Discriminação de relativos em girinos canibais de Dendrobates auratus (Anura, Dendrobatidae)

Abstract

Kin discrimination in cannibalistic tadpoles of the Green Poison Frog,Dendrobates auratus (Anura, Dendrobatidae). Cannibalizing a related individual can reduce the inclusive fitness of the cannibal. Hence, mechanisms that allow a tadpole to recognize and modify its behavior toward kin may reduce the inclusive fitness costs of cannibalism. Alternatively, ecological factors may cause preferential treatment of kin to be too costly to be favored by selection. We tested these two predictions in the Green Poison Frog, Dendrobates auratus. The effect of kinship on larval cannibalism was examined through a series of kin-discrimination trials. The behavior of large tadpoles was observed when presented with two small, tethered tadpoles, one a clutchmate and one an unrelated tadpole. In these simultaneous presentation tests, tadpoles displayed a significant preference for attacking kin. In a series of timed trials, pairs of unequally sized tadpoles were placed together in containers. The majority (70%) of large tadpoles took less than 24 hr to consume the small tadpole. Kinship did not affect the survival time of the small tadpole. Our results are consistent with observations that D. auratus is an indiscriminate predator. As conspecifics may be serious competitors, their swift elimination would be an advantage, particularly in the small, nutrient-poor pools used by this species.

From habitat use to social behavior: natural history of a voiceless poison frog, Dendrobates tinctorius

“…2; Video S1; Rojas, 2014, 2015), where they remain unattended until metamorphosis, which occurs after approximately two months (B. Rojas, 2011, personal observation in the field). As in some other species of Dendrobates (Caldwell & de Araújo, 1998; Gray, Summers & Ibáñez, 2009; Summers, 1990; Summers & McKeon, 2004), larvae feed on detritus and on larvae of insects and frogs (Rojas, 2014), including conspecifics (Rojas, 2014, 2015; Video S1). In captivity, individuals take up to 18 months to reach maturity (Lötters et al, 2007), but their age at sexual maturity in the field is unknown to date.…”

Neural correlates of winning and losing fights in poison frog tadpoles

“…Prior to behavioral trials, we randomly sorted tadpoles into size-matched pairs, with all tadpoles used in this study approximately between Gosner stages 30 -34 (no substantial limb development). We did not exclude sibling pairs as poison frog tadpoles exhibit aggression and cannibalism indiscriminate of kinship [26,27,37]. We size-matched pairs because larger tadpoles are known to win aggressive encounters [26,27,37], and we were interested in neural correlates independent of this physical size advantage.…”

“…We did not exclude sibling pairs as poison frog tadpoles exhibit aggression and cannibalism indiscriminate of kinship [26,27,37]. We size-matched pairs because larger tadpoles are known to win aggressive encounters [26,27,37], and we were interested in neural correlates independent of this physical size advantage. To distinguish individuals during behavioral trials, we stained one randomly chosen tadpole from each pair using neutral red dye (Sigma-Aldrich, St. Louis, MO, USA) following previously established methods [38] and preliminary testing in our lab.…”

“…Species vary in their preferred pool size for tadpole deposition, where smaller pools tend to be predator-free but also nutrient poor, creating a trade-off between safety and nutrition [23]. Increased parental care in dendrobatid poison frogs is associated with resource limitation [23,24] and aggression in tadpoles [5,25,26].…”

Larval cannibalism in Phyllobates poison frogs

“…ephemeral pools) in which they develop (Polis and Myers 1985;Crump 1990Crump , 1992. Although tadpole cannibalism has been studied in a variety of contexts, such as kin recognition (Pfennig et al 1993;Pfennig 1997;Gray et al 2009), foraging behaviour (Caldwell and de Araujo 1998), phenotypic plasticity (Pfennig 1990(Pfennig , 1992, neuroethology (Fischer et al 2020), and parental care (Summers 1999;Downie et al 2001;Brown et al 2009;Rojas 2014), its prevalence across the amphibian phylogeny is not well known.…”