Genetic assimilation of behaviour does not eliminate learning and innovation

Abstract

Innovation is a key component of most definitions of culture and intelligence. Additionally, innovations may affect a species' ecology and evolution. Nonetheless, conceptual and empirical work on innovation has only recently begun. In particular, largely because the existing operational definition (first occurrence in a population) requires long-term studies of populations, there has been no systematic study of innovation in wild animals. To facilitate such study, we have produced a new definition of innovation: Innovation is the process that generates in an individual a novel learned behavior that is not simply a consequence of social learning or environmental induction. Using this definition, we propose a new operational approach for distinguishing innovations in the field. The operational criteria employ information from the following sources: (1) the behavior's geographic and local prevalence and individual frequency; (2) properties of the behavior, such as the social role of the behavior, the context in which the behavior is exhibited, and its similarity to other behaviors; (3) changes in the occurrence of the behavior over time; and (4) knowledge of spontaneous or experimentally induced behavior in captivity. These criteria do not require long-term studies at a single site, but information from multiple populations of a species will generally be needed. These criteria are systematized into a dichotomous key that can be used to assess whether a behavior observed in the field is likely to be an innovation.

A genome‐wide investigation of adaptive signatures in protein‐coding genes related to tool behaviour in New Caledonian and Hawaiian crows

“…At present, it is unclear whether selection for specialized craniofacial features preceded (e.g. to enable woodpecker‐like chiselling of deadwood; for Rutz & St Clair, 2012), and/or followed (Hunt & Gray, 2007; Matsui et al, 2016), the emergence of tool behaviour (Troscianko et al, 2012). In any case, while morphological change seems a necessary component for the early evolution of habitual dexterous tool behaviour, more subtle changes affecting ontogenetic programmes and cognitive capacities may also occur, but remained undetected in our present analyses.…”

The life-history basis of behavioural innovations

“…According to the delayed benefits hypothesis, a long developmental period is necessary to acquire the behavioural skills needed to survive as adults [38]. New Caledonian crows, a species with an unusual ability for innovative tool use, have one of the longest known periods of extended parental provisioning in birds, with some parents regularly feeding juveniles for up to 10 months post-fledging [44]. The delayed benefits hypothesis is compatible with the cognitive buffer because it suggests some benefit of enhanced innovativeness during adulthood.…”

Cognitive insights from tool use in nonhuman animals.

“…An obvious adaptation for tool use in New Caledonian crows is a genetic predisposition to develop basic tool skills (Hunt, Lambert, & Gray, 2007, Kenward, Rutz, Weir, & Kacelnik, 2006Kenward, Weir, Rutz, & Kacelnik, 2005). Such a disposition, however, does not exclude learning and innovation in the development and transmission of their tool behavior (Hunt, Abdelkrim, et al, 2007;Hunt & Gray, 2007a). Indeed, their impressive foraging techniques in the wild suggest that they have special cognitive abilities for developing innovative foraging solutions.…”

“…Hunt et al (2013) proposed that the differences between birds and primates might be due by different processes and mechanisms of transmission. Once tool use in New Caledonian crows appeared, strong selection probably drove their suggested adaptive complex for this behavior (Hunt & Gray, 2007a). In fact, the widespread occurrence of basic tool skills in New Caledonian crows and woodpecker finches has a strong genetic basis (Tebbich et al, 2001;Kenward et al, 2005).…”