Abstract Detail

Paleobotany

Atkinson, Brian [1].

Fossil tip-dating in the dogwood order, Cornales.

The dogwood order, Cornales (~605 spp.), is the earliest diverging asterid lineage and the most recent node dating analyses suggest that it experienced an ancient and rapid diversification during the Late Cretaceous. This initial radiation has made it difficult to decipher the early evolution of the group, particularly at deep nodes. However, there have been many recent discoveries of Late Cretaceous cornaleans, which have shed much light on the initial diversification of the order. Phylogenetic analyses based on fruit morphological data have indicated that these and other fossils have a meaningful impact for inferring evolutionary relationships and macroevolutionary patterns. In this study, morphological data from extinct and extant species are integrated with molecular data to further reconstruct the early evolution of Cornales. The concatenated matrix consists of six chloroplast genes, 26s nuclear DNA data, and a fruit morphological matrix of 71 characters. Phylogenetic analyses were conducted within maximum likelihood and Bayesian frameworks. Furthermore, to better understand the timing of cornalean evolution, a total evidence tip dating analysis was conducted using the Fossilized Birth Death process. Preliminary analyses recovered novel deep node relationships and indicate that Late Cretaceous cornaleans are crown members positioned towards deeper nodes. The order is estimated to have diverged at 117 Ma, which supports an Early Cretaceous origin for the asterids and suggests that the initial diversification of eudicots was rapid.

1 - University Of Kansas, Ecology And Evolutionary Biology, 1200 Sunnyside Avenue, 2041 Haworth Hall, Lawrence, KS, 66045, United States

Keywords:
fruits
fossils
Cretaceous
total evidence phylogeny
Tip-dating.

Presentation Type: Oral Paper
Session: PAL3, Paleobotany III: Mesozoic Paleobotany
Location: Tucson C/Starr Pass
Date: Tuesday, July 30th, 2019
Time: 2:45 PM
Number: PAL3006
Abstract ID:627
Candidate for Awards:None