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At least 577 records · Page 32Linked to original sources
PubMed2006

Molecular systematics of basal subfamilies of ants using 28S rRNA (Hymenoptera: Formicidae).

For many years, the ant subfamily Ponerinae was hypothesized to contain the basal (early branching) lineages of ants. Recently the Ponerinae were reclassified into six poneromorph subfamilies based on morphological analysis. We evaluate this new poneromorph classification using 1240 base pairs of DNA sequence data obtained from 28S rRNA gene sequences of 68 terminal taxa. The molecular tree supported the monophyly of the ant family Formicidae, with 100% parsimony bootstrap (PB) support and posterior probabilities (PP) of 1.00, with the ant subfamily Leptanillinae as a sister group to all other ants (PB=62, PP=93). However, our analyses strongly support the polyphyly of the Poneromorph subfamilies (sensu Bolton). The Ectatomminae and Heteroponerinae are more closely related to the Formicoid subfamilies than to the rest of the poneromophs (PB=96, PP=100). The Amblyoponinae (PB=52, PP=96), Paraponerinae (PB=100, PP=100), Ponerinae (PB<50, PP=71), and Proceratiinae (PB=98, PP=100) appear as distinct lineages at the base of the tree and are identified as a poneroid grade. Monophyletic origins for the poneroid subfamilies Amblyoponinae, Paraponerinae, Ponerinae and Proceratiinae are supported in our analysis. However, the genus Platythyrea forms a distinct sister group to the Ponerini within the Ponerinae. The Heteroponerinae, based on our sample of Heteroponera, are associated with the subfamily Ectatomminae (PB=98, PP=100). Furthermore, our data indicate the genus Probolomyrmex belongs to the Proceratiinae as suggested by recent morphological analysis (PB=98, PP=100).

Animals↗
PubMed1995

Cladistic analyses of combined traditional and molecular data sets reveal an algal lineage.

The chromophyte algae are a large and biologically diverse assemblage of brown seaweeds, diatoms, and other golden algae classified in 13 taxonomic classes. One subgroup (diatoms, pedinellids, pelagophytes, silicoflagellates, and certain enigmatic genera) is characterized by a highly reduced flagellar apparatus. The flagellar apparatus lacks microtubular and fibrous roots, and the flagellum basal body is attached directly to the nucleus. We hypothesize that the flagellar reduction is the result of a single evolutionary series of events. Cladistic analysis of ultrastructural and biochemical data reveals a monophyletic group that unites all taxa with a reduced flagellar apparatus, supporting our hypothesis. Phylogenetic analyses of 18S rRNA gene sequence data provide strong resolution within most of the major groups of chromophytes but only weakly resolve relationships among those groups. Some of the molecularly based most parsimonious trees, however, also unite the taxa with a reduced flagellar apparatus, although the diatoms are not included in this lineage. This grouping is further supported by a posteriori character weighting of the molecular data, suggesting that flagellar reduction occurred at least twice in parallel evolutionary series of events. To further test our hypothesis of a single evolutionary reduction in the flagellar apparatus, we combine the two data sets and subject the hybrid data matrix to parsimony analysis. The resulting trees unite the diatoms with the other reduced flagellar apparatus algae in a monophyletic group. This result supports our hypothesis of a single evolutionary reduction and indicates the existence of a previously unrecognized lineage of algae characterized by a highly reduced flagellar apparatus. Further, this study suggests that the traditional classification of the diatoms with the chrysophytes and xanthophytes in the division (= phylum) Chrysophyta, as presented in most textbooks, is unsatisfactory and that a significantly different classification should be employed.

Base Sequence↗
PubMed2002

An algorithm for detecting directional and non-directional positive selection, neutrality and negative selection in protein coding DNA sequences.

Positive selection or adaptive evolution is thought to be responsible, at least some of the time, for the rapid accumulation of advantageous changes in protein-coding genes. The origin of new enzymatic functions, erection of barriers to heterospecific fertilization, and evasion of host response by pathogens, among other things, are thought to be instances of adaptive evolution. Detecting positive selection in protein-coding genes is fraught with difficulties. Saturation for sequence change, codon usage bias, ephemeral selection events and differential selective pressures on amino acids all contribute to the problem. A number of solutions have been proposed with varying degrees of success, however they suffer from limitations of not being accurate enough or being prohibitively computationally intensive. We have developed a character-based method of identifying lineages that undergo positive selection. In our method we assess the possibility that for each internal branch of a phylogenetic tree an event occurred that subsequently gave rise to a greater number of replacement substitutions than might be expected. We classify these replacement substitutions into two categories - whether they subsequently became invariable or changed again in at least one descendent lineage. The former situation indicates that the new character state is under strong selection to preserve its new identity (directional selection), while the latter situation indicates that there is a persistent pressure to change identity (non-directional selection). The method is fast and accurate, easy to implement, sensitive to short-lived selection events and robust with respect to sampling density and proportion of sites under the influence of positive selection.

