Prof. Josué Núñez passed away on August 19th 2014 at the age of 89. He was a pioneer in the field of insect physiology and a founder of the study of behavioural physiology in Argentina and other Latin-American countries such as Brazil and Venezuela. Josué was born in 1924, in the city of Tapalqué, a small town in the middle of the province of Buenos Aires, Argentina. After a basic education in the prestigious ''Colegio Nacional de Buenos Aires'', he studied biology at the University of Buenos Aires, where he obtained his PhD in 1953. Throughout his long and fructiferous scientific career, he worked in different reputed laboratories around the world. Thanks to grants from the Alexander-von-Humboldt foundation, he stayed several years in Germany, 1983, after the end of Argentina's worst military dictatorship, he returned to his country, where he was appointed as a Full Professor of the University of Buenos Aires and as a Principal Investigator of the Argentinean National Research Council. During this period of national reconstruction, he played a most significant role for the development of biological studies and the training of young students. He participated actively in the creation of a new curriculum in biological sciences, incorporating several areas of study and research such as Animal Physiology, Behavioral Physiology and Insect Physiology, which were relegated until then. In addition, he founded, together with Hector Maldonado, the first laboratory of Behavioural Physiology, and later the laboratory of Insect Physiology, contributing thereby to the training of several generations of students, many of whom occupy currently chairs and professorships in Argentina and Europe. Josué Núñez retired officially in 1990 but continued his scientific activities in an intensive way thanks to a nomination as a Consultant Professor of the University of Buenos Aires, a position he kept until 2008. In 2007, he was elected as a member of the Buenos Aires Academy of Sciences. Josué Núñez was passionate about insects and made several seminal contributions on insect morphology, physiology and behaviour. His work was extremely inventive and was characterized by the development and successful employ of self-made ingenious tools and experimental devices, such as regulated artificial feeders for honeybees and haematophagous bugs, aimed at quantifying responses in unrestrained, free-behaving insects under controlled conditions. His main study models were precisely blood-sucking bugs and honeybees, and his original contributions underlie the strong ''feeling for the organism'' he had when posing relevant scientific questions. Among his numerous contributions, one can cite the discovery of prothoracic glands and the first experimental evidence of neuro-hormonal control of diuresis in Coleop-tera, the nervous control of both the mechanical properties of the cuticle and the diuretic activity in Rhodnius blood-sucking bugs, the neural regulation of ingestion in dipterans, the use of repellent pheromones during foraging in honeybees, the control of crop-filling in honeybees that led to the hypothesis of a trade-off between individual and colony-wide foraging efficiency, mediated by communication , in social insects, and the perception of infrared radiation in haematophagous bugs, among others. Josué Núñez received several prestigious distinctions from the Argentinean scientific community such as the Konex Prize for science and technology, awarded twice to him, in 1993 and 2003. He himself, however, never regarded these many awards as very important; humility and a devoted commitment to science characterized his style, which was always accompanied by a high dose of sense of humour, something that everyone who had the privilege of working under his direction remembers fondly. Josué exerted a strong influence on his numerous students, to whom he transmitted his passion, curiosity and scientific rigour. He recognized that students and young scientists need to learn to be independent, so he gave them independence. His collaborators will never forget the endless discussions about their ongoing projects, his unorthodox manner, nor the long and intellectually enriching, open-end talks on subjects as eclectic as the beginnings of insect physiology, fractals, complex systems, bio-mimetics, bio-food and eco-engineering, always accompanied by litres of mate, an Argentinean typical infusion. Our sadness over Josué's death is somehow alleviated by the fact that his scientific legacy will enrich us for many generations to come and by the happy memories of the rich years that we were allowed to spend with him.