Cytotaxonomic observations in tropical Vaccinieae (Ericaceae)

Chromosome numbers are reported for 36 accessions representing 31 species from nine genera of the tribe Vaccinieae, family Ericaceae. The plants are tropical and come from Southeast Asia and Central and South America. The taxonomy of the tribe is outlined in these regions. Genera are often poorly defined and taxa were chosen to reflect the range of variation of the Vaccinieae. Most Southeast Asian Vaccinium species were diploid (2 n = 24) as were those of Agapetes subgenus Agapetes (apart from the Himalayan A. flava ), Agapetes scortechinii and Costera endertii. All other accessions were found to be polyploid. The correlation between polyploidy, geographical distribution and the possession of an 'anatomical complex' of the leaf and stem in Vaccinieae of New Guinea and the neotropics is discussed.     

Phylogenetic relationships of russuloid basidiomycetes with emphasis on aphyllophoralean taxa

Many homobasidiomycetes are characterized by a combination of gloeocystidia and amyloid basidiospores. They display a great variation in basidioma morphology, including erect and effused forms and gilled and nongilled forms. Earlier studies have shown these taxa to be related, and the group has been named the russuloid clade. Phylogenetic relationships among russuloid basidiomycetes were investigated using sequence data from the nuclear 5.8S, ITS2 and large-subunit rDNA genes. A dataset including 127 ingroup sequences representing 43 genera and ca 120 species were analyzed by maximum-parsimony and neighbor-joining methods. The sampling of taxa had an emphasis on nongilled taxa and two-thirds of the species possessed corticioid basidiomata. Thirteen major well-supported clades were identified within the russuloid clade. All clades except one include corticioid species. Ten characters from basidioma morphology and cultured mycelium were observed and evaluated. Results suggest that gloeocystidia are a synapomorphy for taxa within the russuloid clade while the amyloidity of spores is inconsistent. The ornamentation of spores and type of nuclear behavior seems to be informative characters at genus level. The agaricoid genera Lactarius and Russula are nested in a clade with corticioid species at the basal position. The new combinations Boidinia aculeata, Gloeodontia subasperispora, Gloeocystidiopsis cryptacantha and Megalocystidium wakullum are proposed.     

The Ajellomycetaceae, a new family of vertebrate-associated Onygenales

Phylogenies inferred from the analysis of DNA sequence data have shown that the Onygenales contains clades that do not correspond with previously described families. One lineage identified in recent molecular phylogenetic studies includes the dimorphic pathogens belonging to the genera Ajellomyces, Emmonsia and Paracoccidioides. To evaluate the degree of support for this lineage and determine whether it includes additional taxa, we examined relationships among the members of this clade and selected saprobic onygenalean taxa based on maximum-parsimony analyses of partial nuclear large RNA subunit (LSU) and internal transcribed spacer (ITS) sequences. A clade distinct from the Onygenaceae was found to encompass Ajellomyces (including the anamorph genera Blastomyces, Emmonsia and Histoplasma) and Paracoccidioides brasiliensis. The members of this lineage are saprobic and pathogenic vertebrate-associated taxa distinguished by their globose ascomata with coiled appendages, muricate globose or oblate ascospores, and lack of keratinolytic activity. Anamorphs are solitary aleurioconidia or irregular alternate arthroconidia. Based on molecular data and on morphological and physiological similarities among these taxa, we propose the new family, Ajellomycetaceae.     

