38. Songs of ruby-crowned kinglets.
6. Song Learning Often Creates Complex Songs and Large Repertoires
Small to large repertoires
From page 86 in the book.
Songs of ruby-crowned kinglets. Under what conditions do these kinglets sing complete songs? When do they stop with incomplete songs, and when do they add calls to their performance? Compare all this variety to the seemingly invariant song of the savannah sparrow, for example—see below. I'm also curious about those two-syllable and three-syllable endings, which are readily distinguished by ear. How are they distributed geographically? Are there small dialects of the two forms distributed throughout the range? I have read that western birds tend to have the two-syllable tee-LETT endings, eastern birds the three-syllable tee-da-LETT. Is this true? Someone needs to plot these two song forms on a map so that we have some clear answers.