Role of maternal odors on foraging behavior during postnatal development in a solitary subterranean rodent Ctenomys talarum

Abstract

We investigated the role of maternal odors emanating from excretory deposits and/or glandular secretions during the postnatal development of foraging and related behaviors in young Los Talas' tuco-tucos (Ctenomys talarum), a solitary rodent, under seminatural conditions. During cafeteria tests, we offered them two of the grasses most preferred by adults of this species (bromegrass, Bromus unioloides and panicgrass, Panicum racemosum). We scent marked one dietary option in a treatment group, and the other option in a second treatment group, keeping a third group with no odors as control. Pups did not show to prefer a special grass in particular, and maternal odors showed no effect on the behavioral variables evaluated in this study. When they reached their weaning age, they showed an ontogenetic change in food preferences, where they preferred bromegrass, and maternal odors influenced negatively on the consumption of panicgrass. During dispersal, preference for bromegrass was expressed independently of the presence of maternal odors. Overall, their effect was less pronounced than age's effect, and it was evident in only a subset of the conducted experiments. This study shows that the influence of maternal odors is not essential for the establishment of feeding or site preferences in this species in seminatural conditions, contrarily to what was observed in other studies performed with social mammal species (i.e., rats and rabbits). It is suggested that other factors (e.g., individual learning) might influence the observed preferences.

Diet selection and asocial learning: Natal habitat influence on lifelong foraging strategies in solitary large mammals

“…Animals need to adaptively rely on social and asocial learning based on a trade‐off between the cost of collecting information and its reliability (Kendal et al, 2005). Echeverría and Vassallo (2012) found that although diet selection during weaning might be influenced by the mother, maternal influence was not essential for diet selection during dispersal in solitary rodents ( Ctenomys talarum ). Additionally, Galef and Whiskin (2001) provided experimental evidence that socially enhanced food preferences weaken after animals have experienced alternative foods, especially high‐quality alternatives.…”

Functional morphology and identity of the thenar pad in the subterranean genus Ctenomys (Rodentia, Caviomorpha)

“…). In the case of Ctenomys , Echeverría & Vassallo () observed that, when foraging on the two preferred grasses, C . talarum (Los Talas’ tuco‐tuco) consumed both grasses through two different foraging techniques.…”

“…However, there are cases such as rats (Rattus) which show the ability to perform a more precise manipulation of the food, even with a single hand (see references in Whishaw et al 1998). In the case of Ctenomys, Echeverr ıa & Vassallo (2012) observed that, when foraging on the two preferred grasses, C. talarum (Los Talas' tucotuco) consumed both grasses through two different foraging techniques. When foraging on panicgrass (Panicum racemosum) individuals handled the culm using both hands at once and rotated it for peeling the cataphylls using their incisors.…”

Ontogenetic integration between force production and force reception: a case study inCtenomys(Rodentia: Caviomorpha)

“…Previous researches have shown that the digging behaviour in different species of the genus Ctenomys is already present shortly after birth (Echeverría ; Echeverría and Vassallo ). Yet, in those taxa, this particular conduct involves both force production and the corresponding force reception.…”