I used to hike a lot in the Santa Monicas. Prime rattler (& Poison Oak) territory.

As you know, there is some genetic variation in everything, and apparently also in rattle buzz volume. (Some go up to 11).

So in the park, the noisy rattlers are killed by the (stupid) hikers and the quiet ones go undisturbed.

Guess where this unnatural selection is taking us?

Verum audaces non gerunt indusia alba. - Ipsi dixit MCMLXXII