John Voorheis Sibole (Enumclaw, State of Washington, United States of America, 1962) is an Assistant Professor Doctor Contracted Substitute of the Departament de Filologia Espanyola, Moderna i Clàssica de Universitat de les Illes Balears (UIB). Graduated with a Bachelor’s degree in Plant Science, Plant Pathology Option  (1987) from the University of California at Davis and received a Doctorate in Biology (2001, Excellent Cum Laude and awarded the Extraordinary Thesis Prize) from the Universitat Autònoma de Barcelona, Bellaterra, with the thesis dissertation: ‘Effects of salt stress in two species of Medicago: the physiological responses'. He was also awarded a Bachelor’s degree in English Studies by the Universitat de les Illes Balears (UIB).

He has taught English as a foreign language and English for special purposes for more than sixteen years.

His research has focused on the adaptations of superior vascular plants to environmental stresses and pathogens (salinity, Magnaporthe ssp. Xillela sp.). He has participated in Spanish national and International projects and is the author of more than a dozen articles, amongst which have been published in the International journals: Plant Science, Planta, and  Physiologia Plantarum.

In 1992 he was awarded the Research Prize by the City of Palma, Mallorca for his research of a prairie in Corral de les Cabres, Majorca that was exposed to saline conditions.