Phylogeny of the Spiny African Daisies (Compositae, tribe Arctotideae, subtribe Gorteriinae) based on trnL-F, ndhF, and ITS sequence data

The tribe Arctotideae (African Daisies), of the flowering plant family Compositae (Asteraceae), is a diverse and interesting group with a primarily southern African distribution (ca. 13 genera, 215 species) and many species in the Cape Floristic Region. It is divided into two subtribes: Arctotidinae (ca. 5 genera, 85 species) and Gorteriinae (ca. 8 genera, 130 species). The monophyly of the genera within the subtribe Gorteriinae and their relationship to one another was investigated using 71 samples/212 sequences including 64/141 of which are newly reported from three phylogenetic markers, two from chloroplast DNA (trnL-F and ndhF) and one from the nuclear genome (ITS). The outgroup was composed of seven members from the sister subtribe. Results show the subtribe Gorteriinae to be divided into three monophyletic groups, the Gazania-Hirpicium-Gorteria group, the Didelta group, and the Berkheya-Cullumia group. Within these three groups are 13 sub-groups, one of which has sub-clades. The genus Berkheya Ehrh. is paraphyletic, falling into five different sub-groups. The two monotypic genera, Cuspidia and Heterorhachis are not nested within any of the Berkheya clades. Hirpicium and Cullumia each have most of their taxa in a monophyletic group, but they also have one or two taxa associated with other clades. Four of the five sub-groups of Berkheya have morphologically recognizable shared characters, such as habit and spines that have been recognized by past studies. However, the grouping of one species with Didelta is difficult to explain. Support for the major clades and most of the sub-groups is strong but the relationships among some of the terminal taxa are variable.     

Phylogenetic relationships among species of Pichia, Issatchenkia and Williopsis determined from multigene sequence analysis, and the proposal of Barnettozyma gen. nov., Lindnera gen. nov. and Wickerhamomyces gen. nov

Relationships among species assigned to the yeast genera Pichia, Issatchenkia and Williopsis , which are characterized by the ubiquinone CoQ-7 and inability to utilize methanol, were phylogenetically analyzed from nucleotide sequence divergence in the genes coding for large and small subunit rRNAs and for translation elongation factor-1α. From this analysis, the species separated into five clades. Species of Issatchenkia are members of the Pichia membranifaciens clade and are proposed for transfer to Pichia . Pichia dryadoides and Pichia quercuum are basal members of the genus Starmera . Williopsis species are dispersed among hat-spored taxa in each of the remaining three clades, which are proposed as the new genera Barnettozyma, Lindnera and Wickerhamomyces . Lineages previously classified as varieties of Pichia kluyveri , ' Issatchenkia ' scutulata, Starmera amethionina and ' Williopsis ' saturnus are elevated to species rank based on sequence comparisons.     

Comparative Phyloclimatic Analysis and Evolution of Ecological Niches in the Scimitar Babblers (Aves: Timaliidae: Pomatorhinus)

We present the first extensive and integrative analysis of niche evolution based on climatic variables and a dated molecular phylogeny of a heterogeneous avian group of Southeast Asian scimitar babblers of the genus Pomatorhinus. The four main clades of scimitar babblers have species that co-occur in similar areas across southern Asia but some have diverged at different timeframes, with the most recently evolved clade harboring the highest number of species. Ecological niche models and analysis of contributing variables within a phylogenetic framework indicate instances of convergent evolution of members of different clades onto similar ecological parameter space, as well as divergent evolution of members from within clades. Pomatorhinus species from different clades occupying Himalayan foothills show convergence towards similar climatic tolerances, whereas within a clade, allopatric sister-species occurring in the Himalayas have diverged to occupy different climatic parameter spaces. Comparisons of climatic tolerances of Himalayan foothills taxa with species distributed further south in Assam/Burma and Burma/Thailand indicate convergence towards similar parameter spaces in several climatic variables. Niche overlap was observed to be lower among species of the youngest clade (ruficollis) and higher among species of older clades (ferruginosus). Analysis of accumulation of ecological disparity through time indicates rapid divergence within recent time frames. As a result, Himalayan taxa originating at different temporal scales within the four main scimitar babbler clades have differentiated ecologically only in recently diverged taxa. Our study suggests that the repeated orogenic and climatic fluctuations of the Pliocene and Pleistocene within mainland Southeast Asia served as an important ecological speciation driver within scimitar babblers, by providing opportunities for rapid geographic expansion and filling of novel environmental niches.     