Algorithms↗
PubMed2000

Genetic diversity of oceanic island Lasaea (Mollusca: Bivalvia) lineages exceeds that of continental populations in the northwestern Atlantic.

Direct-developing lineages of the intertidal marine bivalve Lasaea have colonized both upstream mainland (southeastern Florida) and downstream oceanic island (Bermuda) locations in the western North Atlantic. Replicate samples from these two regional populations, separated by about 1500 km of open ocean, were sequenced for a 655-nucleotide portion of the mitochondrial (mt) cytochrome oxidase subunit I gene. Twelve haplotypes (2 Floridian and 10 Bermudan) were obtained that differed by a maximum of four substitutions among pairwise comparisons. Phylogenetic analysis yielded a parsimony network within which the mainland lineages clustered in one of the terminal branches; a mirror image of a priori expectations based on regional surface-current polarity. It is difficult, however, to envisage a plausible countercurrent dispersal mechanism. This tree topology may stem from divergent demographic processes operating on these two evolutionarily recent regional populations. The starlike phylogenetic pattern of Bermudan lineages is consistent with a history of rapid population growth. The restricted genetic repertoire and relative ecological scarcity of Floridian lineages imply either a recent founder event by unstudied Caribbean source populations or else a history of pronounced bottlenecks in population size. Bermuda's impoverished Caribbean marine biota may allow western North Atlantic Lasaea lineages to escape severe competitive interactions impacting other parts of their geographic range.

Animals↗
PubMed1991

Plastid genomes of the Rhodophyta and Chromophyta constitute a distinct lineage which differs from that of the Chlorophyta and have a composite phylogenetic origin, perhaps like that of the Euglenophyta.

A phylogenetic tree has been constructed from comparisons of entire 16S rRNA gene sequences from different prokaryotes and from several algal plastids. According to this study, and to previous work on the ribulose-1,5-bisphosphate carboxylase oxygenase (Rubisco) large and small subunit genes, we postulate that: (1) rhodophyte and chromophyte plastid genomes have a common, composite phylogenetic origin which implies at least two different ancestors, a cyanobacterial and a beta-proteobacterial ancestor; (2) chlorophyte (green algae and land plants) plastids have a cyanobacterial ancestor which probably differs from that of rhodophyte and chromophyte plastids, and in any case constitute a different lineage; (3) euglenophyte plastid genomes also seem to have a composite phylogenetic origin which involves two different lineages.

Base Sequence↗
PubMed2025

Genetically distinct within-host subpopulations of hepatitis C virus persist after Direct-Acting Antiviral treatment failure.

Analysis of viral genetic data has previously revealed distinct within-host population structures in both untreated and interferon-treated chronic hepatitis C virus (HCV) infections. While multiple subpopulations persisted during the infection, each subpopulation was observed only intermittently. However, it was unknown whether similar patterns were also present after Direct-Acting Antiviral (DAA) treatment, where viral populations were often assumed to go through narrow bottlenecks. Here we tested for the maintenance of population structure after DAA treatment failure, and whether there were different evolutionary rates along distinct lineages where they were observed. We analysed whole-genome next-generation sequencing data generated from a randomised study using DAAs (the BOSON study). We focused on samples collected from patients (N=84) who did not achieve sustained virological response (i.e., treatment failure) and had sequenced virus from multiple timepoints. Given the short-read nature of the data, we used a number of methods to identify distinct within-host lineages including tracking concordance in intra-host nucleotide variant (iSNV) frequencies, applying sequenced-based and tree-based clustering algorithms to sliding windows along the genome, and haplotype reconstruction. Distinct viral subpopulations were maintained among a high proportion of individuals post DAA treatment failure. Using maximum likelihood modelling and model comparison, we found an overdispersion of viral evolutionary rates among individuals, and significant differences in evolutionary rates between lineages within individuals. These results suggest the virus is compartmentalised within individuals, with the varying evolutionary rates due to different viral replication rates and/or different selection pressures. We endorse lineage awareness in future analyses of HCV evolution and infections to avoid conflating patterns from distinct lineages, and to recognise the likely existence of unsampled subpopulations.

