Associative learning accounts for recursive-structure generation in crows.

Recursive sequence generation (i.e., the ability to transfer recursive patterns to novel items) was recently reported in crows (Liao et al., 2022, Science Advances, 8[44], eabq3356). Here, we argue that although the reported data are certainly compatible with the recursion hypothesis, they can also be explained by other, much simpler mechanisms of associative learning.