TY - JOUR T1 - Radiations and key innovations in an early branching angiosperm lineage (Annonaceae; Magnoliales) JF - Botanical Journal of the Linnean SocietyBotanical Journal of the Linnean Society Y1 - 2012 A1 - Erkens, Roy H. J. A1 - Chatrou, Lars W. A1 - Couvreur, Thomas L. P. SP - 117 EP - 134 KW - adaptive radiation KW - rate shift KW - sister-group comparison KW - stochastic branching pattern KW - temporal method KW - topological method AB - Biologists are fascinated by species-rich groups and have attempted to discover the causes for their abundant diversification. Comprehension of the causes and mechanisms underpinning radiations and detection of their frequency will contribute greatly to the understanding of the evolutionary origin of biodiversity and its ecological structure. A dated and well-resolved phylogenetic tree of Annonaceae was used to study diversification patterns in the family in order to identify factors that drive speciation and the evolution of morphological (key) characters. It was found that, except for Goniothalamus, the largest genera in the family are not the result of radiations. Furthermore, the difference in species numbers between subfamilies Annonoideae (former long branch clade) and Malmeoideae (former short branch clade) cannot be attributed to significant differences in the diversification rate. Most of the speciation in Annonaceae is not distinguishable from a random branching process (i.e. chance), and no special explanations are therefore necessary for the distribution of species richness across the major part of the phylogenetic tree for Annonaceae. Only for a small number of clades can key innovations be invoked to explain the elevated rate of diversification. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 169, 117–134. PB - Blackwell Publishing Ltd VL - 169 SN - 1095-8339 JO - Bot J Linn Soc ER - TY - JOUR T1 - Radiations and key innovations in an early branching angiosperm lineage (Annonaceae; Magnoliales) JF - Botanical Journal of the Linnean Society Y1 - 2012 A1 - Erkens, Roy H. J. A1 - Chatrou, Lars W. A1 - Couvreur, Thomas L.P. SP - 117 EP - 134 KW - adaptive radiation KW - rate shift KW - sister-group comparison KW - stochastic branching pattern KW - temporal method KW - topological method AB -

Biologists are fascinated by species-rich groups and have attempted to discover the causes for their abundant diversification. Comprehension of the causes and mechanisms underpinning radiations and detection of their frequency will contribute greatly to the understanding of the evolutionary origin of biodiversity and its ecological structure. A dated and well-resolved phylogenetic tree of Annonaceae was used to study diversification patterns in the family in order to identify factors that drive speciation and the evolution of morphological (key) characters. It was found that, except for Goniothalamus, the largest genera in the family are not the result of radiations. Furthermore, the difference in species numbers between subfamilies Annonoideae (former long branch clade) and Malmeoideae (former short branch clade) cannot be attributed to significant differences in the diversification rate. Most of the speciation in Annonaceae is not distinguishable from a random branching process (i.e. chance), and no special explanations are therefore necessary for the distribution of species richness across the major part of the phylogenetic tree for Annonaceae. Only for a small number of clades can key innovations be invoked to explain the elevated rate of diversification. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 169, 117–134.

PB - Blackwell Publishing Ltd VL - 169 SN - 1095-8339 UR - http://dx.doi.org/10.1111/j.1095-8339.2012.01223.x ER -