The molecular phylogeny of aquatic hyphomycetes with affinity to the Leotiomycetes

Aquatic hyphomycetes play a key role in decomposition of submerged organic matter and stream ecosystem functioning. We examined the phylogenetic relationships among various genera of aquatic hyphomycetes belonging to the Leotiomycetes (Ascomycota) using sequences of internal transcribed spacer (ITS) and large subunit (LSU) regions of rDNA generated from 42 pure cultures including 19 ex-types. These new sequence data were analyzed together with additional sequences from 36 aquatic hyphomycetes and 60 related fungi obtained from GenBank. Aquatic hyphomycetes, characterized by their tetraradiate or sigmoid conidia, were scattered in nine supported clades within the Helotiales (Leotiomycetes). Tricladium, Lemonniera, Articulospora, Anguillospora, Varicosporium, Filosporella, and Flagellospora are not monophyletic, with species from the same genus distributed among several major clades. The Gyoerffyella clade and the Hymenoscyphus clade accommodated species from eight and six different genera, respectively. Thirteen aquatic hyphomycete taxa were grouped in the Leotia-Bulgaria clade while twelve species clustered within the Hymenoscyphus clade along with several amphibious ascomycetes. Species of Filosporella and some species from four other aquatic genera were placed in the Ascocoryne-Hydrocina clade. It is evident that many aquatic hyphomycetes have relatives of terrestrial origin. Adaptation to colonize the aquatic environment has evolved independently in multiple phylogenetic lineages within the Leotiomycetes.     

A comprehensive molecular phylogeny of the starlings (Aves: Sturnidae) and mockingbirds (Aves: Mimidae): congruent mtDNA and nuclear trees for a cosmopolitan avian radiation

We generated a comprehensive phylogeny for the avian families Sturnidae (starlings, mynas, Rhabdornis, oxpeckers, and allies) and Mimidae (mockingbirds, thrashers, and allies) to explore patterns of morphological and behavioral diversification. Reconstructions were based on mitochondrial DNA sequences from five coding genes (4108 bp), and nuclear intron sequences from four loci (2974 bp), for most taxa, supplemented with NDII gene sequences (1041 bp) derived from museum skin specimens from additional taxa; together the 117 sampled taxa comprise 78% of the 151 species in these families and include representatives of all currently or recently recognized genera. Phylogenetic analyses consistently identified nine major clades. The basal lineage is comprised of the two Buphagus oxpeckers, which are presently confined to Africa where they are obligately associated with large mammals. Some species in nearly all of the other major clades also feed on or around large vertebrates, and this association may be an ancestral trait that fostered the world-wide dispersal of this group. The remaining taxa divide into sister clades representing the New-World Mimidae and Old-World Sturnidae. The Mimidae are divided into two subclades, a group of Central American and West Indian catbirds and thrashers, and a pan-American clade of mockingbirds and thrashers. The Sturnidae are subdivided into six clades. The Phillipine endemic Rhabdornis are the sister lineage to a larger and substantially more recent radiation of South Asian and Pacific island starlings and mynas. A clade of largely migratory or nomadic Eurasian starlings (within which the basal lineage is the model taxon Sturnus vulgaris) is allied to three groups of largely African species. These reconstructions confirm that Buphagus should not be included in the Sturnidae, and identify many genera that are not monophyletic. They also highlight the substantial diversity among the major Sturnidae subclades in rates of species accumulation, morphological differentiation, and behavioral variation.     

Cytotaxonomic observations in tropical Vaccinieae (Ericaceae)

Chromosome numbers are reported for 36 accessions representing 31 species from nine genera of the tribe Vaccinieae, family Ericaceae. The plants are tropical and come from Southeast Asia and Central and South America. The taxonomy of the tribe is outlined in these regions. Genera are often poorly defined and taxa were chosen to reflect the range of variation of the Vaccinieae. Most Southeast Asian Vaccinium species were diploid (2n= 24) as were those of Agapetes subgenus Agapetes (apart from the Himalayan A. flava), Agapetes scortechinii and Costera endertii. All other accessions were found to be polyploid. The correlation between polyploidy, geographical distribution and the possession of an ‘anatomical complex’ of the leaf and stem in Vaccinieae of New Guinea and the neotropics is discussed.     

