Implications For Historical Biogeography Research Articles

Pleistocene fossil leaflets of Albizia kalkora (Roxb.) Prain (Leguminosae subfamily Mimosoideae) from central Honshu, Japan, and its implications for historical biogeography

Pleistocene fossil leaflets of Albizia kalkora (Roxb.) Prain (Leguminosae subfamily Mimosoideae) from central Honshu, Japan, and its implications for historical biogeography

Cryptic patterns of diversification of a widespread Amazonian Woodcreeper species complex (Aves: Dendrocolaptidae) inferred from multilocus phylogenetic analysis: Implications for historical biogeography and taxonomy

Inferring evolutionary relationships between recently diverged taxa is still challenging, especially taking into account the likely occurrence of incomplete lineage sorting and/or introgression. The Xiphorhynchus pardalotus/ocellatus species complex includes between two to three polytypic species and eight to nine subspecies distributed throughout most of lowland Amazonia and the foothills of the eastern Andes. To understand its historical diversification and address the main unsettled issues of phylogenetic relationships and taxonomy, we apply several approaches using data from two mitochondrial (Cyt b and ND2) and three nuclear genes (β-fibint7, CPZint3 and CRYAAint1) for all described species and most subspecies of this complex. We compared single gene trees with a multilocus concatenated tree and Bayesian species tree inferred under a coalescent framework (*BEAST). Our results showed a general pattern of incongruence among gene trees and multilocus trees. Despite of this, the coalescent-based species tree analysis supports the sister-taxa relationship of X. ocellatus and X. chunchotambo, while X. pardalotus comes out as the basal taxon. With exception of the last, our results revealed within both X. ocellatus and X. chunchotambo high levels of genetic differentiation (p-distances 0.5–5.5%) with well-supported lineages. Our phylogenetic analyses showed several incongruences with current subspecies taxonomy, revealing that X. o. ocellatus is paraphyletic relative to X. o. perplexus, and the currently recognized subspecies X. c. napensis corresponds to two distinct evolutionary lineages, which are not supported as sister-lineages. In addition, the deep level of genetic divergence between X. o. beauperthuysii and the extant subspecies of X. ocellatus is more consistent with species-level differences found in this complex. Divergence time estimates were consistent with a historical scenario of intense population subdivision and speciation during the Early-mid Pleistocene. The spatial pattern and timing of diversification overlap broadly with that reported for other Amazonian vertebrate lineages.

Altingioxylon hainanensis sp. nov.: earliest fossil wood record of the family Altingiaceae in Eastern Asia and its implications for historical biogeography

A new species, Altingioxylon hainanensis, is described from the Eocene Changchang Formation of the Changchang Basin on Hainan Island, South China. It is the first record of a fossil wood assigned to Altingiaceae found in China, and the most ancient evidence of wood for this family in eastern Asia. The new species is similar to A. rhodoleioides, known since the Miocene in India and Java Island, and to Altingiahisauchii from the Miocene to Pliocene of Japan. The close resemblance between these species and Liquidambar sp., known from the Middle Miocene of western North America, provides additional evidence for the migration of their ancestors from Asia to North America across the Bering land bridge during the Miocene. Distinctions in ray sizes between the eastern Asian specimens and their contemporaries from Europe to Kazakhstan is suggested as a result of the divergence between the large eastern Asian clade and the North American–west Asian clade within Altingiaceae during the Eocene–Oligocene. The presence of crystals in ray cells may be considered an ancestral condition that persists in the eastern Asian lineages up to the extant Altingia and Semiliquidambar, but which was lost in other Altingiaceae in the course of evolution.

