Termites like it hot and humid: the ability of arboreal tropical termites to mediate their nest environment against ambient conditions

Abstract

Tropical termites are physiologically adapted to a narrow range of climatic conditions, and as a result may be particularly impacted by global climate change. Because of their key roles as decomposers and ecosystem engineers, any climatic impact on termites could have serious ramifications for tropical ecosystems. The ability of termites to mediate their nest environment could allow them to cope with these changes. The temperature and RH in nests of the tropical termite Nasutitermes acajutlae were compared with ambient conditions on the island of St John, U.S. Virgin Islands, over a 5‐year period using data loggers inserted into nest cartons. Nest conditions were found to be significantly warmer, more humid, and less variable than ambient conditions with respect to both temperature and RH. A comparison of dead nests, live non‐reproductive nests, and live reproductive nests revealed that temperature mediation appears to be primarily the result of the presence of termites, with reproductive nests producing the highest temperatures, while high RH is maintained by the insulating effects of the nest material. Environmental variability across the years of this study had a significant influence on nest temperature and RH, suggesting that if tropical conditions become warmer and drier as predicted, N. acajutlae may have difficulty adapting over the long term.

Desiccation tolerance of Termitidae termites in relation to their nest type

“…Termites in family Termitidae are renowned for their capacity to epigeal and arboreal nests, which are well known for their capacity to regulate and maintain a high level humidity within nest (Korb and Linsenmair 1999, Korb 2003, Fuller and Postava-Davignon 2014, King et al 2015, Katariya et al 2018). The regulation of environmental humidity is believed to benefit and optimize the reproduction and survival of termites (Steward 1983, Noirot and Darlington 2000).…”

“…The evolution and function of epigeal and arboreal nests have been postulated to be associated with predator defense and microclimate regulation (Noirot and Darlington 2000), such as ventilation, temperature, and humidity control in mounds of Macrotermes and Odontotermes (Korb and Linsenmair 1999, Korb 2003, King et al 2015, Katariya et al 2018). In addition, temperature and humidity control were also observed in arboreal nest constructed by Nasutitermes (Fuller and Postava-Davignon 2014).…”

Atrazine Exposure Influences Immunity in the Blue Dasher Dragonfly, Pachydiplax longipennis (Odonata: Libellulidae)

“…For example, increased energy channeled to immunity could result in decreased energy available for reproduction. Insect investment in immunity can change in response to a number of environmental factors such as temperature ( Fedorka et al 2013a , Fuller and Postava-Davignon 2014 , Kutch et al 2014 ), season ( Fedorka et al 2013b ), and previous exposure to pathogens ( Mikonranta et al 2014 ). Individuals with increased investment in immunity may have less energy to devote to reproduction ( Schwenke et al 2016 ) or behaviors such as dispersal ( Suhonen et al 2010 ), predator avoidance ( Rantala et al 2010 ), or predation ( St. Clair and Fuller 2014 ).…”

An adapted typology of tree-related microhabitats including tropical forests

“…However, extending the TreM types invertebrate nests and carton nests in size and form might be required in the future to capture the larger variety presented in the tropics. The microclimate in carton nests is warmer, more humid and less variable than ambient conditions (Dechmann et al, 2004; Fuller and Postava-Davignon, 2014). Moreover, this microhabitat is used by a variety of organisms, including some vertebrates.…”