Humans↗
PubMed2004

Detection of lateral gene transfer events in the prokaryotic tRNA synthetases by the ratios of evolutionary distances method.

The availability of large numbers of genomic sequences has demonstrated the importance of lateral gene transfer (LGT) in prokaryotic evolution. However, considerable uncertainty remains concerning the frequency of LGT compared to other evolutionary processes. To examine LGTs in ancient lineages of prokaryotes a method was developed that utilizes the ratios of evolutionary distances (RED) to distinguish between alternative evolutionary histories. The advantages of this approach are that the variability inherent in comparing protein sequences is transparent, the direction of LGT and the relative rates of evolution are readily identified, and it is possible to detect other types of evolutionary events. This method was standardized using 35 genes encoding ribosomal proteins that were believed to share a vertical evolution. Using RED-T, an original computer program designed to implement the RED method, the evolution of the genes encoding the 20 aminoacyl-tRNA synthetases was examined. Although LGTs were common in the evolution of the aminoacyl-tRNA synthetases, they were not sufficient to obscure the organismal phylogeny. Moreover, much of the apparent complexity of the gene tree was consistent with the formation of the paralogs in the ancestors to the modern lineages followed by more recent loss of one paralog or the other.

Amino Acid Sequence↗
PubMed2000

Archaic lineages in the history of modern humans.

An important question in the ongoing debate on the origin of Homo sapiens is whether modern human populations issued from a single lineage or whether several, independently evolving lineages contributed to their genetic makeup. We analyzed haplotypes composed of 35 polymorphisms from a segment of the dystrophin gene. We find that the bulk of a worldwide sample of 868 chromosomes represents haplotypes shared by different continental groups. The remaining chromosomes carry haplotypes specific for the continents or for local populations. The haplotypes specific for non-Africans can be derived from the most frequent ones through simple recombination or a mutation. In contrast, chromosomes specific for sub-Saharan Africans represent a distinct group, as shown by principal component analysis, maximum likelihood tree, structural comparison, and summary statistics. We propose that African chromosomes descend from at least two lineages that have been evolving separately for a period of time. One of them underwent range expansion colonizing different continents, including Africa, where it mixed with another, local lineage represented today by a large fraction of African-specific haplotypes. Genetic admixture involving archaic lineages appears therefore to have occurred within Africa rather than outside this continent, explaining greater diversity of sub-Saharan populations observed in a variety of genetic systems.

Africa↗
PubMed2004

The utility of AFLPs for supporting mitochondrial DNA phylogeographical analyses in the Taiwanese bamboo viper, Trimeresurus stejnegeri.

An amplified fragment length polymorphism (AFLP) assay was performed on individuals representing discrete haplotypes from two genetically distinct mtDNA lineages of the bamboo viper, Trimeresurus stejnegeri (Schmidt), within Taiwan. AFLP (525 polymorphic markers from five primer pairs) and mtDNA genetic distances were highly correlated and an analysis of molecular variance, and a Bayesian approach similarly partitioned estimates of genetic similarity according to the mtDNA phylogeographical pattern. These results are discussed in relation to biogeographical hypotheses, comparative rates of mtDNA molecular evolution, and in the identification of evolutionary significant units of Taiwanese T. stejnegeri. In spite of the high degree of congruence between the genetic datasets, the AFLP phylogenetic analysis did not support the mtDNA tree, suggesting that no contemporary barriers to gene flow exist between individuals from the two mtDNA lineages.

Analysis of Variance↗
PubMed2002

Phylogeographic analysis of the cornsnake (Elaphe guttata) complex as inferred from maximum likelihood and Bayesian analyses.

