Shorebird chicks hatch into a dangerous world, so they need to be vigilant from the start. Researchers in Australia noticed that some shorebird chicks began chirping in their final days in the egg. The chirps fell silent when the researchers played recordings of a Little Raven, which hunts for young birds. The finding suggests the chicks are listening carefully and may be able to tell threatening sounds from non-threatening ones. Learn more at BirdNote.org.