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Members of the Euphorbiaceae are ecologically important elements of Southeast Asian forests. Species of the pioneer tree genus Macaranga, which is also known for its association with ants, are often abundant in disturbed areas. Phylogenetic studies suggested a recent radiation of section Pachystemon which comprises the majority of obligate myrmecophytes within Macaranga. In the present study, we analyzed the genetic structure of three closely related species of this section (M. constricta, M. griffithiana, and M. motleyana) with the aim of resolving their controversial taxonomy and historical biogeography. Chloroplast DNA haplotypes proved to be species-specific and showed a strong phylogeographic pattern. Nuclear microsatellite data supported the taxonomic distinctness of M. griffithiana and M. motleyana, but gave ambiguous results for M. constricta. Genetic differentiation was stronger each within M. griffithiana and M. motleyana than between M. constricta and M. griffithiana, highlighting problems of defining species boundaries. We found no indication for introgression or hybridization events. The high intraspecific morphological variation of the Bornean endemic M. motleyana was partly reflected by similar patterns of genetic variation. The pronounced genetic structure indicates a comparatively long diversification for this species. In contrast, the weak genetic differentiation within M. griffithiana, as well as the widespread distribution of its most common chloroplast haplotype from peninsular Malaysia up to Indochina, indicates a recent expansion in this area. Despite their morphological similarity and close relatedness, all species possess their own specific ant-partners with a corresponding distribution pattern.

A population genetic analysis based on eight genomic SSR markers and three EST-SSR (expressed sequence tags) markers developed in peach (Prunus persica (L.) Batsch) and Japanese plum (Prunus salicina Lindl.) was carried out in 12 wild populations of cherry plum (Prunus divaricata Ledeb.) sampled along the Iranian coast of the Caspian Sea. A total of 184 alleles (3–31 per locus) were detected with a mean value of 16.7 alleles per locus. None of the loci or populations showed deviation from Hardy–Weinberg equilibrium, and all markers proved to be unlinked. The mean values for the observed and the expected heterozygosity were 0.66 and 0.73, respectively. There was very little genetic differentiation among populations, as was indicated by low overall values of Wright’s FST (0.03) and Nei’s GST (0.08). An analysis of molecular variance (AMOVA) showed that 96.8% of the total variance was attributable to differences between individuals within populations. Genetic and geographic distances were nevertheless positively correlated, as evidenced by a Mantel test. The high level of genetic diversity and the apparent lack of genetic structure in wild P. divaricata may be attributed to frequent long distance gene flow through frugivorous birds and possibly humans, as has been documented for other Prunus species.

The viperine snake (Natrix maura) is an important agent of decline of the threatened midwife toad (Alytes muletensis) of Mallorca. However, there is a paucity of biological data to support the notion that the viperine snake is an introduced species to the island. Here we compare mitochondrial cytochrome b gene sequences and genomic ISSR-PCR fingerprints from Mallorcan and mainland European viperine snakes. Identical or nearly identical haplotypes and very similar ISSR-PCR profiles provide strong evidence that N. maura arrived only recently to Mallorca. There is no indication of a recent natural colonization of the island by transmarine dispersal. The data therefore support historical information that N. maura was introduced to Mallorca by human agency comparatively recently, and that management measures to reduce the impact of the snake on toad populations are justified.

We present morphometric data for the pink-footed shearwater (Puffinus creatopus) from both Chilean breeding colonies on Isla Mocha and Juan Fernandez: weight, total length, wing length, tail length, head length, three bill and three tarsus size measurements and length of middle toe. Significant differences were found for most measurements between males and females as well as between birds from the two different breeding localities. In general, males were bigger than females, and birds from Juan Fernandez were bigger than those from Isla Mocha. Geographic differences most likely reflect some kind of ecomorphological adaptation. Some variables, especially the total length of head, seem to be useful for sex determination in the field.

Macaranga (Euphorbiaceae) has received much ecological and evolutionary research attention as a genus that includes some of the most conspicuous pioneer trees of Southeast Asian tropical rainforests and because of its manifold associations with ants, including about 30 species that are obligate ant-plants (myrmecophytes). We used sequence data from three chloroplast DNA loci (ccmp5, ccmp6, atpB-rbcL) to assess phylogeographical patterns in species of Macaranga, section Pruinosae, sampled from various regions of Borneo and the Malay Peninsula. Forty-nine chloroplast DNA haplotypes (HT) were identified among 768 specimens from five species, Macaranga gigantea (N = 329; 23 HT), Macaranga pearsonii (N = 347; 21 HT), Macaranga puberula (N = 24; 4 HT), Macaranga hosei (N = 48; 6 HT), and Macaranga pruinosa (N = 20; 5 HT). Forty-one haplotypes were species-specific, whereas eight haplotypes were shared by two, three, or four species and occupied internal positions in a parsimony network. Population genetic parameters based on haplotype frequencies proved to be in a similar range in the non-myrmecophytic M. gigantea and in the ant-associated M. pearsonii, which have overlapping distributions in northern and eastern Borneo. A comparison of GST and NST values revealed a strong phylogeographic structure in both species, whereas colonization pathways suggested by the network topology were different. Both species exhibited similar levels of haplotypic diversity and moderate to high levels of population differentiation. There were no obvious indications for an influence of the symbiotic ant partners on the population structure of their host plants.