Anna’s hummingbird
Chapter 5: More about Song Learning
Subchapter: Song (and call) dialects
From page 69 in the book.
Photo by John Van de Graaff
♫315. Dialect 1, male 1. Listen to a number of his songs excerpted from several hours of recording, but realize that your ears can't begin to hear the details. Those details emerge only when songs are slowed down. (3:14)
In ♫316, listen to one of those songs at normal speed, then to that same song slowed to half, quarter, and one-eighth speed. There's more! He clearly uses two voice boxes to produce those songs. Spanning the first two notes in that dainty 16-note series of tiny, pure tones is a higher note, sung simultaneously, revealing the voice of the second syrinx. (0:52)
In ♫317, with the single high note isolated on the left track, the series of lower notes on the right track, listen for the two voices in the first split-second of these recordings slowed to 1/8, 1/16, and 1/32 speed (see book text for more details). March 19, 2017. Montaña de Oro State Park, Los Osos, California. (0:21).
♫318. Dialect 2, male 2. March 23, 2017. Anza-Borrego Desert State Park, Borrego Springs, California. (2:04)
♫319. Dialect 3, male 3. March 12, 2017. Morro Bay State Park, Morro Bay, California. (1:18)
♫320. Dialect 3, male 4, a neighbor of Male 3. March 12, 2017. Morro Bay State Park, Morro Bay, California. (0:45) Recorded by Janet Grenzke.
Exploring the differences in dialects: One song from each of the above four males at normal speed (♫321), half speed (♫322), and quarter speed (♫323). For the finale, just listen to the scrapes from each male at quarter speed (♫324). Do you hear three dialects? It's a challenge, but in the scrapes I hear how the first three are strikingly different from each other, representing three different dialects, and how the last two are similar, representing two individuals from the same dialect. (0:41, 1:07, 2:06, 0:53)
♫321—one song from each of four males.
♫322—those four songs at half speed.
♫323—those four songs at quarter speed.
♫324—the four scrapes at quarter speed.