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Vol. 44 No. 1, 2005
Calling Song Structure and Geographic Variation in Cicada orni Linnaeus (Hemiptera: Cicadidae)
Gabriela Pinto-Juma1, Paula C. Simões1,2, Sofia G. Seabra1, and José A. Quartau1,2,*
1Centro de Biologia Ambiental C2-3°Piso, Faculdade de Ciências de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
2Departamento de Biologia Animal, C2-3°Piso, Faculdade de Ciências de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
Gabriela Pinto-Juma, Paula C. Simões, Sofia G. Seabra, and José A. Quartau (2005) An analysis of the structure of the calling song of Cicada orni
Linnaeus, 1758 over a selected part of its distribution range in the
Mediterranean area was carried out in order to better understand the
pattern of its geographic variation and population history. Calling
songs of males from several localities in western and southeastern
Europe were recorded from 1995 to 2003, and were analysed in time and
frequency domains. The calling songs analyzed constituted a relatively
homogeneous group. However, there was some tendency of songs from
southeastern Europe (Greece) to group apart from those of western
Europe (Iberian Peninsula and France). The inter-echeme interval
duration was the variable that contributed most to this separation, but
males from Greece showed significant differences in almost every
acoustic variable in relation to the remaining studied regions. This
acoustic differentiation is in agreement with introductory genetic
results still under investigation. Echeme duration proved to be quite
constant across the geographic range of this cicada and, as such, is
probably one of the most important parameters encoding species-specific
information for species recognition. Conversely, the inter-echeme
interval was quite variable, and so it is expected that this variable
is not an important parameter for species recognition and isolation in C. orni.
The observed distinctiveness of the populations of the Aegean area may
be the result of repeated cycles of isolation in southern refugia
through the mountain ranges of the Balkans during the ice ages.
Furthermore, it is hypothesized that the Aegean area and West Asia
Minor might constitute the main area of origin of C. orni.
Key words: Cicada orni, Calling song, Acoustic signals, Acoustic divergence, Geographic variation.
*Correspondence: Tel: 351-21-7500000. Fax: 351-21-7500028. E-mail: jaquartau@fc.ul.pt
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