Phenetic Relationships among Populations of Podarcis Sicula and P. Melisellensis (Sauria: Lacertidae) from Islands in the Adriatic Sea

• Published in: Systematic Biology
• Main Author: Clover, Robert C.
• Format: Text
• Language: English
• Published: Oxford University Press 1979
• Subjects: Articles; Close Islands; Southern Island
• Online Access: http://sysbio.oxfordjournals.org/cgi/content/short/28/3/284; https://doi.org/10.1093/sysbio/28.3.284

Phenetic relationships among populations 0/Podarcis sicula and P. melisellensis (Sauria: Lacertidae) from islands in the Adriatic Sea. Syst. Zool. 28:284–298.— Thirtyone island populations of Podarcis sicula and P. melisellensis from Yugo slavia were examined to determine phenetic similarities based on means of 15 characters. Both cluster analysis and multidimensional scaling (MDS) revealed the following patterns of variation: 1) the two species formed distinct groups; 2) within each species, OTUs from northern and southern islands grouped separately; 3) within P. melisellensis, OTUs from small islands tended to resemble other small island OTUs from geographically close islands. These patterns appear to contradict similarities implied by previous subspecific designations based largely on color and pattern differences. Genetic drift, gene flow, and selection are evaluated as explanations for observed phenetic patterns. Drift appears to be highly unlikely as a major force determining regional, large island, and small island similarities among OTUs. Channel depths and estimates of the rate of net increase in sea level suggest that the northern islands are younger than the southern islands, supporting the idea that gene flow has been restricted among the southern islands and between the two regions for a longer time than among the northern islands. Combined with differences in selection regimes, the recency of gene flow appears to have been important in determining north–south phenetic similarities. Populations on small islands are exposed to qualitatively different selection regimes than those on large islands. The closer similarity of northern, small island OTUs to large island OTUs suggests that the northern OTUs have not responded to small island selection regimes to the same extent that southern island OTUs have.