Search results for " biogeography"
showing 10 items of 64 documents
A new genus for the eastern dwarf galagos (Primates: Galagidae).
2017
13 pages; International audience; The family Galagidae (African galagos or bushbabies) comprises five genera: EuoticusGray, 1872; GalagoGeoffroy Saint-Hilaire, 1796; GalagoidesSmith, 1833; OtolemurCoquerel, 1859; and SciurocheirusGray, 1872, none of which is regarded as monotypic, but some (Euoticus and Otolemur) certainly qualify as oligotypic. We argue for the recognition of a sixth genus, if the taxonomy is to reflect galagid evolution accurately. Genetic evidence has consistently demonstrated that the taxa currently referred to the genus Galagoides are not monophyletic but form two clades (a western and an eastern clade) that do not share an exclusive common ancestor; we review 20 years…
Staying cool: preadaptation to temperate climates required for colonising tropical alpine-like environments.
2018
Plant species tend to retain their ancestral ecology, responding to temporal, geographic and climatic changes by tracking suitable habitats rather than adapting to novel conditions. Nevertheless, transitions into different environments or biomes still seem to be common. Especially intriguing are the tropical alpine-like areas found on only the highest mountainous regions surrounded by tropical environments. Tropical mountains are hotspots of biodiversity, often with striking degrees of endemism at higher elevations. On these mountains, steep environmental gradients and high habitat heterogeneity within small spaces coincide with astounding species diversity of great conservation value. The …
Parallel diversifications of Cremastosperma and mosannona (annonaceae), tropical rainforest trees tracking neogene upheaval of South America
2018
Much of the immense present day biological diversity of Neotropical rainforests originated from the Miocene onwards, a period of geological and ecological upheaval in South America. We assess the impact of the Andean orogeny, drainage of Lake Pebas and closure of the Panama isthmus on two clades of tropical trees ( Cremastosperma , ca 31 spp.; and Mosannona , ca 14 spp.; both Annonaceae). Phylogenetic inference revealed similar patterns of geographically restricted clades and molecular dating showed diversifications in the different areas occurred in parallel, with timing consistent with Andean vicariance and Central American geodispersal. Ecological niche modelling approaches show phyloge…
Frequent colonization and little in situ speciation in Senecio in the tropical alpine-like islands of eastern Africa.
2016
Premise of the study Floras of continental habitat islands, like those of islands, originate mostly through colonization, which can be followed by in situ speciation. We here address the question of the relative importance of colonization and in situ diversification in the high-altitude areas of the eastern African high mountains, the tropical Afroalpine Region, using the most species-rich genus in the region, Senecio, as an example. Methods We expanded earlier Senecioneae phylogenies by adding more tropical African species and analyzed our phylogenetic tree biogeographically. Key results Senecio contains at least five clades with tropical African species, all of them containing tropical af…
On the origin of the recent herpetofauna of Sicily: Comparative phylogeography using homologous mitochondrial and nuclear genes
2016
Abstract In contrast to oceanic, continental islands are expected to show less diversification and endemism and thus phylogeographic signatures of multiple colonization events from adjacent continents due to episodic connections by sea level changes. In order to test this situation for the herpetofauna of Sicily, we here focus on three amphibian and four reptile species-groups and investigate their phylogeographic relationships across the Sicily and Messina straits, where Plio-Pleistocene marine transgressions shortened the distances between (or connected) Sicily, North Africa and/or the Italian (Apennine) Peninsula. Using a multi-species, multi-marker phylogeographic approach (mitochondria…
Absence inattendue d'espèces endémiques insulaires: Dissémination sur de longues distances chez des espèces de Siphonaria sub-antarctique de haute la…
2018
International audience; Aim: We assess biogeographical patterns, population structure and the range of species in the pulmonate genus Siphonaria across the sub‐Antarctic. We hypothesized that locally endemic cryptic species will be found across the distribution of these direct‐developing limpets in the sub‐Antarctic.Location: The sub‐Antarctic coasts of the Southern Ocean including South America, the Falkland/Malvinas, South Georgia, Kerguelen and Macquarie Islands.Methods: Multi‐locus phylogenetic reconstructions, mtDNA time‐calibrated divergence time estimations and population‐based analyses of Siphonaria populations were used at the scale of the Southern Ocean.Results: We resolve two wid…
Does the genetic diversity among pubescent white oaks in southern Italy, Sicily and Sardinia islands support the current taxonomic classification?
2020
AbstractMolecular diversity analysis of deciduous pubescent oaks was conducted for populations from Calabria, Sicily and Sardinia. The aims of this study were twofold. First, to provide data on the genetic diversity of pubescent oaks from an understudied area which currently exhibits one of the highest concentrations of pubescent oak species in Europe. Second, to verify if these groups of oaks are genetically distinct and if their identification is in accordance with the current taxonomic classification. Molecular analyses of leaf material of 480 trees from seventeen populations belonging to putatively different pubescent oak species (Quercus amplifolia,Q. congesta,Q. dalechampii,Q. ichnusa…
sPlotOpen – An environmentally balanced, open‐access, global dataset of vegetation plots
2021
Datos disponibles en https://github.com/fmsabatini/sPlotOpen_Code
Molecular and morphological data suggest weak phylogeographic structure in the fairy shrimp Streptocephalus torvicornis (Branchiopoda, Anostraca)
2017
Inland aquatic organisms almost ubiquitously display a pattern of marked provincialism characterized by substantial population differentiation and genealogical discontinuities. This is the result of strong priority effects and local adaptation following dispersal and colonization of new habitats. We present a case that defies this biogeographic paradigm. We have investigated the phylogeography of the fairy shrimp Streptocephalus torvicornis across its circum-Mediterranean and Eurasian distribution. Based on three independent datasets, namely sequence variation at 12S and 16S rRNA, cyst morphology and male second antenna characters, we discern a pattern of extensive genetic and morphological…
Mediterranean sponges from shallow subtidal rocky reefs: Cystoseira canopy vs barren grounds
2018
Abstract Porifera richness was investigated in Cystoseira canopies vs barren grounds considering different substrates at 6 areas in the Central-Western Mediterranean Sea. In total 31 sponge taxa were recorded at 2–7 m depth and the sponge community structure and composition were characterized by a notably low richness with 25 taxa in the Cystoseira forest and 15 in the barren area. As for the sponge habitus, the massive sponges were dominant in both facies, whereas encrusting, and cavity dwelling sponges were found in higher numbers in the Cystoseira forest. Results revealed that rocky substrata seem to play a key role in driving the sponge community composition and diversity in both facies…