Journal
AMERICAN JOURNAL OF BOTANY
Volume 104, Issue 10, Pages 1581-1595Publisher
WILEY
DOI: 10.3732/ajb.1700291
Keywords
Fagaceae; hybridization; Lobatae; Quercus; RAD-seq; red oaks; restriction-site-associated DNA sequencing; systematics
Categories
Funding
- NSF [1146488, 1146102, 1146380]
- Morton Arboretum Center for Tree Science
- Duke University Arts & Sciences Council
- Direct For Biological Sciences
- Division Of Environmental Biology [1146102, 1146380] Funding Source: National Science Foundation
Ask authors/readers for more resources
PREMISE OF THE STUDY: The California Floristic Province (CA-FP) is a unique and diverse region of floral endemism, yet the timing and nature of divergence and diversification of many lineages remain underexplored. We seek to elucidate the evolutionary history of the red oaks of the CA-FP, the Agrifoliae. METHODS: We collected PstI-associated RAD-seq data as well as morphometrics from individuals of the four species across their ranges, including varieties and hybrids. Phylogeny and divergence times were estimated. We analyzed morphological differentiation in over 70 plants using PCA and assessed species delimitation and admixture using genotype clustering analysis in over 40 plants. KEY RESULTS: We find that the Agrifoliae are monophyletic and sister to all other red oak species. Within the Agrifoliae, all species are supported, with Quercus kelloggii sister to a clade of subevergreen taxa: (Quercus agrifolia-(Q. parvula + Q. wislizeni)). Molecular and morphometric analyses are equivocal for named varieties. Notably, Q. parvula var. tamalpaisensis appears to be part of a hybrid swarm between Q. parvula and Q. wislizeni. Dating estimates were concordant with previous hypotheses and geological evidence, with diversification occurring between 10 and 20 million years ago. CONCLUSIONS: The Agrifoliae represent a geographically discrete, early-diverging red oak lineage that diversified during the period of drying and warming associated with Sierran uplift during the middle Miocene. Molecular differentiation within the clade supports the current taxonomy, including an east-west species level pattern (Q. parvula and Q. wislizeni) and north-south intraspecific patterns to some degree, although the latter require additional study.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available