Evolution of Tree Design: Vascular Cambium Mechanics, Wood Parameters, Growth, and Architecture/Biomechanics of Earliest Trees

Virginia Polytechnic Institute And State University, Blacksburg VA

Investigators

Abstract

This project will reconstruct the growth and characteristics of woody support tissues of the first trees and shrubs that grew when early plants colonized the land in the Devonian (400-345 million years ago). The earliest plants lacked the roots, stems, branches, and leaves that are now found in modern plants. But by Mid to Late Devonian times, some plants had these features, and a few had developed growth capabilities and woody tissues that could support tall shrubs and trees. These first trees enjoyed considerable advantages by virtue of their height and spread, such as greater success of spore and seed dispersal and better competition for light and habitat space. The investigators will study cell patterns of fossil woods, stems, and roots to reconstruct the growth and mechanical features of these first woody plants. Additionally, the fine-scale anatomical information obtained in this study will contribute to our knowledge of which plant groups (fossil and modern) are most closely related. The ability to produce wood appears to have evolved several times. This study will resolve questions of the universality of plant construction design, specifically elucidating which common traits are necessary to attain a tree growth form and which are the result of a species' family history and are thus evolutionarily informative.