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Molecular phylogeny of Myriapoda provides insights into evolutionary patterns of the mode in post-embryonic development.

Miyazawa H, Ueda C, Yahata K, Su ZH - Sci Rep (2014)

Bottom Line: Here we report the results of phylogenetic analyses and estimations of divergence time and ancestral state of myriapods.The results revealed that Symphyla whose phylogenetic position has long been debated is the sister lineage to all other myriapods, and that the interordinal relationships within classes were consistent with traditional classifications.Ancestral state estimation based on the tree topology suggests that myriapods evolved from an ancestral state that was characterized by a hemianamorphic mode of post-embryonic development and had a relatively low number of body segments and legs.

View Article: PubMed Central - PubMed

Affiliation: 1] Department of Biological Sciences, Graduate School of Science, Osaka University, Osaka 560-0043, Japan [2] JT Biohistory Research Hall, 1-1 Murasaki-cho, Takatsuki, Osaka 569-1125, Japan.

ABSTRACT
Myriapoda, a subphylum of Arthropoda, comprises four classes, Chilopoda, Diplopoda, Pauropoda, and Symphyla. While recent molecular evidence has shown that Myriapoda is monophyletic, the internal phylogeny, which is pivotal for understanding the evolutionary history of myriapods, remains unresolved. Here we report the results of phylogenetic analyses and estimations of divergence time and ancestral state of myriapods. Phylogenetic analyses were performed based on three nuclear protein-coding genes determined from 19 myriapods representing the four classes (17 orders) and 11 outgroup species. The results revealed that Symphyla whose phylogenetic position has long been debated is the sister lineage to all other myriapods, and that the interordinal relationships within classes were consistent with traditional classifications. Ancestral state estimation based on the tree topology suggests that myriapods evolved from an ancestral state that was characterized by a hemianamorphic mode of post-embryonic development and had a relatively low number of body segments and legs.

Show MeSH
Evolutionary transition of post-embryonic development mode.Ancestral state estimation is based on the RAxML topology (Fig. 3) using a likelihood algorithm. Pie charts represent the relative likelihood of different mode of post-embryonic development. The number of body segments of the myriapods belonging to the order is shown in brackets after the order name. The illustrations of the four representative myriapods were drawn by the first author (H.M.) based on the pictures shown in Fig. 1.
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f5: Evolutionary transition of post-embryonic development mode.Ancestral state estimation is based on the RAxML topology (Fig. 3) using a likelihood algorithm. Pie charts represent the relative likelihood of different mode of post-embryonic development. The number of body segments of the myriapods belonging to the order is shown in brackets after the order name. The illustrations of the four representative myriapods were drawn by the first author (H.M.) based on the pictures shown in Fig. 1.

Mentions: Among extant myriapods, post-embryonic development is considered to occur by one of four modes: epimorphosis, euanamorphosis, hemianamorphosis, and teloanamorphosis45. Myriapods employing epimorphic and teloanamorphic modes were clustered into common groups, respectively, whereas myriapods employing the euanamorphic and hemianamorphic modes were separated into different clades (Fig. 5). Ancestral state estimation using Mesquite (a modular system for evolutionary analysis, Version 2.75. [http://mesquiteproject.org]) based on the inferred phylogenetic tree topologies revealed that hemianamorphic mode is the ancestral condition of myriapod post-embryonic development, and that the other modes developed from the hemianamorphic mode (Fig. 5). However, it is possible that the origin of the teloanamorphic mode may be the euanamorphic mode (Fig. 5). The likelihood proportions of the four modes on the nodes of the tree topology are shown in Supplementary Fig. S4.


Molecular phylogeny of Myriapoda provides insights into evolutionary patterns of the mode in post-embryonic development.

Miyazawa H, Ueda C, Yahata K, Su ZH - Sci Rep (2014)

Evolutionary transition of post-embryonic development mode.Ancestral state estimation is based on the RAxML topology (Fig. 3) using a likelihood algorithm. Pie charts represent the relative likelihood of different mode of post-embryonic development. The number of body segments of the myriapods belonging to the order is shown in brackets after the order name. The illustrations of the four representative myriapods were drawn by the first author (H.M.) based on the pictures shown in Fig. 1.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3927213&req=5

f5: Evolutionary transition of post-embryonic development mode.Ancestral state estimation is based on the RAxML topology (Fig. 3) using a likelihood algorithm. Pie charts represent the relative likelihood of different mode of post-embryonic development. The number of body segments of the myriapods belonging to the order is shown in brackets after the order name. The illustrations of the four representative myriapods were drawn by the first author (H.M.) based on the pictures shown in Fig. 1.
Mentions: Among extant myriapods, post-embryonic development is considered to occur by one of four modes: epimorphosis, euanamorphosis, hemianamorphosis, and teloanamorphosis45. Myriapods employing epimorphic and teloanamorphic modes were clustered into common groups, respectively, whereas myriapods employing the euanamorphic and hemianamorphic modes were separated into different clades (Fig. 5). Ancestral state estimation using Mesquite (a modular system for evolutionary analysis, Version 2.75. [http://mesquiteproject.org]) based on the inferred phylogenetic tree topologies revealed that hemianamorphic mode is the ancestral condition of myriapod post-embryonic development, and that the other modes developed from the hemianamorphic mode (Fig. 5). However, it is possible that the origin of the teloanamorphic mode may be the euanamorphic mode (Fig. 5). The likelihood proportions of the four modes on the nodes of the tree topology are shown in Supplementary Fig. S4.

Bottom Line: Here we report the results of phylogenetic analyses and estimations of divergence time and ancestral state of myriapods.The results revealed that Symphyla whose phylogenetic position has long been debated is the sister lineage to all other myriapods, and that the interordinal relationships within classes were consistent with traditional classifications.Ancestral state estimation based on the tree topology suggests that myriapods evolved from an ancestral state that was characterized by a hemianamorphic mode of post-embryonic development and had a relatively low number of body segments and legs.

View Article: PubMed Central - PubMed

Affiliation: 1] Department of Biological Sciences, Graduate School of Science, Osaka University, Osaka 560-0043, Japan [2] JT Biohistory Research Hall, 1-1 Murasaki-cho, Takatsuki, Osaka 569-1125, Japan.

ABSTRACT
Myriapoda, a subphylum of Arthropoda, comprises four classes, Chilopoda, Diplopoda, Pauropoda, and Symphyla. While recent molecular evidence has shown that Myriapoda is monophyletic, the internal phylogeny, which is pivotal for understanding the evolutionary history of myriapods, remains unresolved. Here we report the results of phylogenetic analyses and estimations of divergence time and ancestral state of myriapods. Phylogenetic analyses were performed based on three nuclear protein-coding genes determined from 19 myriapods representing the four classes (17 orders) and 11 outgroup species. The results revealed that Symphyla whose phylogenetic position has long been debated is the sister lineage to all other myriapods, and that the interordinal relationships within classes were consistent with traditional classifications. Ancestral state estimation based on the tree topology suggests that myriapods evolved from an ancestral state that was characterized by a hemianamorphic mode of post-embryonic development and had a relatively low number of body segments and legs.

Show MeSH