This article suggests that pregnant rattlesnakes might give their offspring a better chance of survival if they congregated for birth. If that were true, one might expect that there would also be a convergence of birth times. While doing research over 25 years ago, we had five of six pregnant rattlesnakes caged together all give birth the same evening. Coincidence? Pheromones? Common environmental trigger? I agree that the efforts of these mothers, which even forgo eating, are “heroic.”

John Galligan
Pottstown, Pa.