Molecular phylogeny and historical biogeography of the bee genus Colletes Latreille, 1802 (Hymenoptera: Apiformes: Colletidae), based on mitochondrial COI and nuclear 28S sequence data

AbstractA phylogenetic analysis of the intrageneric relationships within the bee genus Colletes using a combined data set of the mitochondrial cytochrome oxidase 1 (COI) and 28S sequences is presented and its implications for historical biogeography are investigated. We analyzed 91 out of 469 described Colletes species (19.4%) from the entire range of distribution and 25 outgroup taxa representing all colletid subfamilies closely related to Colletinae. Eight different combinations of alignment parameters were used for the 28S data, and our combined data set comprised between 1801 and 1845 aligned nucleotides with COI contributing 339 informative bases and 28S between 318 and 360 informative sites. Our results corroborate the monophyly of about half of the Old World subgenera and show the need for a taxonomic re-delimitation of other groups currently accepted. The phylogenetic results confirm the South American origin of Colletes and multiple faunal exchange events between North America and Eurasia. The last continent colonized was Africa south of the Sahara, which experienced at least two independent invasions.

Classification tree and minimum‐volume ellipsoid analyses of the distribution of ponderosa pine in the western USA

AbstractAim Ponderosa pine (Pinus ponderosa Douglas ex Lawson & C. Lawson) is an economically and ecologically important conifer that has a wide geographic range in the western USA, but is mostly absent from the geographic centre of its distribution – the Great Basin and adjoining mountain ranges. Much of its modern range was achieved by migration of geographically distinct Sierra Nevada (P. ponderosa var. ponderosa) and Rocky Mountain (P. ponderosa var. scopulorum) varieties in the last 10,000 years. Previous research has confirmed genetic differences between the two varieties, and measurable genetic exchange occurs where their ranges now overlap in western Montana. A variety of approaches in bioclimatic modelling is required to explore the ecological differences between these varieties and their implications for historical biogeography and impending changes in western landscapes.Location Western USA.Methods We used a classification tree analysis and a minimum‐volume ellipsoid as models to explain the broad patterns of distribution of ponderosa pine in modern environments using climatic and edaphic variables. Most biogeographical modelling assumes that the target group represents a single, ecologically uniform taxonomic population. Classification tree analysis does not require this assumption because it allows the creation of pathways that predict multiple positive and negative outcomes. Thus, classification tree analysis can be used to test the ecological uniformity of the species. In addition, a multidimensional ellipsoid was constructed to describe the niche of each variety of ponderosa pine, and distances from the niche were calculated and mapped on a 4‐km grid for each ecological variable.Results The resulting classification tree identified three dominant pathways predicting ponderosa pine presence. Two of these three pathways correspond roughly to the distribution of var. ponderosa, and the third pathway generally corresponds to the distribution of var. scopulorum. The classification tree and minimum‐volume ellipsoid model show that both varieties have very similar temperature limitations, although var. ponderosa is more limited by the temperature extremes of the continental interior. The precipitation limitations of the two varieties are seasonally different, with var. ponderosa requiring significant winter moisture and var. scopulorum requiring significant summer moisture. Great Basin mountain ranges are too cold at higher elevations to support either variety of ponderosa pine, and at lower elevations are too dry in summer for var. scopulorum and too dry in winter for var. ponderosa.Main conclusions The classification tree analysis indicates that var. ponderosa is ecologically as well as genetically distinct from var. scopulorum. Ecological differences may maintain genetic separation in spite of a limited zone of introgression between the two varieties in western Montana. Two hypotheses about past and future movements of ponderosa pine emerge from our analyses. The first hypothesis is that, during the last glacial period, colder and/or drier summers truncated most of the range of var. scopulorum in the central Rockies, but had less dramatic effects on the more maritime and winter‐wet distribution of var. ponderosa. The second hypothesis is that, all other factors held constant, increasing summer temperatures in the future should produce changes in the distribution of var. scopulorum that are likely to involve range expansions in the central Rockies with the warming of mountain ranges currently too cold but sufficiently wet in summer for var. scopulorum. Finally, our results underscore the growing need to focus on genotypes in biogeographical modelling and ecological forecasting.