Death-feigning behavior in Microhyla berdmorei, M. butleri, and M. heymonsi (Anura: Microhylidae) from Peninsular Malaysia

Phyllomedusa 19(1), June 2020 Anurans live in various types of environments and are exposed to different predators, such as snakes, fishes, birds, small mammals, and larger invertebrates such as spiders (Duellman and Trueb 1986, Wells 2007). Anurans have evolved a wide array of defensive mechanisms to survive; these include immobility, escape, death feigning (thanatosis), leg stiffening, legs interweaving, skin secretions, body contraction, and the unken reflex (Duellman and Trueb 1986, Toledo et al. 2011). Death feigning—a state of immobility that many species of anurans employ in response to external stimuli—has been considered to be a defensive mechanism (Miyatake et al. 2004). In death feigning, the animal “pretends” to be dead when it is threatened or attacked by a potential predator (McFarland 1982, Toledo et al. 2010). According to Humphreys and Ruxton (2018), death feigning or tonic immobility (TI) is the innate adoption of a motionless posture by a