title: Taller plants have lower rates of molecular evolution.
abstract: Rates of molecular evolution have a central role in our understanding of many aspects of species' biology. However, the causes of variation in rates of molecular evolution remain poorly understood, particularly in plants. Here we show that height accounts for about one-fifth of the among-lineage rate variation in the chloroplast and nuclear genomes of plants. This relationship holds across 138 families of flowering plants, and when accounting for variation in species richness, temperature, ultraviolet radiation, latitude and growth form. Our observations can be explained by a link between height and rates of genome copying in plants, and we propose a mechanistic hypothesis to account for this-the 'rate of mitosis' hypothesis. This hypothesis has the potential to explain many disparate observations about rates of molecular evolution across the tree of life. Our results have implications for understanding the evolutionary history and future of plant lineages in a changing world.
authors.affiliation: Ecology, Evolution, and Genetics, Research School of Biology, Building 116 Daley Road, Australian National University, Canberra, Australian Capital Territory 0200, Australia. rob.lanfear@anu.edu.au
authors.forename: Robert
authors.initials: R
authors.lastname: Lanfear
authors.forename: Simon Y W
authors.initials: SY
authors.lastname: Ho
authors.forename: T
authors.initials: T
authors.lastname: Jonathan Davies
authors.forename: Angela T
authors.initials: AT
authors.lastname: Moles
authors.forename: Lonnie
authors.initials: L
authors.lastname: Aarssen
authors.forename: Nathan G
authors.initials: NG
authors.lastname: Swenson
authors.forename: Laura
authors.initials: L
authors.lastname: Warman
authors.forename: Amy E
authors.initials: AE
authors.lastname: Zanne
authors.forename: Andrew P
authors.initials: AP
authors.lastname: Allen
mesh_terms: D019943:Amino Acid Substitution / Q000235:genetics; D002467:Cell Nucleus / Q000235:genetics; D002736:Chloroplasts / Q000235:genetics; D030541:Databases, Genetic; D019143:Evolution, Molecular; D016018:Least-Squares Analysis; D019684:Magnoliopsida / Q000033:anatomy & histology / Q000235:genetics; D010802:Phylogeny; D010944:Plants / Q000033:anatomy & histology* / Q000235:genetics*; D012335:RNA, Ribosomal / Q000235:genetics; D012044:Regression Analysis; D014934:Wood / Q000033:anatomy & histology
chemical_list: D012335:RNA, Ribosomal