A phylogenetic analysis of the palm subtribe Oncospermatinae (Arecaceae) based on morphological characters

Subtribe Oncospermatinae (Arecaceae: Arecoideae: Areceae) is a diverse group of spiny Old World palms. The subtribe includesOncosperma, a widespread Asian genus of five species, along with seven monotypic genera, all endemic to the Seychelles and Mascarene Islands of the western Indian Ocean. A phylogenetic analysis was conducted in order to test the monophyly of subtribe Oncospermatinae with respect to other Old World genera of tribe Areceae. A matrix of 38 morphological characters was scored for 29 taxa, including 11 species of the Oncospermatinae. A single most parsimonious tree was found, resolving the subtribe as a polyphyletic group of two distinct clades. One clade containingAcanthophoenix, Deckenia, Oncosperma, andTectiphiala was placed as sister to a large group that includes members of subtribes Archontophoenicinae, Arecinae, Iguanurinae, and Ptychospermatinae. The other clade of Oncospermatinae, including the Seychelles endemic generaNephrosperma, Phoenicophorium, Roscheria, andVerschaffeltia, was resolved as sister to the Madagascar endemic subtribe Masoalinae, and may have arisen in the western Indian Ocean region.     

Phylogeny of Neotropical oryzomyine rodents (Muridae: Sigmodontinae) based on the nuclear IRBP exon

Sigmodontine rodents are the most diverse family-level mammalian clade in the Neotropical region, with about 70 genera and 320 recognized species. Partial sequences (1266 bp) from the first exon of the nuclear gene encoding the Interphotoreceptor Retinoid Binding Protein (IRBP) were used to infer the phylogenetic relationships among 44 species representing all 16 currently recognized genera of the largest sigmodontine tribe, the Oryzomyini. Monophyly of the tribe was assessed relative to 15 non-oryzomyine sigmodontine taxa representing all major sigmodontine lineages. Twelve taxa from seven muroid subfamilies were used as outgroups. The resulting matrix included 71 taxa and 386 parsimony-informative characters. Phylogenetic analysis of this matrix resulted in 16 equally parsimonious cladograms, which contained the following well-supported groups: (i). a monophyletic Oryzomyini, (ii). a clade containing all oryzomyines except Scolomys and Zygodontomys, (iii). a clade containing Oecomys, Handleyomys, and several species of forest-dwelling Oryzomys, and (iv). a clade containing the remaining oryzomyine taxa. The last clade is composed of two large subclades, each with lower nodal support, containing the following taxa: (i). Microryzomys, Oligoryzomys, Neacomys, and Oryzomys balneator; (ii). Holochilus, Lundomys, Pseudoryzomys, Nectomys, Amphinectomys, Sigmodontomys, and several species of open-vegetation or semiaquatic Oryzomys. Regarding relationships among non-oryzomyine taxa, sigmodontines, neotomines, and tylomyines do not form a monophyletic group; a clade containing Rheomys and Sigmodon is basal relative to all other sigmodontines; and the remaining sigmodontines are grouped in three clades: the first containing Thomasomyini, Akodontini, and Reithrodon; the second containing Abrothrichini, and Phyllotini, plus Wiedomys, Juliomys, Irenomys, and Delomys; and the third containing the oryzomyines. No conflict is observed between IRBP results and previous robust hypotheses from mitochondrial data, while a single case of incongruence is present between the IRBP topology and robust hypothesis from morphological studies.     

Evolutionary relationships among the protostrongylidae (Nematoda: Metastrongyloidea) as inferred from morphological characters, with consideration of parasite-host coevolution.

