Researchers from Osaka University and University of Tsukuba have used empirical data on male Japanese tree frogs to demonstrate that (1) neighbouring male frogs avoid call overlaps with each other over a short time scale and (2) they collectively switch between the calling state and the silent state over a long time scale. The authors proposed a mathematical model that separates dynamical models spontaneously switched due to a stochastic process depending on the internal dynamics of respective frogs and also the interactions among the frog.
Their goal is to find a way in designing more effective wireless sensor networks. First, they recorded the vocal interplay of neighboring tree frog calls, which they found allowed trade-off time for individual communication, though this is interspersed with more random collective silence and choruses. Then, they mathematically modeled these patterns and effectively applied their model toward the control of a wireless sensor network.
“The team looked at the calling patterns of male Japanese tree frogs over different time intervals. To do so, they placed three frogs in individual inside cages and recorded their vocal interplay. They found the frogs both avoided overlapping croaks and collectively switched between calling and silence. The researchers then created a mathematical model to adapt the frogs’ acoustic teachings for technological benefit, as such patterns are similar to those valued in networks. The findings are reported in the journal Royal Society Open Science”
“We found neighboring frogs avoided temporal overlap, which allows a clear path for individual voices to be heard,” study co-author Daichi Kominami explains. “In this same way, neighboring nodes in a sensor network need to alternate the timings of data transmission so the data packets don’t collide.”
“We modeled the calling and silent states in a deterministic way,” according to lead author Ikkyu Aihara, “while modeled the transitions to and from them in a stochastic way. Those models qualitatively reproduced the calling pattern of actual frogs and were then helpful in designing autonomous distributed communication systems.”
Such systems must cleverly regulate give and take, activity and rest. Therefore, as the third part of the study, the researchers leveraged the model for data traffic management in a wireless sensor network. These networks are a key component in the Internet of things, as their dispersed sensor nodes measure and communicate different environmental characteristics. Then, through complex coordination, collected data are fed to a central system.
They found the short-time-scale alternation was especially effective at averting data packet collisions. Meanwhile, the cyclic and collective transitions in the long time scale offered promise for regulating energy consumption.
“There is a dual benefit to this study,” co-author Masayuki Murata says. “It will lead both to greater biological knowledge in understanding frog choruses, and to greater technological efficiency in wireless sensor networks.”
Journal Reference Source:
- Ikkyu Aihara , Daichi Kominami , Yasuharu Hirano and Masayuki Murata. Mathematical modelling and application of frog choruses as an autonomous distributed communication system. Royal Society Open Science, 2019 DOI: 10.1098/rsos.181117