Abstract Detail

Paleobotany

Evolutionary and ecological influences on monocot leaf venation patterns.

Leaves are instrumental for plants to flourish in environments as they play critical roles in water and gas exchange. As such different leaf traits are informative about controls on plant morphology. One leaf trait, vein density, or vein length per area (VLA), is important as it is directly correlated to photosynthetic rate, hydraulic conductance, and overall gas exchange. Although much is known about VLA trait distribution and disparity in woody angiosperms, less attention has been paid to monocots and to what extent monocot VLA is shaped by ecology and phylogenetic history. The aim of this study was to test: (1) phylogenetic and ecological influences on VLA in monocots and (2) if the eudicot global leaf venation and size scaling relationship holds true for monocots. We analyzed leaves of 814 monocot species (54 families, 10 orders) for VLA and leaf area, and compiled habit and habitat information from the literature. Our data suggest that closely related monocot species do not share similar values of VLA, both among orders and all monocots, and thus there is little phylogenetic influence on VLA. Ecological constraints appeared to have greater influences on VLA with high VLA in larger plants and low VLA in precipitation rich environments. Lastly, our results show that all types of monocot VLA are independent of leaf size, which directly opposes the global leaf vein scaling in eudicots. Our study results indicate that monocot venation patterns are unique to the group, possibly reflecting different ontogenetic and evolutionary pathways in leaf evolution.

1 - University Of Michigan Ann Arbor, Earth And Environmental Science, 2534 North University Building, Michigan, MI, 48109, United States
2 - Department Of Earth & Environmental Sciences, 1100 North University Avenue, Room 2534, NUB, Ann Arbor, MI, 48109, United States

Keywords:
paleobotany
vein density
VLA
monocot.

Presentation Type: Oral Paper
Number: PB2002
Abstract ID:631
Candidate for Awards:Isabel Cookson Award,Maynard F. Moseley Award