Change search
ReferencesLink to record
Permanent link

Direct link
Heterospecific courtships, Allee-effects and niche separation between Leptidea sinapis and Leptidea reali
Stockholm University, Faculty of Science, Department of Zoology.
Stockholm University, Faculty of Science, Department of Zoology.ORCID iD: 0000-0003-4719-487X
Stockholm University, Faculty of Science, Department of Zoology.
(English)Manuscript (preprint) (Other (popular science, discussion, etc.))
Abstract [en]

Increasing attention is given to coevolutionary studies and to the role of ecology in local adaptation. The coevolutionary process can act in parallel throughout the distribution of species that interact in similar ecologies, whereas species interacting in varied ecological conditions might coevolve in different directions in different local populations. The butterflies Leptidea sinapis and L. reali have partitioned their niches differently in different parts of their sympatric distribution, with one species being a local habitat generalist in several different regions, and a local specialist in other areas where the sister species has adopted the habitat generalist role. Niche separation is likely independent of resource competition in this phytophagous system, and we study the potential for heterospecific sexual interference competition to redefine the suitability of a habitat and select for niche separation. We used the average female mating success in large outdoor cage experiments that varied both the absolute and relative density of the two species to estimate potential fitness costs of being in local minority. The mating success was unaffected by absolute density (conspecifics/m2) but strongly affected by the proportion of con- and heterospecifics in each cage. The proportion of mated females was ten times higher when a conspecific couple spent the day alone in the cage compared to when the single couple shared the cage with five heterospecific pairs. Being in the minority thus resulted in strong sexual interference from the locally more common competitor. We propose that these Allee effects select for habitat specialisation in the locally rare species as individuals leaving the core population likely suffer decreased fitness from spending time in heterospecific courtship. Hence, habitat suitability might depend less on local resource availability and more on the presence or absence of a local sexual competitor in this system.

Keyword [en]
Lepidoptera: Pieridae; sexual interference; male harassment; geographic mosaic; coevolution; mating success; source-sink; local adaptation; character displacement
URN: urn:nbn:se:su:diva-30792OAI: diva2:274094
Available from: 2009-10-27 Created: 2009-10-27 Last updated: 2014-10-13
In thesis
1. The evolutionary ecology of niche separation: Studies on the sympatric butterflies Leptidea sinapis and Leptidea reali
Open this publication in new window or tab >>The evolutionary ecology of niche separation: Studies on the sympatric butterflies Leptidea sinapis and Leptidea reali
2009 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Studies of ecology and evolution have become largely integrated, and increasing attention is paid to the role of ecology for speciation and post speciation divergence. In this thesis I have applied an in-depth approach studying the ecology of a butterfly species pair; the morphologically virtually identical sister-species, the Wood white (Leptidea sinapis) and Reál’s wood white (Leptidea reali). PAPER I showed a quite deep between-species division in sequence data from mitochondrial DNA. The reuniting in secondary contact zones might in contrast be quite recent, as males of L. sinapis and L. reali cannot distinguish between con- and heterospecific females (PAPER II) and since the between-species niche separation is incomplete (PAPER III, IV, V). Furthermore, the two species have partitioned their niches in different directions in different European regions as the two species shift habitat generalist and specialist roles throughout their joint distribution (PAPER III). However, the local niche partitioning has resulted in species-specific adaptations in terms of propensity to enter diapause (PAPER III, V, VI), host plant acceptance (PAPER V), and in ability to use host plant as cue for the decision to enter diapause or direct development (PAPER VI). The habitat separation is decoupled from host plant preference, at least in south central Sweden (PAPER IV), which implies that selection for niche partitioning has acted on habitat preferences directly and not via divergent selection on host plant preference. Finally, there is a high cost of appearing at a site where the other species is in the majority as much time (PAPER VII) and energy (PAPER II) are devoted to court heterospecific females or being courted by heterospecific males (PAPER VII). Hence, selection likely favours habitat specialisation in the rarest species in each region, and the direction of niche separation might simply be decided by which species that reached an area first. The species that first colonises an area would then most likely become a generalist filling up all suitable habitats, whereas the second invader might be forced to specialise, as the cost of being rare is too large everywhere but in the core population. This thesis highlights the role of ecology, and especially of local processes, for post-speciation selection and character displacement.


Place, publisher, year, edition, pages
Stockholm: Department of Zoology, Stockholm University, 2009. 44 p.
Lepidoptera, ecological character displacement, reproductive isolation, species discrimination, habitat, host plant, life history, sexual selection, female choice
National Category
Biological Sciences
Research subject
Animal Ecology
urn:nbn:se:su:diva-30822 (URN)978-91-7155-964-7 (ISBN)
Public defence
2009-11-27, Magnélisalen, Kemiska övningslaboratoriet, Svante Arrhenius väg 16 B, Stockholm, 10:00 (English)
At the time of the doctoral defense, the folowing papers were unpublished and had a status as follows: Paper 1:Manuscript. Paper 6:Manuscript. Paper 7:ManuscriptAvailable from: 2009-11-05 Created: 2009-10-27 Last updated: 2014-10-13Bibliographically approved

Open Access in DiVA

No full text

Other links

Link to doctoral dissertation

Search in DiVA

By author/editor
Friberg, MagneWiklund, ChristerLeimar, Olof
By organisation
Department of Zoology

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 149 hits
ReferencesLink to record
Permanent link

Direct link