Just to let you know how far scientists will go to learn about nature, you can read about the cat telephone. In 1929 two Princeton researchers, Ernest Glen Wever and Charles W. Bray, removed part of a cat’s skull and most of its brain to attach one electrode to the animal’s right auditory nerve and a second electrode to another area on the cat’s body. Those electrodes were then hooked up to a vacuum tube amplifier. After amplification, the signals were sent to a telephone receiver.

The researchers noted that, “Speech was transmitted with great fidelity. Simple commands, counting and the like were easily received. Indeed, under good condition the system was employed as a means of communication between operating and sound-proof rooms.”

To read more about the cat telephone, click here.