The phylogeny of nematodes in the family Protostrongylidae (Nematoda: Metastrongyloidea) was reconstructed by cladistic analysis of 28 binary and multistate characters derived from comparative morphology. Analyses were hierarchical, and examined (1) relationships among genera, including 13 ingroup taxa and Metastrongylidae as an outgroup (single tree, 78 steps, consistency index [CI] = 0.705); and (2) relationships among genera and species groups, including 21 ingroup taxa and Metastrongylus apri as an outgroup (single tree, 76 steps, CI = 0.582). In the species-level tree, Protostrongylidae was divided into 2 major clades, 1 containing the subfamilies Muelleriinae (including the recently described Umingmtakstrangylus pallikuukensis), Elaphostrongylinae, and the Varestrongylinae (excluding Pneumocaulus kadenazii). Varestrongylus was paraphyletic as it included Pneumostrongylus calcaratus. The second major clade consisted of a paraphyletic group containing Protostrongylus spp. and Spiculocaulus leuckarti and, basal to this subclade, several other individual protostrongylid lineages. The various subclades generally correspond to the subfamilial divisions of the Protostrongylidae. The Neostrongylinae, however, is not supported as Neostrongylus and Orthostrongylus are not sister groups. Based on a large number of hypothesized synapomorphies, the elaphostrongylines appear to be a highly derived group of protostrongylids, a feature potentially correlated with their habitat localization in muscular and nervous tissues. The generic-level tree retained most of the primary structure revealed among the species but excluded the varestrongylines from the Muelleriinae + Elaphostrongylinae subclade. Artiodactyles of the family Cervidae are considered basal hosts for protostrongylids; secondary colonization in Caprini, Rupicaprini, and among lagomorphs is postulated.     

Phylogeny and character evolution in the Empidonax group of tyrant flycatchers (Aves: Tyrannidae): a test of W. E. Lanyon's hypothesis using mtDNA sequences

We sequenced mitochondrial DNA from four protein-coding genes for 26 taxa to test W. E. Lanyon's hypothesis of intergeneric relationships and character evolution in the Empidonax group of tyrant flycatchers. Three genera in this group (Empidonax, Contopus, and Sayornis) successfully occupy north temperate habitats for breeding, while the remaining genera (Mitrephanes, Cnemotriccus, Aphanotriccus, Lathrotriccus, and Xenotriccus) are restricted to neotropical latitudes. Lanyon hypothesized two major clades in the group based on differences in syringeal morphology and proposed relationships among genera using a combination of morphologic, behavioral, and allozymic characters. The mtDNA data strongly support Lanyon's division of genera into two clades. In addition, the molecular and nonmolecular data sets agree in uniting Aphanotriccus and Lathrotriccus as sister taxa, with Cnemotriccus as basal to these genera. Species of Aphanotriccus, Lathrotriccus, and Cnemotriccus form a clade that exploits a distinctive nesting niche relative to other members of the Empidonax group. Within the second major clade, mtDNA sequences support a reconstruction based on allozymes that places Contopus and Empidonax as sister taxa. This hypothesis contradicts that of Lanyon, who allied Contopus with Mitrephanes on the basis of similarity in foraging mode. Genera in the Empidonax group are members of a larger assemblage that radiated in South America. Occupancy of temperate habitats by certain genera in this group is coincident with their evolution of migratory behavior and with independent diversification in foraging modes that reduces potential competition in sympatry.     

Molecular systematics of a speciose, cosmopolitan songbird genus: defining the limits of, and relationships among, the Turdus thrushes

The avian genus Turdus is one of the most speciose and widespread of passerine genera. We investigated phylogenetic relationships within this genus using mitochondrial DNA sequence data from the ND3, ND2 and cytochrome b genes. Our sampling of Turdus included 60 of the 65 extant species currently recognized, as well as all four species from three genera previously shown to fall inside Turdus (Platycichla, Nesocichla, and Cichlherminia). Phylogenetic trees based on maximum likelihood and maximum parsimony algorithms were congruent. Most of the Turdus taxa sampled fall into one of four clades: an African clade, a Central American-Caribbean clade, a largely South American clade, and a Eurasian clade. Still other taxa are placed either at the base of Turdus, or as links between clades. In no instance is any continent reciprocally monophyletic for the species distributed on it. A general lack of nodal support near the base of the phylogeny seems related to a rapid intercontinental establishment of the major clades within Turdus very early in the history of the genus. The monotypic genus Psophocichla is distantly related to, but clearly the sister of, Turdus rather than a constituent member of it.     

