Summary: Journal of Theoretical Biology 244 (2007) 714≠721
Autumn colours and the nutrient retranslocation hypothesis:
A theoretical assessment
St. John's College, Oxford University, St Giles, OX1 3JP Oxford, UK
Department of Zoology, Oxford University, South Parks Road, OX1 3PS Oxford, UK
Received 21 June 2006; received in revised form 14 September 2006; accepted 14 September 2006
Available online 22 September 2006
The adaptive value of the bright colours of leaves in autumn is still debated. It is possible that autumn colours are an adaptation to
protect the tree against photoinibition and photooxidation, which allows a more efficient recovery of nutrients. It has been proposed that
the preference of aphids for trees that retranslocate nitrogen more efficiently can explain the high diversity of aphids on tree species with
bright autumn colours. This scenario however does not take into account the impact of insects on the fitness of the trees and has not been
analysed theoretically. Its assumptions and predictions, therefore, remain uncertain. I show with a model of insect≠tree interaction that
the system can actually evolve under particular conditions. I discuss the differences with the coevolution theory of autumn colours,
available evidence and possible tests.
r 2006 Elsevier Ltd. All rights reserved.
Keywords: Nutrient retranslocation; Autumn colours; Coevolution; Signalling