 193
The “right” side of sleeping: laterality in resting behaviour of Aldabra giant tortoises (Aldabrachelys gigantea) Caterina SpiezioCamillo SandriBarbara Regaiolli Original Paper Open access 09 August 2021 Pages: 195 - 203
How visual system configuration can play a role in individual recognition: a visual modeling study Rebecca TrappEsteban Fernández-Juricic Original Paper 12 August 2021 Pages: 205 - 216
Who is there? Captive western gorillas distinguish human voices based on familiarity and nature of previous interactions Roberta SalmiCaroline E. JonesJodi Carrigan Original Paper 14 August 2021 Pages: 217 - 228
Correction to: How visual system configuration can play a role in individual recognition: a visual modeling study Rebecca TrappEsteban Fernández-Juricic Correction 29 October 2021 Pages: 229 - 229