A Test of Local Enhancement in Amphibians

Abstract

Local enhancement is an underexplored social learning mechanism that is often observed in organisms that live in groups. This mechanism occurs when individuals are attracted to areas where conspecifics have previously been, but which are not present when the animal actually moves into the area. We tested for local enhancement in wood frog tadpoles (Lithobates sylvatica) and spotted salamander larvae (Ambystoma maculatum) in three experiments that exposed individuals to one side of a test chamber which was empty and another that contained a group of three conspecifics. Side preference of the focal individual was recorded once the conspecifics were removed. Tadpoles showed a clear preference for moving to areas where a group of tadpoles had previously been located. Conversely, this preference was not observed in salamander larvae. In addition, salamander larvae took significantly more time to initially choose a side. These results indicate that tadpoles exhibit local enhancement, whereas aquatic salamander larvae do not. This difference in social learning could be largely due to differences in aquatic ecology between tadpoles and salamander larvae.

Tadpole plasticity shapes the potential benefits of egg feeding to poison frog parents

“…In a similar vein, although larval cannibalism is widespread in amphibians including poison frogs (Brown, Morales, & Summers, 2008b; Crump, 1983; Elgar & Crespi, 1992), tadpoles of the obligate egg‐feeder O. pumilio kill, but do not eat, conspecifics (Dugas, Wamelink, et al, 2016). Observations of and interactions with conspecifics can increase the probability that foragers consume novel food items (Chapman et al, 2015; Crane et al, 2018), and the notable absence of conspecifics in single‐occupancy nurseries may be a cost of this derived reproductive strategy (Lehtinen, 2004). Broadly, testing for the predicted indirect fitness benefits of parent‐facilitated consumption of eggs, fertilized or not, is critical to understanding the evolution of trophic egg feeding (Perry & Roitberg, 2006), and critical any time indirect fitness is invoked as an ultimate explanation for a proximate phenomenon (Mock & Parker, 1997).…”

Observational spatial memory in wolves and dogs

“…Social learning, i.e. learning influenced by observation of or via interaction with another individual or its product [1], is highly adaptive and has been shown to play an important role in many species including birds, fishes, mammals, and marsupials with regard to food acquisition, predator recognition and avoidance, mate choice and intraspecific communication [2][3][4][5]. Several mechanisms of social learning have been observed across animal species [6,7], however, the most common one might be stimulus enhancement (drawing attention to an object) and local enhancement (drawing attention to a location) [3,6,8].…”

Attraction to conspecifcs in Rhinella icterica and R. ornata tadpoles (Anura: Bufonidae)

“…Recognition mechanisms (of relatives, conspecifics, mates, neighbours, rivals, prey or predators) are essential for survival, reproduction and social interactions between organisms (Sherman et al 1997). Among anuran larvae, chemical communication plays a key role in several behaviors, such as communication between a female and its offspring (Kam & Yang 2002;Stynoski & Noble 2012), detection of alarm cues in prey-predator contexts (Hews 1988;Hokit & Blaustein 1995;Summey & Mathis 1998;Kiesecker et al 1996Kiesecker et al , 1999, intraspecific competition (Glennemeier & Denver 2002), microhabitat and food discrimination (Pfening 1990;Gamboa et al 1991;Hall et al1995;Sontag et al 2006), and recognition of predators (Petranka et al 1987;Lawler 1989;Kiesecker et al 1996), conspecifics (Leu et al 2013;Chapman et al 2015;Raven et al 2017), and kin (Blaustein & O'Hara, 1982;Waldman 1986;Rajput et al 2014;Pizzatto et al 2016;Raven et al 2017).…”