15 research outputs found
The Systematic Position Of The Genus Basityto Mlikovsky, 1998 (Aves : Gruiformes : Gruidae)
Volume: 114Start Page: 964End Page: 97
Why are woody plants fleshyâfruited at low elevations? Evidence from a highâelevation oceanic island
Question: The composition of fruit types, fleshy vs dry fruits, greatly influences the functioning of plant communities. Literature documenting spatial patterns of fruit types at fine scale is abundant. However, studies at larger geographical scale remain scarce, especially on high-elevation oceanic islands that provide a great environmental heterogeneity. Here, we investigated how abiotic factors explained the proportion of fleshy-fruited species (pFF) on RĂ©union. We asked (a) which abiotic factors were most related to pFF, (b) if fleshy-fruited canopy species were more sensitive than fleshy-fruited shrubs to harsh climatic conditions and (c) what are the relationships between pFF, endemism and phylogenetic relatedness.Location: RĂ©union (3,070 m a.s.l), Mascarene archipelago, SouthWest Indian Ocean.Methods: We used a dataset of 429 vegetation plots and assigned fruit types, growth forms and geographical distribution to 213 native woody species. Phylogenetic trees were constructed for each plot. We used GLMs to measure the relationship between pFF and abiotic factors, controlling for spatial autocorrelation. We then assessed the relationship between pFF, the standardized net relatedness index and the proportion of endemic species.Results: The top model explained 78% of the variation in pFF. Elevation was by far the best predictor, with pFF decreasing from 81% at 50 m a.s.l to 0% at 3,000 m a.s.l. At low elevations, pFF was higher on the wet windward (81%) than on the leeward (70%) where phylogenetic clustering was evident. Almost half (48%) of woody plants was fleshy-fruited trees at low elevations. The proportion of fleshy-fruited trees declined sharply with elevation and was significantly related to precipitation of the driest month contrary to the proportion of fleshy-fruited shrubs that showed a hump shaped pattern along elevational gradient and no correlation with precipitation of the driest month. At high elevations, most plant assemblages were phylogenetically clustered and strongly dominated by single-island endemic dry-fruited plants. Conclusions: The striking relationship between pFF and elevation, the shift among fleshy-fruited growth forms along climatic gradients and the phylogenetic clustering of assemblages subjected to harsh climatic conditions, suggested that climatic factors were the main drivers of the distribution of fruit types on RĂ©union. To explain the absence of fleshy-fruited species at high elevations, we hypothesized that native fleshy-fruited lineages lacked the evolutionary potential to adapt and fleshy-fruited cold-adapted lineages had major difficulties reaching RĂ©union
Why are woody plants fleshyâfruited at low elevations? Evidence from a highâelevation oceanic island
A phylogeny of kingfishers reveals an Indomalayan origin and elevated rates of diversification on oceanic islands
Position of the palaeontological site Aven I des AbĂźmes de La Fage, at Noailles (CorrĂšze, France), in the European Pleistocene chronology
Two new fossil parrots (Psittaciformes) from the Lower Eocene Fur Formation of Denmark
Two new fossil psittaciform birds from the Lower Eocene âMo Clayâ (Fur Formation) of Denmark (c. 54 Ma) are described. An unnamed specimen is assigned to the extinct avian family of stem-group parrots, Pseudasturidae (genus and species incertae sedis), while a second (Mopsitta tanta gen. et sp. nov.) is the largest fossil parrot yet known. Both specimens are the first fossil records of these birds from Denmark. Although the phylogenetic position of Mopsitta is unclear (it is classified as family incertae sedis), this form is phylogenetically closer to Recent Pstittacidae than to other known Palaeogene psittaciforms and may, therefore, represent the oldest known crown-group parrot
Phylogenetics, biogeography and classification of, and character evolution in, gamebirds (Aves: Galliformes): effects of character exclusion, data partitioning and missing data
The phylogenetic relationships, biogeography and classification of, and morphobehavioral (M/B) evolution in, gamebirds (Aves: Galliformes) are investigated. In-group taxa (rooted on representatives of the Anseriformes) include 158 species representing all suprageneric galliform taxa and 65 genera. The characters include 102 M/B attributes and 4452 nucleic acid base pairs from mitochondrial cytochrome b (CYT B), NADH
dehydrogenase subunit 2 (ND2), 12S ribosomal DNA (12S) and control region (CR), and nuclear ovomucoid intron G (OVO-G). Analysis of the combined character data set yielded a single, completely resolved cladogram that had the highest levels of jackknife support, which suggests a need for a revised classification for the phasianine galliforms. Adding 102 M/B characters to the combined CYT B and ND2 partitions (2184 characters) decisively overturns the topology suggested by analysis of the two mtDNA partitions alone, refuting the view that M/B characters should be excluded from phylogenetic analyses because of their relatively small number and putative character state ambiguity. Exclusion of the OVO-G partition (with > 70% missing data) from the combined data set had no effect on cladistic structure, but slightly lowered jackknife support at several nodes. Exclusion of third positions of codons in an analysis of a CYT B + ND2 partition resulted in a massive loss of resolution and support, and even failed to recover the monophyly of the Galliformes with jackknife support. A combined analysis of putatively less informative, "non-coding" characters (CYT B/ND2 third position
sites + CR +12S + OVO-G sequences) yielded a highly resolved consensus cladogram congruent with the combined-evidence cladogram. Traditionally recognized suprageneric galliform taxa emerging in the combined cladogram are: the families Megapodiidae (megapodes), Cracidae (cracids), Numididae (guineafowls), Odontophoridae (New World quails) and Phasianidae (pheasants, pavonines, partridges, quails, francolins, spurfowls and grouse) and the subfamilies Cracinae (curassows, chachalacas and the horned guan), Penelopinae (remaining guans), Pavoninae sensu lato (peafowls, peacock pheasants and argus pheasants), Tetraoninae (grouse) and Phasianinae (pheasants minus Gallus). The
monophyly of some traditional groupings (e.g., the perdicinae: partridges/quails/francolins) is rejected decisively, contrasted by the emergence of other unexpected groupings. The most remarkable phylogenetic results are the placement of endemic African galliforms as sisters to geographically far-distant taxa in Asia and the
Americas. Biogeographically, the combined-data cladogram supports the hypothesis that basal lineages of galliforms diverged prior to the Cretaceous/Tertiary (K-T) Event and that the subsequent cladogenesis was influenced by the break-up of Gondwana. The evolution of gamebirds in Africa, Asia and the Americas has a far more complicated historical biogeography than suggested to date. With regard to character evolution: spurs appear to have evolved at least twice within the Galliformes; a relatively large number of tail feathers (â„ 14) at least three times; polygyny at least twice; and sexual dimorphism many times