Our Research
Evolution of animal cell types
Cell types are the building blocks of multicellular life. Yet how do new cell types evolve and diversify their functions, and how do cell types assemble to form different tissues? Our group works to uncover the ancient history of animal cells by surveying cell types and tissue organization across the tree of life using single-cell sequencing and spatial transcriptomics of whole organisms. We also develop computational tools to link cells across species, reconstruct their evolutionary diversification, and discover novel functional machinery.
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Origin of the nervous system
Our central nervous system contains an estimated 86 million neurons, which are essential for coordinating our body’s functions. Yet the first multicellular animals existed without a nervous system, only later evolving a radial nerve net and then finally a centralized nervous system. Our lab pieces together the history of this transition, investigating synaptic machinery in nerveless sponges with functional proteomics, and the organization of nerve nets in sea anemones using 4D imaging. Our goal is to understand how multicellular animals solved the ability to coordinate cellular behaviors without a nervous system, and how these systems were upgraded to produce the first complex animal behaviors and cognition.
The origin and evolution of cell types. Arendt et al. (2016)
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Evo-devo of sponges, cnidarians, and ctenophores
Our most distant relatives are also our most distinct. Unlike traditional animal models, they have relatively few cell types and build transparent bodies to inhabit the ocean depths. These unique features make them ideal for investigating the rules of animal organization. From molecules to tissues and animal behavior, our group investigates the organizational principles of an entire animal, and how this organization arose at the beginning of animal life.
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Evolution of neuronal types and families. Arendt et al. (2019)
