When do children start to become aware of the relationship between animal and plant life? According to a study by the UPV/EHU, they begin to associate animals and plants with each other spontaneously in their drawings by the age of eight. The UPV/EHU researchers José Domingo Villarroel, Álvaro Antón, Teresa Nuño and Daniel Zuazagoitia are the authors of this work, published in the scientific journal Sustainability.