This instability either causes or signals an aneurysm. “Fluttering is a mechanical signature of future growth,” Patankar said. Capturing the underlying physics To quantify the transition from ...

Fluttering Feathers Could Spawn New Species Fork-tailed flycatchers make a fluttering sound with their wings—but separate subspecies have different “dialects” of fluttering.

Birds tweet, squawk, chirp, hoot, cluck, and screech to communicate with each other. Some birds have found another way to talk, though: they make sounds by fluttering their feathers or smacking ...