DOI: 10.5061/dryad.5hqbzkh31
title: Phenological responses to climate warming in temperate moths and butterflies: species traits predict future changes in voltinism

description: Changes in the number of generations per year (voltinism) have been among
 the most common phenological responses to climate warming in insects
 inhabiting seasonal environments. Nevertheless, numerous species have
 maintained univoltine (one generation per year) phenology with increasing
 temperatures, indicating the involvement of phylogenetic, ecological or
 some other constraints on phenological change. I examined geographic
 variation in voltinism in moths and butterflies of Northern Europe to
 identify species traits that might predispose species to
 univoltine/multivoltine phenology. I focused on species with a wide
 latitudinal distribution range (15 degrees as a minimum) which makes it
 unlikely that constraints imposed by season length could preclude
 multivoltinism across their distribution. Almost half of the 731 moth and
 butterfly species considered appear to have a single generation throughout
 their entire European range. A univoltine life-cycle across a wide
 latitudinal gradient suggests the presence of some constraint that makes
 additional generations either impossible or at least strongly
 disadvantageous, which will unlikely change with future climate warming.
 The scattered distribution of univoltine and multivoltine species across
 the lepidopteran phylogeny indicates that phylogenetic constraints are not
 strongly limiting changes in voltinism, and the trait is open to
 ecologically-driven adaptive evolution. My data show that species with one
 generation per year are generally larger than multivoltine species, but
 size forms no absolute constraint to having multiple generations per year.
 Obligately univoltine species dominate among egg and adult overwinterers
 (life-histories typical of so-called spring-feeders), whereas species with
 capacity for multiple generations prevail among pupal overwinterers.
 Multivoltinism is also infrequent among species feeding on grasses,
 particularly in endophagous grass-feeders. Larval diet breadth has no
 discernible effect on voltinism. Given the diverse ecological consequences
 of voltinism and its changes, accounting for the species’ capacity for
 multivoltinism may be a key to address future challenges in biodiversity
 conservation and pest management.
description: The data set used in this study is mostly literature-derived.
 Details regarding the collection, sources and processing of the data are
 described in full in the paper.
description: <strong>Explanations for the data set</strong>.
 <strong>size </strong>= adult wing span,
 <strong>overwintering stage</strong>: E = egg, L = larva, P =
 pupa, A = adult, AP = adult within pupal case (classified as adult
 overwinterers in the analysis); <strong>host type</strong>: W
 = woody plants (species feeding exclusively on coniferous trees are
 indicated by W(c)), F = forbs, G = grasses (endophagous grass-feeders are
 indicated by G(i)), WH = woody + herbaceous plants, L = lichens;
 <strong>larval diet breadth</strong>: M = monophagous, O =
 oligophagous, P = polyphagous; voltinism: U = univoltine, M =
 multivoltine.