black-capped squirrel monkey, and Peruvian spider monkey. Monkeys, scientists found, had a secret yodelling weapon; the primates possess special anatomical structures in their throats called vocal ...

The monkeys' "ultra-yodels" had frequency leaps that were five times larger than human frequency changes, often exceeding ...

By-Stephane-Thomas.jpeg) A mother Peruvian spider monkey and her baby in the Amazon ... I felt a lump in my throat. I stroked her black fur. That night, she wouldn’t let go.

These included the black and gold howler monkey, black-capped squirrel monkey and Peruvian spider monkey. A Peruvian spider monkey. (Dr Jacob Dunn/ Anglia Ruskin University/ PA) New World monkeys ...