Evidence for host-specific clades of tetraphyllidean tapeworms (Platyhelminthes: Eucestoda) revealed by analysis of 18S ssrDNA

Sequence data from the V4 and V7-V9 variable regions of the 18S small subunit ribosomal DNA (ssrDNA) gene were used to examine relationships among 26 tetraphyllidean and two lecanicephalidean taxa. Newly collected specimens of 21 of the tetraphyllidean species were used to generate ssrDNA sequences that were combined with sequences previously available, including those of two diphyllidean taxa used for outgroup rooting. The sequences were aligned by eye according to secondary structural motifs of the conserved core of the molecule. Of the 1520 sites in the alignment, 874 (58%) were excluded from analysis due to alignment gaps and lack of positional homology as inferred by manual inspection. Genetic variability of the ssrDNA gene regions compared was greater than would be expected, based on the present taxonomy of the ingroup species, and the genetic divergences among tetraphyllidean 'families' and genera were comparable to that among tapeworm orders. Phylogenetic hypotheses were generated by the methods of maximum parsimony and maximum likelihood (GTR + I + Gamma nucleotide substitution model). Four most parsimonious trees resulted from analysis by maximum parsimony. Strict consensus of the four trees supported the monophyly of the Tetraphyllidea, with the lecanicephalidean taxa forming a sister lineage. Among the tetraphyllidean taxa included in the analysis were three major clades: a basal clade including species of the phyllobothriid genera Anthocephalum, Echeneibothrium, Rhinebothrium, Rhodobothrium and Spongiobothrium; a clade uniting the phyllobothriids of the genus Duplicibothrium with the dioecotaeniid genus Dioecotaenia; and a larger sister clade to the Duplicibothrium + Dioecotaenia clade that included the phyllobothriid genera Caulohothrium, Ceratobothrium, Clistobothrium, Paraoryigmatobothrium and Prosobothrium, the litobothriid genus Litobothrium and the onchobothriid genera Acanthobothrium, Calliobothrium, Phoreiobothrium and Platybothrium. Maximum likelihood analysis resulted in a topology that was congruent where nodes were strongly supported by parsimony analysis, but differed in the relative positions of the well-supported clades. In addition,maximum likelihood analysis grouped the lecanicephalidean taxa among the tetraphyllidean taxa, indicating paraphyly of the order Tetraphyllidea as currently defined. Relationships suggested by both methods of analysis reflected common host associations of the taxa better than their current classification, suggesting that coevolution has had a significant role in the evolution of the group.     

Phylogeny of Melaleuca, Callistemon, and Related Genera of the Beaufortia Suballiance (Myrtaceae) Based on 5S and ITS-1 Spacer Regions of nrDNA

A phylogenetic analysis of genera within the informal suballiance Beaufortia (family Myrtaceae), largely endemic to Australia and New Caledonia, is presented based on separate and combined data sets for 5S and ITS-1 spacer regions of nuclear ribosomal DNA. The two sets were not in conflict but the 5S data set was more informative. Data were analysed using conventional parsimony, jackknife parsimony, and three-item parsimony analyses. Three-item analysis gave more resolved trees than conventional parsimony analysis. The Beaufortia suballiance includes two major clades, with all Australian representatives of Callistemon (shown to be monophyletic) and most Australian representatives of Melaleuca forming one of these. The sister clade comprises a well-defined group of endemic New Caledonian taxa (classified as Callistemon and Melaleuca ), some Australian species of Melaleuca , a clade including the Western Australia/Northern Territory genera Beaufortia, Lamarchea , and Regelia , and a clade including the south-west Western Australian genera Calothamnus, Eremaea, Conothamnus , and Phymatocarpus . All molecular analyses sup port the monophyly of Conothamnus and of Regelia , genera for which a number of species were included. Three-item analysis of the combined data set supports the monophyly of Beaufortia . The findings have implications for both taxonomy and biogeography.     

