Daniela Rößler
Universität of Bonn, Bonn Institute for Organismic Biology (BIOB), Section II: Animal Diversity, & Max Planck Institute of Animal Behavior, Konstanz
Germany
Spider sleep – what we know and what we still dream of
Much remains unknown about the diversity and evolution of sleep in invertebrates. Recent findings reveal compelling evidence for REM sleep–like behaviors in jumping spiders, including retinal movements and limb twitches. These behaviors, observed in a visually guided lineage far removed from vertebrates, challenge long-standing assumptions about the uniqueness of REM sleep. Building on these insights, we have begun systematically recording sleep behaviors across the spider tree of life. Our findings suggest that sleep is a universal feature in spiders, marked by distinct and robust behavioral signatures. This opens new avenues to explore the function and evolution of sleep—particularly REM sleep—outside the vertebrate lineage. I will present our latest results on spider sleep and outline key directions for future research, laying the foundation for an unmatched comparative framework in sleep research, with the potential to reshape our understanding of sleep across the animal kingdom.
Evolution of Social Wound Care Behaviours in Ants
Open wounds represent a significant risk of infection and mortality, driving diverse ant species to evolve sophisticated social wound care strategies. Megaponera analis employs therapeutic treatments on infected wounds with antimicrobial secretions from the metapleural gland, dramatically reducing mortality. Chemical analyses of these secretions identified numerous antimicrobial compounds and proteins. Conversely, Camponotus floridanus, lacking this gland, perform prophylactic limb amputations to halt infection spread. Dinoponera grandis conduct self-wound care using their front legs, while Eciton burchellii army ants exhibit “first aid” wound care behaviours near the raiding sites, followed by antimicrobial care inside the bivouac. These wound care behaviours highlight the evolutionary flexibility of cooperative behaviours under pathogenic pressures and the convergent emergence of functionally analogous solutions in response to a shared threat.
