The faint whistling of birdsong awoke Marcs as it crept into his cell.
So birdsong is a mixture of pre-programmed knowledge of their species song and learning from older singing males.
The usual explanation for birdsong is that the birds are singing to attract mates or to announce the limits of their territory.
Many studies have been done exploring the degree to which birdsong is innate or learned behavior.
Plus why oh why did they introduce unnecessary twittering birdsong on one track?
Initially he proposed to explain birdsong as a display, enabling a discerning female to select a mate from among a number of males.
In a second, the air filled with birdsong , the number of birds doubling and redoubling, blocking out the sun.
No more beautiful birdsong , no more beautiful birds flying beautifully in the sky.
Already the air was warm, underscored by a chatter of birdsong and the muted clop-clop from their horse's hooves.
Ornithologists also know something about how birdsong is produced.