You'll probably encounter more howler monkeys than tourists amid the intricately carved stelae and temples where the " Jaguar" clan thrived from 500 to 700 A.D.
To study the animals' roars, the team measured the volume of a howler bone in their throats which act like a resonator, the larger that bone, the deeper that voice.
The " babies are very delicate, they can't be in a house where there are dogs or cats" because they have diseases that can be deadly for howler monkeys, he said.
" Why are they all sending Howlers? " asked Ginny, who was mending her copy of One Thousand Magical Herbs and Fungi with Spellotape on the rug in front of the living room fire.