The evolution of self-medication behaviour in mammals

Abstract

Self-medication behaviour is the use of natural materials or chemical substances to manipulate behaviour or alter the body’s response to parasites or pathogens. Self-medication can be preventive, performed before an individual becomes infected or diseased, and/or therapeutic, performed after an individual becomes infected or diseased. We summarized all available reports of self-medication in mammals and reconstructed its evolution. We found that reports of self-medication were restricted to eutherian mammals and evolved at least four times independently. Self-medication was most commonly reported in primates. Detailed analyses of primates suggest that self-medication is a life-history trait associated with body size, absolute brain size and longevity, but we found no support for the hypothesis that self-medication evolved to reduce the costs of social living. Large, longer-lived species might thus benefit uniquely from self-medication.

Host Cognition and Parasitism in Birds: A Review of the Main Mechanisms

“…Gibbons in Thailand are also thought to use Gironniera nervosa leaves for similar purposes (Barelli and Huffman, 2017). A recent comparative analysis found that primate species with a larger absolute brain are more likely to self-medicate, suggesting that self-medication is, to some degree, cognitively demanding (Neco et al, 2019).…”

Phenomenology Applied to Animal Health and Suffering

“…As the large literature on self-medication behaviour in animals (see Neco et al 2019) suggests, animals may be acutely aware that something has 'gone wrong' with their bodies. For example, rodents in pain will voluntarily self-administer analgesic medications when given the opportunity (Martin and Ewan 2008).…”

“…For example, rodents in pain will voluntarily self-administer analgesic medications when given the opportunity (Martin and Ewan 2008). As another example, wild primates will treat internal parasites by eating whole leaves and external parasites by rubbing their skin with acidic plant parts, and even in some cases with millipedes (Neco et al 2019). The phenomenological experiences of animals, the positive and negative experiences that constitute welfare, do not just impact the body, but also the workings of the mind itself, in ways the animals respond to.…”

Homo medicus: The transition to meat eating, increased pathogen pressure, and the constitutive and inducible use of pharmacological plants in Homo

“…Positive Negative evolved to co-opt plant and fungal toxins to prevent or treat their own infections, a phenomenon termed self-medication or zoopharmacognosy (de Roode et al, 2013;Huffman, 1997Huffman, , 2017Neco et al, 2019;Rodríguez & Wrangham, 1993;Villalba & Provenza, 2007;Wrangham & Nishida, 1983). A systematic review of self-medication in mammals and its relationship to life history traits found reports of self-medication in 71 species from 7 mammalian orders, with the most reports in Primates (46 species), Carnivores (10 species), and Rodents (5 species) (Neco et al, 2019).…”

“…Positive Negative evolved to co-opt plant and fungal toxins to prevent or treat their own infections, a phenomenon termed self-medication or zoopharmacognosy (de Roode et al, 2013;Huffman, 1997Huffman, , 2017Neco et al, 2019;Rodríguez & Wrangham, 1993;Villalba & Provenza, 2007;Wrangham & Nishida, 1983). A systematic review of self-medication in mammals and its relationship to life history traits found reports of self-medication in 71 species from 7 mammalian orders, with the most reports in Primates (46 species), Carnivores (10 species), and Rodents (5 species) (Neco et al, 2019). Types of self-medication included ingestion of whole leaves to expel parasites from the digestive system (mostly apes and elephants), rubbing fur with toxic plants (non-human primates), placement of bay foliage around the nest to reduce ectoparasites (rodents), and use of specific plants to attenuate negative effects of food ingestion (artiodactyls).…”