Convergence on a growth habit through diverse morphologies.

What is a geophyte?

Geophytes are terrestrial plants with their growing points located below ground on structures such as a bulb, corm, tuber and/or rhizome. Examples you might be familiar with include potato, onion, turmeric, and taro. The many forms that belowground bud placement has taken is the result of evolution in response to various stimuli like fires, herbivores, droughts, and freezing temperatures. Additionally, some lineages appear to “favor” evolving one trait over another. For example, bulbs are found throughout the monocots, but are almost absent in all other plant lineages (excluding Oxalis). Therefore, in addition to abiotic and biotic interactions, anatomy and morphology are likely significant contributors to belowground trait evolution as well.

Unfortunately, the complex evolution of belowground bud placement remains obscured due to a lack of studies on belowground trait morphology as well as ambiguous or incorrect trait classification. By not including the belowground aspects of plants into studies on their evolution and ecology, we are undoubtedly missing a critical piece of the puzzle. My research focuses on obtaining a holistic understanding of the evolution of the geophytic habit across plants using museum and living specimens, experimental manipulations, and phylogenetics.

To promote collaborative research on geophytes, I founded an international working group called GOOPhy (Geophytic Organisms – Ontology & Phylogeny]) (www.geophytes.com), whose goals are understanding the relationship between plant form and function with a special focus on, you guessed it, GEOPHYTES!

Relevant Publications

Tribble CM, Martinez-Gomez J, Howard CC, Males J, Sosa V, Sessa EB, Cellinese N, Specht CD. 2021. Get the shovel: morphological and evolutionary complexities of belowground organs in geophytes. American Journal of Botany. https://doi.org/10.1002/ajb2.1623

Howard CC, Landis JB, Beaulieu JM, Cellinese N. 2020. Geophytism in the monocots leads to higher rates of diversification. New Phytologist. https://doi.org/10.1111/nph.16155

Howard CC, Folk RA, Beaulieu JM, Cellinese N. 2019. The monocotyledonous underground: global climatic and phylogenetic patterns of geophyte diversity. American Journal of Botany. https://doi.org/10.1002/ajb2.1289