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Review article - Peer-reviewed, 2022

Taste and Smell: A Unifying Chemosensory Theory

Mollo, Ernesto; Boero, Ferdinando; Penuelas, Josep; Fontana, Angelo; Garson, Mary J.; Roussis, Vassilios; Cerrano, Carlo; Polese, Gianluca; Cattaneo, Alberto Maria; Mudianta, I Wayan; Genta-Jouve, Gregory; Taglialatela-Scafati, Orazio; Appendino, Giovanni; Amodeo, Pietro; Ghiselin, Michael T.


Since antiquity, the sense of smell (olfaction) is considered as a distance sense, just like sight and hearing. Conversely, the sense of taste (gustation) is thought to operate by direct contact, similarly to touch. With the progress of natural sciences, information at molecular, anatomical, and neurobiological levels has also contributed to the taste-smell dichotomy, but much evidence inconsistent with a sharp differentiation of these two senses has emerged, especially when considering species other than humans. In spite of this, conflicting information has been interpreted so that it could conform to the traditional differentiation. As a result, a confirmation bias is currently affecting scientific research on chemosensory systems and is also hindering the development of a satisfactory narrative of the evolution of chemical communication across taxa. From this perspective, the chemosensory dichotomy loses its validity and usefulness. We thus propose the unification of all chemosensory modalities into a single sense, moving toward a synthetic, complex, and interconnected perspective on the gradual processes by which a vast variety of chemicals have become signals that are crucially important to communication among and within cells, organs, and organisms in a wide variety of environmental conditions.


chemical senses; receptors; ligands; chemosensory systems; evolution of chemosensation; chemical ecology

Published in

Quarterly Review of Biology
2022, volume: 97, number: 2, pages: 69-94

Authors' information

Mollo, Ernesto
National Research Council (CNR)
Boero, Ferdinando
National Research Council (CNR)
Penuelas, Josep
Consejo Superior de Investigaciones Cientificas (CSIC)
Fontana, Angelo
National Research Council (CNR)
Garson, Mary J.
University of Queensland
Roussis, Vassilios
National and Kapodistrian University of Athens
Cerrano, Carlo
Marche Polytechnic University
Polese, Gianluca
University of Naples Federico II
University of Lausanne
Swedish University of Agricultural Sciences, Department of Plant Protection Biology
Mudianta, I Wayan
Ganesha University of Education
Genta-Jouve, Gregory
The National Center for Scientific Research (CNRS)
Taglialatela-Scafati, Orazio
University of Naples Federico II
Appendino, Giovanni
University of Eastern Piedmont Amedeo Avogadro
Amodeo, Pietro
National Research Council (CNR)
Ghiselin, Michael T.
California Academy of Sciences

UKÄ Subject classification

Biochemistry and Molecular Biology

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