Most phylogeographic studies have used maximum likelihood or maximum parsimony to infer phylogeny and bootstrap analysis to evaluate support for trees. Recently, Bayesian methods using Marlov chain Monte Carlo to search tree space and simultaneously estimate tree support have become popular due to its fast search speed and ability to create a posterior distribution of parameters of interest. Here, I present a study that utilizes Bayesian methods to infer phylogenetic relationships of the cornsnake (Elaphe guttata) complex using cytochrome b sequences. Examination of the posterior probability distributions confirms the existence of three geographic lineages. Additionally, there is no support for the monophyly of the subspecies of E. guttata. Results suggest the three geographic lineages partially conform to the ranges of previously defined subspecies, although Shimodaira-Hasegawa tests suggest that subspecies-constrained trees produce significantly poorer likelihood estimates than the most likely trees reflecting the evolution of three geographic assemblages. Based on molecular support, these three geographic assemblages are recognized as species using evolutionary species criteria: E. guttata, Elaphe slowinskii, and Elaphe emoryi [phylogeographic, maximum likelihood, maximum parsimony, bootstrap, Bayesian, Markov chain Monte Carlo, cornsnake, Cytochrome b, geographic lineages, E. guttta, E. slowinskii, and E. emoryi].

Animals↗
PubMed2005

Bats, clocks, and rocks: diversification patterns in Chiroptera.

Identifying nonrandom clade diversification is a critical first step toward understanding the evolutionary processes underlying any radiation and how best to preserve future phylogenetic diversity. However, differences in diversification rates have not been quantitatively assessed for the majority of groups because of the lack of necessary analytical tools (e.g., complete species-level phylogenies, estimates of divergence times, and robust statistics which incorporate phylogenetic uncertainty and test appropriate null models of clade growth). Here, for the first time, we investigate diversification rate heterogeneity in one of the largest groups studied thus far, the bats (Mammalia: Chiroptera). We use a recent, robust statistical approach (whole-tree likelihood-based relative rate tests) on complete dated species-level supertree phylogenies. As has been demonstrated previously for most other groups, among-lineage diversification rate within bats has not been constant. However, we show that bat diversification is more heterogeneous than in other mammalian clades thus far studied. The whole-tree likelihood-based relative rates tests suggest that clades within the families Phyllostomidae and Molossidae underwent a number of significant changes in relative diversification rate. There is also some evidence for rate shifts within Pteropodidae, Emballonuridae, Rhinolophidae, Hipposideridae, and Vespertilionidae, but the significance of these shifts depends on polytomy resolution within each family. Diversification rate in bats has also not been constant, with the largest diversification rate shifts occurring 30-50 million years ago, a time overlapping with the greatest number of shifts in flowering plant diversification rates.

Animals↗
PubMed2006

Basal relationships in the Drosophila melanogaster species group.

The Drosophila melanogaster species group is a popular model for evolutionary studies due to its morphological and ecological diversity and its inclusion of the model species D. melanogaster. However, phylogenetic relationships among major lineages within this species group remain controversial. In this report, the phylogeny of 10 species representing each of the well-supported monophyletic clades in the melanogaster group was studied using the sequences of 14 loci that together comprise 9493 nucleotide positions. Combined Bayesian analysis using gene-specific substitution models produced a 100% credible set of two trees. In the strict consensus of these trees, the ananassae subgroup branches first in the melanogaster species group, followed by the montium subgroup. The remaining lineages form a monophyletic clade in which D. ficusphila and D. elegans branch first, followed by D. biarmipes, D. eugracilis, and the melanogaster subgroup. This strongly supported phylogeny resolves most basal relationships in the melanogaster species group, and provides a framework that can be extended in the future to encompass more species.

Animals↗
PubMed2000

Early-branching or fast-evolving eukaryotes? An answer based on slowly evolving positions.

The current paradigm of eukaryotic evolution is based primarily on comparative analysis of ribosomal RNA sequences. It shows several early-emerging lineages, mostly amitochondriate, which might be living relics of a progressive assembly of the eukaryotic cell. However, the analysis of slow-evolving positions, carried out with the newly developed slow-fast method, reveals that these lineages are, in terms of nucleotide substitution, fast-evolving ones, misplaced at the base of the tree by a long branch attraction artefact. Since the fast-evolving groups are not always the same, depending on which macromolecule is used as a marker, this explains most of the observed incongruent phylogenies. The current paradigm of eukaryotic evolution thus has to be seriously re-examined as the eukaryotic phylogeny is presently best summarized by a multifurcation. This is consistent with the Big Bang hypothesis that all extant eukaryotic lineages are the result of multiple cladogeneses within a relatively brief period, although insufficiency of data is also a possible explanation for the lack of resolution. For further resolution, rare evolutionary events such as shared insertions and/or deletions or gene fusions might be helpful.

