Evolution of communication signals and information during species radiation

Abstract

Communicating species identity is a key component of many animal signals. However, whether selection for species recognition systematically increases signal diversity during clade radiation remains debated. Here we show that in woodpecker drumming, a rhythmic signal used during mating and territorial defense, the amount of species identity information encoded remained stable during woodpeckers’ radiation. Acoustic analyses and evolutionary reconstructions show interchange among six main drumming types despite strong phylogenetic contingencies, suggesting evolutionary tinkering of drumming structure within a constrained acoustic space. Playback experiments and quantification of species discriminability demonstrate sufficient signal differentiation to support species recognition in local communities. Finally, we only find character displacement in the rare cases where sympatric species are also closely related. Overall, our results illustrate how historical contingencies and ecological interactions can promote conservatism in signals during a clade radiation without impairing the effectiveness of information transfer relevant to inter-specific discrimination.

Testosterone amplifies the negative valence of an agonistic gestural display by exploiting receiver perceptual bias

“…Finally, to assess the functional relevance of our findings, we tested whether T's impact on foot-flag geometry and speed profile provides receivers with enough information to discriminate among high and low T males. We approached this issue computationally, using linear discriminant analyses (LDA) to model feature-related algorithms that help receivers detect and classify visual stimuli, mirroring other animal communication studies [32,33]. Such algorithms are especially enlightening to studies like ours because they model object discrimination in a way that is very similar to that of the anuran feature analysers [24].…”

Sister species diverge in modality‐specific courtship signal form and function

“…Understanding the origin and maintenance of such signal diversity remains at the heart of many evolutionary studies. Research testing the relative roles and importance of different drivers of signal divergence—for example, ecological, genetic, and social/sexual selection—remains an active and stimulating field of study (Bailey et al., 2019; Derryberry et al., 2018; Garcia et al., 2020; Hebets et al., 2013; Wilkins et al., 2018).…”

Tree Removal Changed The Drumming Behaviour of A Japanese Pygmy Woodpecker

“…In the present study, the author studied the drumming activities of Japanese pygmy woodpecker (Dendrocopos kizuki) in the Satoyama landscape of Japan. The Japanese pygmy woodpecker is endemic to Japan but only few studies have reported the biology and behaviour [1][2][3][4][5][6] of the species. To illustrate how acoustic patterns can re ect individual characteristics, author adopted dawn recordings of an individual Japanese pygmy woodpecker over an observation period of ve years.…”

“…Moreover, research on woodpecker communities showed that as long as drums are acoustically as different as those detected in the entire clade, species within a community do not need drums which sound as different as possible 1 . However, the bird observed in this study did not drum on trees, but always drummed the metal plate of a phone pole.…”

“…Simulations of virtual woodpecker communities with species having similar, different, or random drumming types, revealed that communities with distinct drumming types have an advantage compared to communities with similar types 1,7,8 . Simulations also showed that the actual communities had performances with wide ranges from longer drumming to shorter drumming in behavioural similar response when compared to communities with randomly sampled species 9 .…”