> I don't see how even an entire chicken is going to meaningfully respond to a wavelength of almost 50 meters.

Without disputing the conclusion, is the wavelength the right measurement, or should that be half the wavelength?

That's a more natural way to consider the resonance, certainly. What I was getting at is that if we were using a 7hz tone to explore a big room, we couldn't tell if there was a chicken in there or not. We'd have a hard time sensing an elephant. Let alone exert enough of a force to harm. Because the wave is so much larger that they barely interact.