Phylogeny of the parasitic plant family Orobanchaceae inferred from phytochrome A

Partial sequences of the nuclear gene encoding the photoreceptor phytochrome A (PHYA) are used to reconstruct relationships within Orobanchaceae, the largest of the parasitic angiosperm families. The monophyly of Orobanchaceae, including nonphotosynthetic holoparasites, hemiparasites, and nonparasitic Lindenbergia is strongly supported. Phytochrome A data resolve six well-supported lineages that contain all of the sampled genera except Brandisia, which is sister to the major radiation of hemiparasites. In contrast to previous plastid and ITS trees, relationships among these major clades also are generally well supported. Thus, the robust phylogenetic hypothesis inferred from the PHYA data provides a much better context in which to evaluate the evolution of parasitism within the group. Ninety-eight species of Orobanchaceae, representing 43 genera, are included and Brandisia, Bungea, Cymbaria, Esterhazya, Nesogenes, Phtheirospermum, Radamaea, Siphonostegia, and Xylocalyx are confirmed as members of Orobanchaceae. The earliest diverging lineage of hemiparasites is identified for the first time; it contains Bungea, Cymbaria, Monochasma, Siphonostegia, and the monotypic Schwalbea, which is federally endangered. This basal clade is marked by the presence of two novel introns. A second, apparently independent gain of one of these introns marks a clade of largely European taxa. There is significant rate heterogeneity among PHYA sequences, and the presence of multiple PHYA in some taxa is consistent with observed ploidy levels.     

One size does not fit all: no evidence for an optimal body size on islands

Aim Optimal body size theories predict that large clades have a single, optimal, body size that serves as an evolutionary attractor, with the full body size spectrum of a clade resulting from interspecific competition. Because interspecific competition is believed to be reduced on islands, such theories predict that insular animals should be closer to the optimal size than mainland animals. We test the resulting prediction that insular clade members should therefore have narrower body size ranges than their mainland relatives. Location World‐wide. Methods We used body sizes and a phylogenetic tree of 4004 mammal species, including more than 200 species that went extinct since the last ice age. We tested, in a phylogenetically explicit framework, whether insular taxa converge on an optimal size and whether insular clades have narrow size ranges. Results We found no support for any of the predictions of the optimal size theory. No specific size serves as an evolutionary attractor. We did find consistent evidence that large (> 10 kg) mammals grow smaller on islands. Smaller species, however, show no consistent tendency to either dwarf or grow larger on islands. Size ranges of insular taxa are not narrower than expected by chance given the number of species in their clades, nor are they narrower than the size ranges of their mainland sister clades – despite insular clade members showing strong phylogenetic clustering. Main conclusions The concept of a single optimal body size is not supported by the data that were thought most likely to show it. We reject the notion that inclusive clades evolve towards a body‐plan‐specific optimum.     

Recent Bryological Literature

Abstract

Members of the moss family Hylocomiaceae have been hypothesized to belong to more than one major clade. While molecular studies performed so far are inconclusive regarding Hylocomiaceae relationships, morphological data are used here to test this hypothesis, based on species representing all genera of the Hylocomiaceae as well as some genera that possibly belong to this family. The results of the analysis suggest that Hylocomiaceae members belong to two major clades, one including mainly northern temperate species and one mainly tropical to subtropical taxa, with most of the latter species found in S.E. Asia. With the morphological context provided here, the next step in the investigation of this family should include both studies of more taxa outside the family, to correctly infer the phylogenetic relationships in a larger framework, and the addition of data from several molecular markers belonging to more than one genome.