We know that some plants, especially non-flowering ones, evolved rapidly during the Meso­zoic Era. Ginkgos, for example, first appeared 150 million years ago and became common in the Mesozoic Era. One species, Ginkgo biloba, has been described as a “living fossil.” Certain characteristics enabled early plants to invade and become established on land. Internal ves­sels called vascular tissue circulated nutrients and water to all parts of the plant. An outer layer of waxy cuticle developed to prevent dehydration, and stomata located on the un­dersurfaces of leaves regulate respiration. Roots provide anchorage, nutrient uptake, and general interaction with the chemical/microbial systems in the soil (e. g., the rhizosphere).

New work to redirect the evolutionarily imposed protection of plants’ cell wall polysac­charides is now underway. The objective of “bioenergy plant engineering” is to use genetic tools to modify cell wall characteristics, thus permitting more-efficient chemical and en­zymatic hydrolysis processes, as well as enhanced agronomic productivity. This work will proceed phenomenologically at first — for example, mapping plant quantitative trait loci to beneficial conversion traits. However, this field will mature to a deeper understanding of the processes of cell wall synthesis and assembly, as well as enzymatic deconstruction. Eventually, these biological systems will be sufficiently understood to permit overall system engineer­ing, optimizing both cell wall production and deconstruction in ways not achievable in nature.