Reposted by Jonathan Drury
I absolutely love this paper -- Menezes & Podos in Evolution demonstrate that loudness is linked to body size and gap width, but apparently not to habitat or mating system, across 123 Brazilian & US species.
academic.oup.com/evolut/advan...
academic.oup.com
Evolutionary drivers of vocal amplitude in birds
Birds can surpass all other terrestrial vertebrates in vocal amplitude, yet why some birds sing louder than others remains unclear. Using calibrated field