Our letter (Clever crows or unbalanced birds?) on the Taylor et al. paper claiming to have shown causal reasoning in crows has been published in PNAS, along with the author's reply.
You can read our letter here and the reply here.
particular scientific journey started on Twitter, where Mark
Haselgrove, Anthony McGregor and I discussed the paper. I then blogged about it, which lead to us firing off a brief, 500-word commentary to PNAS.
Interestingly, another commentary on the paper has also since been published.
Both commentaries make the point that more empirical work, with appropriate controls, is needed before it can be concluded that crows engage in causal reasoning.