Figure 1
From: Universal principles underlying segmental structures in parrot song and human speech
Complex vocalizations of the human and the budgerigar. In human language, silence is not a reliable cue for word, syllable, or segment boundaries. For instance, the complex and novel phrase “the zealous sailors sail all seven seas and all four oceans” can be spoken without any intervening silence, as shown in the spectrogram (A). Budgerigar song seems to share this property. Budgerigar song is comprised of complex (B: syllables 3 and 5) and simple (B: syllables 1, 2, 4, 6, 7) syllable types. The complex syllables (C), however, seem to be composed of segments which are similar to the simple syllables. We created the image using R and the packages cowplot, ggplot2, ggpubr, seewave, and viridis19,20,21,22,23.
