External gills usually contains muscle tissue, and may be moved by the animal as a free appendage, in order to stir up stagnant water. The stalk is lined by many thinly walled filaments (fimbriae), containing the majority of blood vessels used in gas exchange. Animals usually have one external gill originating on each gill arch (except the hyoid), which leads to there being three pairs of external gills in salamanders, and four in the gilled larvae of lungfish. External gills External gills are the gills of an animal, most typically an amphibian, that are exposed to the environment, rather than set inside
How Many Birds How Many Birds "How Many Birds" is a song written by Barry Gibb, recorded by the Bee Gees in 1966 for the "Spicks and Specks" album. Recording took place at St. Clair Studios, Hurstville outside Sydney. The song was recorded on one-track tape machines and required the use of sound-on-sound for all overdubs. "How Many Birds" was recorded around April and May 1966 as part of the sessions for what became the Spicks and Specks album. The song starts with a guitar riff and the chord became E as Barry sings the introduction. After Barry sings the lines, the song