The minds of reptiles remain largely mysterious to us, and we often wonder what kind of emotions they are capable of feeling. In this episode we dig into a new study which tries to uncover some of the mysteries of tortoise cognition, particularly whether they can experience different moods. We follow that up with a newly described species of lizard from the rocky deserts of Arabia.

Main Paper References:

Hoehfurtner T, Wilkinson A, Moszuti SA, Burman OHP. 2025. Evidence of mood states in reptiles. Animal Cognition 28. DOI: 10.1007/s10071-025-01973-y.

Species of the Bi-Week:

Šmíd J, Velenská D, Pola L, Tamar K, Busais S, Shobrak M, Almutairi M, Salim AFA, Alsubaie SD, AlGethami RHM, AlGethami AR, Alanazi ASK, Alshammari AM, Egan DM, Ramalho RO, Olson D, Smithson J, Chirio L, Burger M, Van Huyssteen R, Petford MA, Carranza S. 2025. Phylogeny and systematics of Arabian lacertids from the Mesalina guttulata species complex (Squamata, Lacertidae), with the description of a new species. BMC Zoology 10. DOI: 10.1186/s40850-025-00233-3.

Other Mentioned Papers/Studies:

Harding EJ, Paul ES, Mendl M. 2004. Cognitive bias and affective state. Nature 427:312–312. DOI: 10.1038/427312a.

Moszuti SA, Wilkinson A, Burman OHP. 2017. Response to novelty as an indicator of reptile welfare. Applied Animal Behaviour Science 193:98–103. DOI: 10.1016/j.applanim.2017.03.018.

Other Links/Mentions:

Alamshah AL, Marshall BM. 2025. Big bills, small changes: with few exceptions, Jungle crows show minor variation in bill morphology across their distribution. EcoEvoRxiv. DOI: 10.32942/X2NW74. https://ecoevorxiv.org/repository/view/9694/ 

Editing and Music:

Intro/outro – Treehouse by Ed Nelson

Species Bi-week theme – Michael Timothy

Other Music – The Passion HiFi, https://www.thepassionhifi.com