In nature, survival and reproduction are the two of the most effective drivers that shape animal behavior. In evolutionary biology, the individual who makes a larger contribution to the gene pool of the next generation is said to be ‘fitter’ than other individuals. When reproduction plays such an important role in the life cycle of an animal, it is obvious that a lot of energy goes into attracting and securing mates. In many groups of animals like birds, anurans and orthopterans (a superfamily comprising of grasshoppers, locusts and crickets) intricate acoustic signals are performed by one gender to attract the other. Specifically for crickets it has been seen that the calling activity is a strong indicator of the male’s success. In a recent study researchers from the Indian Institute of Science, Bangalore have studied the all important calling behaviour in a wild population of field crickets, Plebeiogryllus guttiventris. They studied the variability in the call the males made on different nights and also the position from which these calls were made. Through the study they found that the calls of individual crickets varied on different nights and the males frequently changed the location from where they made the call. The change in location even though large was not seen to be directional. The study also shows that the male crickets often used energetically expensive features of calls like high intensity and high chirp rate. The study successfully shows that the two major factors influencing signaling behaviour, calling effort and calling intensity, are independent of each other. Thus gives us an interesting insight into the trade-off decisions made by crickets and furthering our understanding of these small critters.
Read time: 2 mins18 Aug 2017