... retrieval over time, when compared with the first visits. Even when trained in a go/no-go paradigm which precludes side bias development, ants failed to learn to avoid a pheromone trail. These results show rapid learning flexibility towards an innate social signal, but also demonstrate a rarely seen hard...

... of an elaborate gestural courtship display in a tropical bird, the golden-collared manakin. Skeletal muscle Electromyography Courtship behavior Social signal Biomechanics Golden-collared manakin Spectacular acrobatics and dance are not exclusive to humans. Rather, decades of research show...

... serotonergic system and the hypothalamic—pituitary—interrenal axis. These results support the suggestion that skin darkening in subordinates acts as a social signal announcing social submission. * Author for correspondence (e-mail: [email protected] ) 23 5 2002 © The Company...