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Apidologie

, Volume 39, Issue 1, pp 3–15 | Cite as

Phylogenetics of allodapine bees: a review of social evolution, parasitism and biogeography

  • Simon M. Tierney
  • Jaclyn A. Smith
  • Luke Chenoweth
  • Michael P. Schwarz
Review Article

Abstract

It has been assumed that allodapine bees represent early stages in the evolution of social behaviour. Early studies suggested that sociality evolved from solitary forms, and that the solitary to social transition coincided with a transition from mass to progressive provisioning of brood. Recent studies challenge both of these assumptions, they suggest that: (i) Macrogalea replaces Halterapis + Compsomelissa as the sister group to all other genera; (ii) sociality is plesiomorphic for the tribe; and based on extended Halterapis research, (iii) there are no strictly solitary allodapine species and, therefore, no reversals to solitary living. Penalised likelihood dating of Bayesian inferred phylograms show allodapine lineages have an origin older than 40 Mya. The early origin of sociality in this tribe may explain the diverse array of social organization (and social parasitism) found in species across a range of clades, and the age of the group raises curious biogeographic scenarios.

social evolution phylogenetics alloparental care brood provisioning allodapine bees 

Phylogénétique des abeilles de la tribu des Allodapini (Apidae, Xylocopinae): le point sur l’évolution sociale, le parasitisme et la biogéographie

Allodapini abeille évolution sociale phylogénétique soin alloparental approvisionnement du couvain 

Phylogenetik allodapiner Bienen: ein Review über soziale Evolution, Parasitismus und Biogeographie

Zusammenfassung

Einige Bienen und Wespen sind fakultativ sozial. Anders als Honigbienen, Ameisen und Termiten sind ihre reproduktiven Rollen nicht durch morphologische Kasten eingeschränkt. Alle Weibchen sind daher in der Lage ihre eigene Brut unabhängig aufzuziehen. Daher ist die entstehende Gruppendynamik (soziale Organisation) hoch flexibel und reicht von der solitären Lebensweise bis zu hochorganisierten (eusozialen) Gemeinwesen, wobei diese Unterschiede sowohl innerhalb einer Art als auch zwischen nahverwandten Arten auftreten.

Aus diesem Grund sind solche Organismen sehr gut für vergleichende Untersuchungen über altruistisches Verhalten und dessen Entstehung geeignet. Warum sollte ein Individuum die Gelegenheit zu eigener Reproduktion auslassen und anstelle dessen anderen helfen, deren Brut großzuziehen? Die fakultativ sozialen allodapinen Bienen ziehen ihre Brut in offenen linearen Stengelsystemen auf (i.e. nicht in von der äußeren Umgebung abgeschirmten Brutzellen), dies erzeugt unter sozialen Insekten einzigartige Lebensgeschichten und haben sie über die vergangenen mehr als 40 Jahre zu einem wichtigen Modellsystem gemacht.

Vergleichende evolutionäre Forschung benötigt einen gesicherten Stammbaum (einen Baum der evolutionären Geschichte, der die Abstammungslinien sichtbar macht), aus dem dann die Entwicklung eines spezifischen Charakteristikums hergeleitet werden kann. Anfängliche Versuche, die Phylogenie der Allodapinen aufzulösen waren problematisch, vor allem da unabhängige auf Eigenschaften der Larven, Puppen oder Adulten beruhende Studien zu widersprüchlichen Ergebnissen geführt hatten. Analysen von DNA Sequenzen unterstützen eine sehr unterschiedliche Phylogenie, die zu einer Umordnung der Beziehungen zwischen den Gattungen führt. Das hauptsächliche Ergebnis ist, dass alle Gattungen sozial sind. Es widerspricht damit früheren Interpretationen, nach denen die soziale Evolution innerhalb der noch bestehenden Linien eingesetzt hat. Die Sozialität entwickelte sich eindeutig vor den heute lebenden Arten des Stammes zurück.

Anhand von baltischen Bernsteinfossilien eines ausgestorbenen Geschwisterstammes haben die Untersucher die Zeiträume der Entstehung dieser Bienen und ihrer Auseinanderentwicklung sowie des Bestehens ihrer sozialen Organisation einzuschätzen versucht. Nach diesen Analysen ist der Tribus vor etwa 39–80 Millionen Jahren entstanden, obwohl diese Schätzungen zurückhaltend sind und die tatsächliche Entstehungszeit vermutlich etwas früher war. Dies legt nahe, dass die Art des in dem Tribus gezeigten Sozialverhaltens keineswegs primitiv ist. Soziales Verhalten tritt in allen größeren phylogenetischen Abzweigungen auf und ist mit einer hochgradig zur weiblichen Seite neigenden Geschlechtszuweisung verbunden — eine von der Verwandtenselektion, der dominanten Theorie der letzten 30 Jahre zur Entstehung altruistischen Verhaltens nahegelegten Schlüsselgröße. Eine datierte Phylogenie ermöglicht darüber hinaus eine Untersuchung der biogeographischen Theorie. Die hier zusammengefassten Ergebnisse ergeben überraschende Einsichten über die Verbreitungsfähigkeit dieser Bienen als auch über die Rolle der nun überfluteten Landmassen im biotischen Austausch zwischen Madagaskar, Antarktis, und zuletzt auch Australien.

Sozialevolution Phylogenetik Alloparentale Pflege Brutversorgung Allodapine Bienen 

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Copyright information

© Springer S+B Media B.V. 2008

Authors and Affiliations

  • Simon M. Tierney
    • 1
    • 2
  • Jaclyn A. Smith
    • 1
  • Luke Chenoweth
    • 1
  • Michael P. Schwarz
    • 1
  1. 1.School of Biological SciencesFlinders UniversityAdelaideAustralia
  2. 2.Smithsonian Tropical Research InstituteBalboaRepublic of Panama

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