Genetic divergence and phylogeography in the genus Nyctalus (Mammalia, Chiroptera): implications for population history of the insular bat Nyctalus azoreum (original) (raw)
Related papers
2004
The Azorean bat Nyctalus azoreum is the only endemic mammal native to the remote archipelago of the Azores. It evolved from a continental ancestor related to the Leisler's bat Nyctalus leisleri and is considered threatened because of its restricted and highly fragmented distribution. We studied the genetic variability in 159 individuals from 14 colonies sampled throughout the archipelago. Sequences of the D-loop region revealed moderate but highly structured genetic variability. Half of the 15 distinct haplotypes were restricted to a single island, but the most common was found throughout the archipelago, suggesting a single colonization event followed by limited interisland female gene flow. All N. azoreum haplotypes were closely related and formed a star-like structure typical of expanded populations. The inferred age of demographic expansions was consistent with the arrival of founder animals during the Holocene, well before the first humans inhabited the Azores. Comparisons with a population of N. leisleri from continental Portugal confirmed not only that all N. azoreum lineages were unique to the archipelago, but also that the current levels of genetic diversity were surprisingly high for an insular species. Our data imply that the Azorean bat has a high conservation value. We argue that geographical patterns of genetic structuring indicate the existence of two management units.
2010
a bstract. The azorean bat (Nyctalus azoreum), the only endemic mammal of the azores archipelago (Portugal), diverged recently from its mainland relative, the leisler's bat (N. leisleri). although the two species are phenotypically very different, mtDNa studies detected very low genetic divergence between them, which could question the validity of the species status of N. azoreum. in order to assess the genetic variability in each species and check for present levels of gene flow between the two taxa, eight microsatellite loci were genotyped and analysed. The results indicated lower genetic diversity in the insular species. Many unshared alleles were found between the two species and no evidence of migrants, which provides strong support against any contemporary gene flow between them. The species status of the azorean bat is discussed in the light of the cohesion species concept, and we conclude that it is an isolated species with a high conservation value.
Intraspecific evolution of Canary Island Plecotine bats, based on mtDNA sequences
Heredity, 2003
Island differentiation and relationships with congenerics were investigated in the endemic Canary Island bat Plecotus teneriffae, based on B1 kb of mtDNA from the 16S rRNA and cytochrome b genes. P. teneriffae had closer affinities with P. austriacus than with P. auritus. Levels of differentiation between Canary Islands were quite high relative to Pipistrelle-like bats, consistent with philopatric behaviour in the Plecotus genus. Cladogenesis within P. teneriffae appears to have occurred after the emergence of the islands of El Hierro and La Palma during the Pleistocene. An intraspecific network shows that haplotypes from the younger islands of La Palma and El Hierro are connected to the Tenerife haplotype by a similarly large number of mutational steps. This suggests that they were both colonised at a similar time from the much older island of Tenerife. The other Plecotine bat species, Barbastellus barbastellus shows close affinities with B. barbastellus from mainland Spain, with levels of mtDNA divergence being comparable with intraspecific variation within other mammal species.
Taxonomy, status and distribution of the Azorean bat (Nyctalus-azoreum).
Journal of zoology, 2003
The taxonomic status of the Azorean bat i Nvctahrs (lzO/'cum Thomas 190!) was assessed, by a principal components analysis of measurements of the external morphology of the bat. together with specimens of the closest related Nyctalus species from mainland Europe (Nvctalus leislcrit. This analysis confirms the recent suggestion, based on a similar analysis of skull morphology, That the Azorean bat represents a good species, distinguished from N. leislcri by its smaller sizeforearm lengths for N. azoreuin in range 35·7-42'0 mm (11= 14). compared with 42·0-45·R mm (11 = 8) for N. leisleri. The status and distribution of the Azorean bat was assessed by a survey conducted in the Islands in September and October 1988. We assessed the presence or absence of bats, in62 (l ' latitude x l ' longitude) plots at the west end of the island of Sao Miguel. The study area covered 6% of the total land area of the archipelago and contained representative areas of all the major island habitat types. A less intensive survey throughout lour other islands. literature review and information from other sources revealed that the bat is probably distributed throughout the entire archipelago. with the possible exception of Flores and Corvo. Bats were active both in the day and at night. At night. bats were mostly active in coastal villages where they were closely associated with street lighting. During the day. most bats were active in the inland areas near to Caldeira lakes. The maximum number of bats observed simultaneously active in thc day was six whilst at dusk swarms of up to 55 (± 5) bats were observed together. At night. bats were also active over approximately ]·5 x the area they occupied in the day. By assuming the bat is found throughout the archipelago. and that our study area was representative, we estimated the maximum population to be between 1750 (from daylight activity) and 23.650 (from nocturnal activity). This latter estimate implies a fOP Illation density throughout the archipelago of around O'I bats per hectare.
