Orangutan 'Rocky' Copies Human Sounds, Opens New Link Between Ape-Man Lineages?

An orangutan has demonstrated the ability to copy human sounds. A feat that offers new clues to human development, it now opens new doors towards understanding how human speech evolved from the communications of the great apes.

University of Durham study led by Dr. Adriano Lameira from the UK confirmed that the great apes were able to produce human sounds and that human speech has originated from them.

Rocky, the orangutan, mimicked more than 500 vowel-like noises similar to words in a conversational context. It suggested that animals of the species have an ability to control his voice and make new sounds, New Scientist reported.

Dr. Lameria proposes that this may be a potential for them to discover more about the vocal capacities of early hominids that lived before the split between the orangutan and human lineages. This may also lead them to learn how the vocal system evolved towards full blown speech in humans.

During the study, the scientists engaged Rocky in a few rounds of do-as-I-do in his home, the Indianapolis Zoo. The drill required him to copy the person's sounds before he could get his snack, Popular Science reported.

In the imitation game, Rocky demonstrated the ability to control his vocalizations up and down in pitch and in tone to match the experimenter. The orangutan also showed the ability to make calls that resembled both consonant and vowel sounds.

The scientists examined Rocky's exclamations against a database of more than 12,000 hours of wild and captive orangutan calls and discovered that his sounds fell outside the repertoire of normal orangutan vocalizations. The scientists then concluded that the orangutan can achieve levels of volitional voice control in ways crucial for conversation that is qualitatively comparable to those manifested in humans.

The orangutan's ability to exhibit vocal skills, however, does not show that Rocky is a bizarre or an abnormal species. In a previous study, Dr. Lameira discovered a female orangutan named Tilda at Cologne Zoo in Germany that was able to produce sounds with a similar pace and rhythm to human speech. The researchers were also astounded by the female orangutan's vocal skills but could not prove they had been learned.