Actins↗
PubMed2004

Tracing the decay of the historical signal in biological sequence data.

Alignments of nucleotide or amino acid sequences may contain a variety of different signals, one of which is the historical signal that we often try to recover by phylogenetic analysis. Other signals, such as those arising due to compositional heterogeneities, among-lineage and among-site rate heterogeneities, invariant sites, and covariotides, may interfere adversely with the recovery of the historical signal. The effect of the interaction of these signals on phylogenetic inference is not well understood and may, in many cases, even be underappreciated. In this study, we investigate this matter and present results based on Monte Carlo simulations. We explored the success of four phylogenetic methods in recovering the true tree from data that had evolved under conditions where the equilibrium base frequencies and substitution rates were allowed to vary among lineages. Seven scenarios with increasingly complex conditions were investigated. All of the methods tested, with the exception of neighbor-joining using LogDet distances, were sensitive to compositional convergence in nonsister lineages. Maximum parsimony was also susceptible to attraction between long edges. In many cases, however, phylogenetic inference methods can still recover the true tree when misleading signals are present, in some instances even when the historical signal is no longer dominant. These results highlight the growing need for simple methods to detect violation of the phylogenetic assumptions.

Amino Acid Sequence↗
PubMed2006

Core set approach to reduce uncertainty of gene trees.

BACKGROUND: A genealogy based on gene sequences within a species plays an essential role in the estimation of the character, structure, and evolutionary history of that species. Because intraspecific sequences are more closely related than interspecific ones, detailed information on the evolutionary process may be available by determining all the node sequences of trees and provide insight into functional constraints and adaptations. However, strong evolutionary correlations on a few lineages make this determination difficult as a whole, and the maximum parsimony (MP) method frequently allows a number of topologies with a same total branching length. RESULTS: Kitazoe et al. developed multidimensional vector-space representation of phylogeny. It converts additivity of evolutionary distances to orthogonality among the vectors expressing branches, and provides a unified index to measure deviations from the orthogoality. In this paper, this index is used to detect and exclude sequences with large deviations from orthogonality, and then selects a maximum subset ("core set") of sequences for which MP generates a single solution. Once the core set tree is formed whose all the node sequences are given, the excluded sequences are found to have basically two phylogenetic positions on this tree, respectively. Fortunately, since multiple substitutions are rare in intra-species sequences, the variance of nucleotide transitions is confined to a small range. By applying the core set approach to 38 partial env sequences of HIV-1 in a single patient and also 198 mitochondrial COI and COII DNA sequences of Anopheles dirus, we demonstrate how consistently this approach constructs the tree. CONCLUSION: In the HIV dataset, we confirmed that the obtained core set tree is the unique maximum set for which MP proposes a single tree. In the mosquito data set, the fluctuation of nucleotide transitions caused by the sequences excluded from the core set was very small. We reproduced this core-set tree by simulation based on random process, and applied our approach to many sets of the obtained endpoint sequences. Consequently, the ninety percent of the endpoint sequences was identified as the core sets and the obtained node sequences were perfectly identical to the true ones.

Animals↗
PubMed2004

Evidence for two independent lineages of Griffithsia (Ceramiaceae, Rhodophyta) based on plastid protein-coding psaA, psbA, and rbcL gene sequences.

The ceramiaceous red algal genus Griffithsia has characteristic large vegetative cells visible to the unaided eye and thousands of nuclei in a single cell at maturity. Its members often occur intertidally along temperate to tropical coasts. Although previous morphological studies indicated that Griffithsia is subdivided into four groups, there is no molecular phylogeny for the genus. We present the multigene phylogeny of the genus based on plastid protein-coding psaA, psbA, and rbcL genes from ten samples of eight Griffithsia species, eight samples of five putative relatives, such as Anotrichium and Halurus, and three outgroup taxa. Saturation plots for each of the three datasets showed no evidence of saturation at any codon position. The partition homogeneity test indicated that none of the individual datasets resulted in significantly incongruent trees. All the analyses of individual and concatenated datasets separated Griffithsia into two well-defined lineages: Lineage 1 was composed of Griffithsia corallinoides, Griffithsia pacifica, and Griffithsia tomo-yamadae, while lineage 2 encompassed Griffithsia antarctica, Griffithsia japonica, Griffithsia teges, Griffithsia traversii, and Griffithsia sp. Our results support the monophyly of the four Anotrichium species and cast a question on the autonomy of Halurus. The monophyly of the tribe Griffithsieae is well resolved, although interrelationships among Griffithsia, Anotrichium, and Halurus were unclear. Our study indicates that the psaA and psbA genes are powerful new tools for the genus-level phylogeny of red algal groups, such as Griffithsia. This is the first report on the multigene phylogeny of the Ceramiales algae based on three protein-coding plastid genes.

