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Life history evolution

Marine invertebrates are characterized by a rich array of life history strategies; some species are direct-developers, like most developmental model species, where the adult body plan emerges straight from the embryo. However, most marine invertebrates have a distinct larval body plan that only develops features of the adult body plan late in larval development, often months following embryogenesis.

Enteropneust hemichordate worms have both direct and indirect-developing species, and we work on both types of development in the lab. Schizocardium californicum is a local CA species that has distinct larval and adult body plans. The larvae develop for several months in the plankton transforming into an adult in a rapid and radical transition that last 24- 48hrs. We are investigating the transition of metamorphosis between the larval and adult body plan at the cellular level to investigate how such rapid reorganization occurs. 

We are taking a genomic approach to investigate how this dramatic transformation takes place and how cellular composition changes through metamorphosis. A collaboration with Pacific Biosciences and Dan Rohksar's lab at UC Berkeley has delivered a very high-quality genome assembly. This high-quality resource then made it possible to partner with the CZ Biohub through their intercampus award program to use a single cell RNAseq approach to determine how the cellular composition of the larval body plan changes through the process of metamorphosis. This has provided a unique perspective how a single genome regulates the formation of two distinct body plans. This work has been a highly collaborative effort and we are grateful to have partnered to do the analysis with Blair Benham-Pyle and Carolyn Brewster in Alejandro Sánchez Alvarado’s lab.


Relevant Publications:

Formery, L., Lowe C.J. (2023) Integrating Complex Life Cycles in Comparative Developmental Biology. Annual Review of Genetics, 57.

Gonzalez P, Uhlinger KR, Lowe CJ. (2017) The adult body plan of indirect developing hemichordates develops by adding a hox-patterned trunk to an anterior larval territory. Current biology, 27(1), 87-95. DOI:10.1016/j.cub.2016.10.047