Intelligence in Corvids and Apes: A Case of Convergent Evolution?

Abstract

Intelligence is suggested to have evolved in primates in response to complexities in the environment faced by their ancestors. Corvids, a large‐brained group of birds, have been suggested to have undergone a convergent evolution of intelligence [Emery & Clayton (2004) Science, Vol. 306, pp. 1903–1907]. Here we review evidence for the proposal from both ultimate and proximate perspectives. While we show that many of the proposed hypotheses for the evolutionary origin of great ape intelligence also apply to corvids, further study is needed to reveal the selective pressures that resulted in the evolution of intelligent behaviour in both corvids and apes. For comparative proximate analyses we emphasize the need to be explicit about the level of analysis to reveal the type of convergence that has taken place. Although there is evidence that corvids and apes solve social and physical problems with similar speed and flexibility, there is a great deal more to be learned about the representations and algorithms underpinning these computations in both groups. We discuss recent comparative work that has addressed proximate questions at this level, and suggest directions for future research.

Referential gestures in fish collaborative hunting

“…On the neurophysiological level there is recent evidence that the reward structure of fish brains is similar to that of mammals 47 . In conclusion, primates and corvids do appear to be particularly cognitive clades, demonstrated by a variety of complex cognitive processes their constituent species are apparently capable of 14,15 . However, our results emphasize the importance of a more general evolutionary view of cognition [16][17][18] , which predicts that species evolve cognitive solutions according to their ecological needs.…”

“…Recently, Pika and Bugnyar 13 provided evidence for the use of referential gestures by a non-primate in their study on wild ravens that show and offer non-food items to conspecifics apparently in the context of social bonding between pair partners. Pika and Bugnyar interpreted their results as further evidence that, in some domains, the cognitive abilities of corvids are comparable to those of primates 14,15 . Although the cognitive similarities between these two large-brained clades may well hold true with respect to their long list of shared abilities, an ecologically driven concept of cognition would predict that any single capacity may evolve as a function of ecological need [16][17][18] .…”

Social learning in New Caledonian crows

“…Like many primate species, corvids tend to be omnivorous, generalist foragers (Emery, 2006). It has been suggested, therefore, that similar socioecological pressures might have led to a convergent evolution of intelligence in corvids and apes (Emery & Clayton, 2004;Seed et al, 2009).…”

“…More recently, however, another animal group has received considerable attention in these areas of cognitive research: corvids. Corvids have demonstrated cognitive abilities that rival those of the great apes (Bird & Emery, 2009Bugnyar, 2008;Emery, 2004;Seed, Emery, & Clayton, 2009;Taylor, Hunt, Holzhaider, & Gray, 2007;Taylor, Hunt, Medina, & Gray, 2009;Taylor, Roberts, Hunt, & Gray, 2009;Tebbich, Seed, Emery, & Clayton, 2007). Like the brains of primates, corvid brains are significantly larger than would be predicted from their body size (Jerison, 1973).…”

Biological and artificial cognition: what can we learn about mechanisms by modelling physical cognition problems using artificial intelligence planning techniques?

“…In recent years, increasingly elegantly designed experiments testing a range of non-human animal species in both the wild and captivity have shown that many species are capable of behaviours of complexity that surprised investigators (see recent studies [1][2][3] for reviews). However, these experiments have also revealed that in many cases, we (animal cognition researchers) lack appropriate analytical tools to enable us to de-construct those behaviours, compare the competences within or between species, or to tentatively assign biological mechanisms.…”