Unbalanced biparental care during colony foundation in two subterranean termites

Abstract

Parental care is a major component of reproduction in social organisms, particularly during the foundation steps. Because investment into parental care is often costly, each parent is predicted to maximize its fitness by providing less care than its partner. However, this sexual conflict is expected to be low in species with lifelong monogamy, because the fitness of each parent is typically tied to the other's input. Somewhat surprisingly, the outcomes of this tug‐of‐war between maternal and paternal investments have received important attention in vertebrate species, but remain less known in invertebrates. In this study, we investigated how queens and kings share their investment into parental care and other social interactions during colony foundation in two termites with lifelong monogamy: the invasive species Reticulitermes flavipes and the native species R. grassei. Behaviors of royal pairs were recorded during six months using a non‐invasive approach. Our results showed that queens and kings exhibit unbalanced investment in terms of grooming, antennation, trophallaxis, and vibration behavior. Moreover, both parents show behavioral differences toward their partner or their descendants. Our results also revealed differences among species, with R. flavipes exhibiting shorter periods of grooming and antennation toward eggs or partners. They also did more stomodeal trophallaxis and less vibration behavior. Overall, this study emphasizes that despite lifelong monogamy, the two parents are not equally involved in the measured forms of parental care and suggests that kings might be specialized in other tasks. It also indicates that males could play a central, yet poorly studied role in the evolution and maintenance of the eusocial organization.

Efficient but occasionally imperfect vertical transmission of gut mutualistic protists in a wood‐feeding termite

“…The efficiency of this second step of protist transmission, which was previously referred as the β component of transmission (i.e., the probability β ), was not studied and currently remains unknown. However, several recent studies conducted on R. grassei and other Reticulitermes species suggest that the probability β could be very high and even close to 1 (Brossette, Meunier, Dupont, Bagnères, & Lucas,; Shimada et al, ). These studies showed that the two primary reproductives founding an incipient colony have numerous opportunities to transfer their gut symbionts to the first larvae produced in the young colony.…”

“…These studies showed that the two primary reproductives founding an incipient colony have numerous opportunities to transfer their gut symbionts to the first larvae produced in the young colony. Queens and kings keep their gut protists for quite a long period (Shimada et al, ) and regularly exhibit proctodaeal trophallaxis with their larvae (Brossette et al, ). This behaviour probably allows the transfer of most gut protists to the first cohort of workers, which in turn will propagate them by proctodaeal trophallaxis to all members of the colonies and thereby ensure the perpetuation of protists within the colony .…”

High Exploration Behavior of Termite Propagules Can Enhance Invasiveness

“…Indeed, R. flavipes and R. grassei are sympatric in the sampling area of the current study (Oléron) where they display differences in their life history traits. Both species exhibit extended families (i.e., the presence of multiple neotenic reproductives), but they differ in traits like parental care (Brossette et al, 2019), colony foundation (Brossette et al, 2017) and aggressiveness (Perdereau et al, 2011;Duarte et al, 2018). Feeding at multiple sites is a common trait for R. flavipes, while less than half of the colonies of R. grassei exhibit this trait in the studied population (Deheer et al, 2005).…”

“…Overall, our study highlights the greater short-term exploration capacity of the invasive species, R. flavipes, compared to the two other Reticulitermes species studied. Together with its capacity for developing numerous reproductives, reduced intraspecific aggression, rapid colony foundation, and elevated interspecific competitive ability (Perdereau et al, 2011;Brossette et al, 2017Brossette et al, , 2019, this enhanced exploration activity may promote its invasiveness. Greater exploration activity not only increases species dominance and facilitates the monopolization of resources, but also increases propagule pressure, which is an essential component of dispersal.…”

Biogeography and Independent Diversification in the Protist Symbiont Community of Heterotermes tenuis

“…Such losses are more common for some host species than others, and for some protist species than others (Kitade and Matsumoto, 1993;Kitade et al, 2013;Michaud et al, 2020). Protists are inherited biparentally: both king and queen contribute their symbionts to the nascent colony's microbial community (Shimada et al, 2013;Brossette et al, 2019). Host outcrossing can therefore allow complementation of these deficient communities, helping to maintain a consistent protist community across the host species' range (Michaud et al, 2020).…”