title: Global patterns of insect diversification: towards a reconciliation of fossil and molecular evidence?
abstract: Macroevolutionary studies of insects at diverse taxonomic scales often reveal dynamic evolutionary patterns, with multiple inferred diversification rate shifts. Responses to major past environmental changes, such as the Cretaceous Terrestrial Revolution, or the development of major key innovations, such as wings or complete metamorphosis are usually invoked as potential evolutionary triggers. However this view is partially contradicted by studies on the family-level fossil record showing that insect diversification was relatively constant through time. In an attempt to reconcile both views, we investigate large-scale insect diversification dynamics at family level using two distinct types of diversification analyses on a molecular timetree representing ca. 82% of the extant families, and reassess the insect fossil diversity using up-to-date records. Analyses focusing on the fossil record recovered an early burst of diversification, declining to low and steady rates through time, interrupted by extinction events. Phylogenetic analyses showed that major shifts of diversification rates only occurred in the four richest holometabolous orders. Both suggest that neither the development of flight or complete metamorphosis nor the Cretaceous Terrestrial Revolution environmental changes induced immediate changes in diversification regimes; instead clade-specific innovations likely promoted the diversification of major insect orders.
authors.affiliation: CNRS, UMR 5554 Institut des Sciences de l'Evolution (Université de Montpellier), Place Eugène Bataillon, 34095 Montpellier, France.|University of Alberta, Department of Biological Sciences, Edmonton T6G 2E9, AB, Canada.
authors.forename: Fabien L
authors.initials: FL
authors.lastname: Condamine
authors.affiliation: Department of Earth and Planetary Sciences, University of California, Santa Cruz, CA 95064, USA.
authors.forename: Matthew E
authors.initials: ME
authors.lastname: Clapham
authors.affiliation: INRA, UMR 1062 CBGP (INRA, IRD, CIRAD, Montpellier SupAgro), 755 Avenue du Campus Agropolis, 34988 Montferrier-sur-Lez, France.
authors.forename: Gael J
authors.initials: GJ
authors.lastname: Kergoat
mesh_terms: D000818:Animals; D044822:Biodiversity; D005075:Biological Evolution; D002965:Classification; D053476:Extinction, Biological; D005580:Fossils; D007313:Insecta / Q000235:genetics* / Q000502:physiology; D008675:Metamorphosis, Biological; D010802:Phylogeny; D014921:Wings, Animal / Q000502:physiology