Create your own conference schedule! Click here for full instructions

Abstract Detail



Pacific Biogeography

Potter, Benjamin [1], Lowry, Porter [2], Munzinger , Jérôme  [3], Gemmill, Chrissen [4].

Biogeography of insular Pacific Pittosporum (Pittosporaceae) revisited.

The genus Pittosporum (Pittosporaceae, Apiales) consists of ca. 150 species of trees, shrubs and lianas. Distribution is throughout the Old World, with centres of species richness in Australia, Hawaii, New Caledonia and New Zealand. Here, we investigated the phylogeny and biogeography of the group using a combination of nuclear ribosomal and chloroplast DNA markers. A nrITS dataset was first assembled sampling ca. 100 species, and based on a preliminary phylogeny of this data a subset of 60 species was selected for additional chloroplast sequencing. This multigene matrix was then used for Bayesian molecular dating and ancestral area analyses. The results suggest the genus has radiated relatively recently, with crown group Pittosporum diversification beginning in the Late Miocene. In congruence with previous studies this was estimated to have occurred in Australia, with subsequent dispersal events taking place to the Pacific and Southeast Asia (Gemmill et al., 2002; Chandler et al., 2007). Our analyses estimate that extant Pittosporum in both New Caledonia and Hawaii are the result of a single colonisation event, but interestingly the 24 species in New Zealand appear to be the result of at least two (but possibly three) independent colonisation events. These results will be discussed and contrasted with those produced using alternative calibration schemes, molecular clock models and sampling densities.


Log in to add this item to your schedule

1 - University of Auckland, School of Biological Sciences, 3a Symonds Street, Auckland, 1010, NZ
2 - Missouri Botanical Garden, Africa and Madagascar Department, P.O. Box 299, St. Louis, MO, 63166-0299, USA
3 - Institut de Recherche pour le Développement (IRD), UMR Botanique et Bioinformatique de l’Architecture des Plantes (AMAP), Laboratoire de Botanique et d’Ecologie Végétale Appliquées, Nouméa, New Caledonia, New Caledonia
4 - Dept Of Biological Sciences, Private Bag 3105, Hamilton, New Zealand

Keywords:
Apiales
Biogeography
molecular dating
Pacific
phylogeny
Pittosporum.

Presentation Type: Colloquium Presentations
Session: C12, Pacific biogeography
Location: 103/Mayo Civic Center
Date: Wednesday, July 25th, 2018
Time: 2:45 PM
Number: C12005
Abstract ID:1212
Candidate for Awards:None


Copyright © 2000-2018, Botanical Society of America. All rights reserved