Project 2622: N. Guil, R. Guidetti, M. Cesari, T. Marchioro, L. Rebecchi, A. Machordom. 2022. Molecular phylogenetics, speciation, and long distance dispersal in tardigrade evolution: A case study of the genus Milnesium. Molecular Phylogenetics and Evolution. 169:107401.
Specimen: Milnesium (unvouchered)
View: M437222 Habitus lateral view. Head lateral view. Lateral view buccopharyngeal apparatus in four different planes. Two planes of claws in PI in lateral view. Two planes of claws in PII in ventrolateral view.

Abstract

Microorganisms (sensu lato, i.e., including micrometazoans) are thought to have cosmopolitan geographic distributions due to their theoretically unlimited dispersal capabilities, a consequence of their tiny size, population dynamics, and resistant forms. However, several molecular studies of microorganisms have identified biogeographic patterns indicating cryptic speciation and/or weak species definitions. Using a multi-locus approach with the genus Milnesium (Tardigrada), we aimed to determine the genetic structure of populations worldwide and the effects of long distance dispersal (LDD) on genetic connectivity and relationships across the six continents. Our results on this micrometazoan's genetic structure and LDD at global and micro-local scales indicate contrasting patterns not easily explained by a unique or simple phenomenon. Overall, we report three key findings: (i) confirmation of long distance dispersal for tardigrades, (ii) populations with globally-shared or endemic micro-local haplotypes, and (iii) a supported genetic structure instead of the homogeneous genetic distribution hypothesized for microorganisms with LDD capabilities. Moreover, incongruences between our morphological and molecular results suggest that species delimitation within the genus Milnesium could be problematic due to homoplasy. Duality found for Milnesium populations at the global scale, namely, a molecular phylogenetic structure mixed with widely distributed haplotypes (but without any apparent biogeographic structure), is similar to patterns observed for some unicellular, prokaryotic and eukaryotic, microorganisms. Factors influencing these patterns are discussed within an evolutionary framework.


Read the article »

Article DOI: 10.1016/j.ympev.2022.107401

Project DOI: 10.7934/P2622, http://dx.doi.org/10.7934/P2622
This project contains
  • 68 Media
  • 2 Taxa
  • 1 Specimen
Total size of project's media files: 157.37M

Download Project SDD File
Currently Viewing:
MorphoBank Project 2622
  • Creation Date:
    21 February 2017
  • Publication Date:
    17 January 2022
  • Project views: 15815

    Authors' Institutions

    • University of Modena and Reggio Emilia

    • Museo Nacional de Ciencias Naturales de Madrid (CSIC)



    Members

    member name taxa specimens media media
    notes
    Noemi Guil
    Project Administrator
    21680


    Project has no matrices defined.



    Project views

    type number of views Individual items viewed (where applicable)
    Total project views15815
    Project overview522
    Media views13351Media search (1003 views); M437224 (245 views); M437222 (262 views); M437223 (194 views); M437225 (196 views); M437226 (183 views); M437227 (186 views); M437228 (179 views); M437229 (253 views); M437287 (150 views); M437250 (247 views); M437266 (188 views); M437283 (156 views); M437276 (152 views); M437230 (187 views); M437231 (236 views); M437232 (189 views); M437233 (192 views); M437234 (185 views); M437235 (239 views); M437236 (184 views); M437237 (193 views); M437238 (184 views); M437239 (183 views); M437240 (194 views); M437241 (177 views); M437242 (189 views); M437243 (184 views); M437244 (182 views); M437245 (187 views); M437246 (175 views); M437247 (244 views); M437272 (159 views); M437284 (162 views); M437286 (139 views); M437279 (150 views); M437262 (190 views); M437271 (143 views); M437259 (188 views); M437275 (151 views); M437268 (187 views); M437289 (149 views); M437267 (176 views); M437263 (179 views); M437290 (148 views); M437260 (181 views); M437257 (201 views); M437265 (173 views); M437255 (186 views); M437258 (181 views); M437285 (158 views); M437269 (170 views); M437253 (180 views); M437280 (150 views); M437270 (174 views); M437274 (144 views); M437288 (138 views); M437249 (190 views); M437248 (199 views); M437278 (146 views); M437251 (172 views); M437256 (184 views); M437277 (145 views); M437282 (145 views); M437281 (170 views); M437273 (143 views); M437252 (238 views); M437261 (179 views); M437264 (185 views);
    Bibliography274
    Specimen list669
    Taxon list384
    Views for media list611
    Documents list4




    Project downloads

    type number of downloads Individual items downloaded (where applicable)
    Total downloads from project13
    Project downloads13