Copyright © 2015 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

This manuscript version is made available after the end of the 12 month embargo period under the CC-BY-NC-ND 4.0 license
Except where otherwise noted, this item's license is described as Copyright © 2015 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved. This manuscript version is made available after the end of the 12 month embargo period under the CC-BY-NC-ND 4.0 license