The Littlest Birds Sing the Prettiest Songs — or do they?

According to this video testimony from musical performers The Be Good Tanyas, ‘the littlest birds sing the prettiest songs’. If we take their claim at face value, one might presuppose that ‘size of bird’ and ‘prettiness of song’ might be connected in some form of linear relationship where smaller birds sing prettier songs:

However, as they fail to clarify the nature of the relationship between ‘size of bird’ and ‘prettiness of song’ one could postulate that the following examples also satisfy their description:

Thus we feel that — in the absence of supporting data — their observation that smaller sized avians produce more pleasing vocalizations, should not be regarded as a relationship which necessarily suggests that larger-sized birds sing notably less pretty songs.

Regardless of whether there is a relationship between these two metrics, we might still expect to find supporting evidence for the notion that diminutive avians produce trillings, warblings, and other chirruping-like sounds that are of a fetching nature.

One might therefore assume that the songs of Hummingbirds should be among the prettiest of all bird songs. However, according to the Hummingbird-themed site World of Hummingbirds:

“the sounds of hummingbirds are not exactly considered music…it would be more appropriate to call them chirps then it would be to call it music.”

This testimony, along with the audio evidence provided on their site, suggests that the claims of The Be Good Tanyas should not be taken at face value. Further undermining their claims is this list of the top ten song birds from ‘Bird On! News’. While some of the entries on this list also feature in whatbird.com’s list of small-sized birds (those birds 5–9 inches in length), the top 10 list also includes the mute swan which can grow up to 1.5 meters in length, a size described by Wikipedia as ‘impressive’.

Without published data in a peer-reviewed journal we find the evidence to support any claim that ‘the littlest birds sing the prettiest songs’ to be lacking and we humbly request that The Be Good Tanyas ‘show us the data’.