Algal Proteins↗
PubMed2005

An empirical assessment of long-branch attraction artefacts in deep eukaryotic phylogenomics.

In the context of exponential growing molecular databases, it becomes increasingly easy to assemble large multigene data sets for phylogenomic studies. The expected increase of resolution due to the reduction of the sampling (stochastic) error is becoming a reality. However, the impact of systematic biases will also become more apparent or even dominant. We have chosen to study the case of the long-branch attraction artefact (LBA) using real instead of simulated sequences. Two fast-evolving eukaryotic lineages, whose evolutionary positions are well established, microsporidia and the nucleomorph of cryptophytes, were chosen as model species. A large data set was assembled (44 species, 133 genes, and 24,294 amino acid positions) and the resulting rooted eukaryotic phylogeny (using a distant archaeal outgroup) is positively misled by an LBA artefact despite the use of a maximum likelihood-based tree reconstruction method with a complex model of sequence evolution. When the fastest evolving proteins from the fast lineages are progressively removed (up to 90%), the bootstrap support for the apparently artefactual basal placement decreases to virtually 0%, and conversely only the expected placement, among all the possible locations of the fast-evolving species, receives increasing support that eventually converges to 100%. The percentage of removal of the fastest evolving proteins constitutes a reliable estimate of the sensitivity of phylogenetic inference to LBA. This protocol confirms that both a rich species sampling (especially the presence of a species that is closely related to the fast-evolving lineage) and a probabilistic method with a complex model are important to overcome the LBA artefact. Finally, we observed that phylogenetic inference methods perform strikingly better with simulated as opposed to real data, and suggest that testing the reliability of phylogenetic inference methods with simulated data leads to overconfidence in their performance. Although phylogenomic studies can be affected by systematic biases, the possibility of discarding a large amount of data containing most of the nonphylogenetic signal allows recovering a phylogeny that is less affected by systematic biases, while maintaining a high statistical support.

Animals↗
PubMed1999

Phylogeny and evolution of the Drosophila nasuta subgroup based on mitochondrial ND4 and ND4L gene sequences.

The sequences of the mitochondrial ND4 gene (1339 bp) and the ND4L gene (290 bp) were determined for all the 14 extant taxa of the Drosophila nasuta subgroup. The average A + T content of ND4 genes is 76.5% and that of ND4L genes is 83.5%. A total of 114 variable sites were scored. The ND4 gene sequence divergence ranged from 0 to 5.4% within the subgroup. The substitution rate of the ND4 gene is about 1.25% per million years. The base substitution of the genes is strongly transition biased. Neighbor-joining and parsimony were used to construct a phylogeny based on the resultant sequence data set. According to these trees, five distinct mtDNA clades can be identified. D. niveifrons represents the most diverged lineage. D. sulfurigaster bilimbata and D. kepulauana form two independent lineages. The other two clades are the kohkoa complex and the albomicans complex. The kohkoa complex consists of D. sulfurigaster sulfurigaster, D. pulaua, D. kohkoa, and Taxon-F. The albomicans complex can be divided into two groups: D. nasuta, D. sulfurigaster neonasuta, D. sulfurigaster albostrigata, and D. albomicans from Chiangmai form one group; and D. pallidifrons, Taxon-I, Taxon-J, and D. albomicans from China form the other group. High genetic differentiation was found among D. albomicans populations. Based on our phylogenetic results, we hypothesize that D. niveifrons diverged first from the D. nasuta subgroup in Papua New Guinea about 3.5 Mya. The ancestral population spread to the north and when it reached Borneo, it diversified sequentially into the kohkoa complex, D. s. bilimbata, and D. kepulauana. About 1 Mya, another radiation occurred when the ancestral populations reached the Indo-China Peninsula, forming the albomicans complex. Discrepancy between morphological groupings and phylogenetic results suggests that the male morphological traits may not be orthologous.

Animals↗