Molecular Phylogenetics and Evolution, 2004
Long-eared bats of the genus Plecotus are widespread and common over most of the western Palaearctic. Based on recent molecular evidence, they proved to represent a complex of several cryptic species, with three new species being described from Europe in 2002. Evolutionary relationships among the different lineages are still fragmentary because of the limited geographic coverage of previous studies. Here we analyze Plecotus mitochondrial DNA sequences from the entire Mediterranean region and Atlantic Islands. Phylogenetic reconstructions group these western Palaearctic Plecotus into two major clades which split at least 5 Myr ago and that are each subdivided into further subgroups. An Ôauritus groupÕ includes the traditional P. auritus species and its sister taxon P. macrobullaris ( ¼ P. alpinus) plus related specimens from the Middle East. P. auritus and P. macrobullaris have broadly overlapping distributions in Europe, although the latter is apparently more restricted to mountain ranges. The other major clade, the Ôaustriacus group,Õ includes the European species P. austriacus and at least two other related taxa from North Africa (including P. teneriffae from the Canary Islands), the Balkans and Anatolia (P. kolombatovici). The sister species of this Ôaustriacus groupÕ is P. balensis, an Ethiopian endemic. Phylogenetic reconstructions further suggest that P. austriacus reached Madeira during its relatively recent westwards expansion through Europe, while the Canary Islands were colonized by a North African ancestor. Although colonization of the two groups of Atlantic Islands by Plecotus bats followed very distinct routes, neither involved lineages from the Ôauritus group.Õ Furthermore, the Strait of Gibraltar perfectly segregates the distinct lineages, which confirms its key role as a geographic barrier. This study also stresses the biogeographical importance of the Mediterranean region, and particularly of North Africa, in understanding the evolution of the western Palaearctic biotas.
Conservation Genetics, 2008
The Azorean bat (Nyctalus azoreum) is endemic to the Azores archipelago and is listed as endangered due to its reduced and fragmented distribution range. We assessed genetic diversity at eight microsatellite loci in 280 individuals from 14 locations throughout six islands. Overall, we found that the Azorean bat populations are not genetically impoverished. Indeed, the number of alleles per locus ranged from 8 to 10 and the observed heterozygosity ranged from 0.77 in Terceira to 0.83 in Faial. The highest genetic diversity and level of private alleles was observed in S. Miguel, the largest island, and the closest to the mainland. Private alleles occurred at all islands except in Graciosa. Global and pairwise F ST among islands were all statistically significant, suggesting restricted gene flow. These results, together with those of factorial correspondence analysis, Bayesian clustering method, and individual assignment tests, corroborate the conclusions of a previous mtDNA based study, providing strong support for the existence of two major subpopulations: one includes all islands of the Central Group and the other corresponds to S. Miguel. Gene flow between them is very limited, suggesting that management plans should avoid translocations between these subpopulations.
Molecular Phylogenetics and Evolution. 2004. 31(3): 1114-1126., 2004
Long-eared bats of the genus Plecotus are widespread and common over most of the western Palaearctic. Based on recent molecular evidence, they proved to represent a complex of several cryptic species, with three new species being described from Europe in 2002. Evolutionary relationships among the different lineages are still fragmentary because of the limited geographic coverage of previous studies. Here we analyze Plecotus mitochondrial DNA sequences from the entire Mediterranean region and Atlantic Islands. Phylogenetic reconstructions group these western Palaearctic Plecotus into two major clades which split at least 5 Myr ago and that are each subdivided into further subgroups. An ‘auritus group’ includes the traditional P. auritus species and its sister taxon P. macrobullaris (=P. alpinus) plus related specimens from the Middle East. P. auritus and P. macrobullaris have broadly overlapping distributions in Europe, although the latter is apparently more restricted to mountain ra...
Acta Chiropterologica, 2018
Wagner’s mustached bat (Pteronotus personatus) is an insectivorous bat distributed throughout America from Mexico to Brazil, which inhabits a range of habitats from rain forests to dry deciduous forests. There are two currently recognized species within the P. personatus complex, for which we examined 235 cytochrome oxidase I (COI) sequences and 138 cytochrome b (Cytb) sequences in order to explore its genetic variation in Mexico as well as in Central and South America. Our results reveal considerable differences in the genetic structure inside this species complex, indicating five genetic lineages: 1) Gulf of Mexico and the Mexican Pacific coastal plain to the Isthmus of Tehuantepec, 2) Southeastern Mexico, 3) Guatemala, 4) Guyana and Suriname-COI/Guyana and Venezuela-Cytb, and 5) Guyana, Suriname, French Guiana and Brazil. In addition, we used the isolation-with-migration coalescent method to estimate divergence times. The results indicate that vicariant events occurred roughly 1,624,000–2,450,000 years ago during the Early Pleistocene, wherein Central America was the center of two separate diversification processes, one toward Mexico and the other South America. The intraspecific lineages obtained for P. personatus demonstrate the need to reevaluate the species complex limits of this taxon.
Species endemic to oceanic islands offer unique insights into the mechanisms underlying evolution and have served as model systems for decades. Often these species show phenotypic variation that is correlated with the ecosystems in which they occur and such correlations may be a product of genetic drift, natural selection, and/or environmental factors. We explore the morphologic and genetic variation within Ardops nichollsi, a species of phyllostomid bat endemic to the Lesser Antillean islands. Ardops nichollsi is an ideal taxon to investigate the tempo of evolution in Chiroptera, as it: is a recently derived genus in the family Phyllostomidae; contains intraspecific morphological variation; and has a restricted insular distribution. To evaluate patterns of evolution in A. nichollsi, we used standard morphological analyses, in addition to analyzing Amplified Fragment Length Polymorphisms, mitochondrial cytochrome-b, and paternal marker zinc finger Y-chromosomal intron DNA sequence data. Our results identified a pattern that consists of two distinct evolutionarily lineages, which correspond to northern and southern islands of the Lesser Antilles. We also describe a new subspecies from the southern island of Saint Vincent. These results indicate gene flow among northern Lesser Antillean populations during the Pleistocene, and local adaptation to individual islands in the southern Lesser Antilles. Our findings can be used to further explore speciation processes within Caribbean bats and, more broadly, within species distributed across other insular systems.