Chimpanzees, It Turns Out, Have Accents

Chimpanzees, it now appears, have regional accents. Scientists have reported that young chimpanzees living in different corners of Africa do not sound alike, and that the gap between them widens as the animals grow older.

Simpanse, ternyata, punya logat daerah masing-masing. Para ilmuwan melaporkan bahwa simpanse muda yang tinggal di berbagai penjuru Afrika tidak bersuara sama, dan bahwa perbedaan di antara mereka semakin melebar seiring bertambahnya usia hewan-hewan itu.

The research team worked through more than eleven thousand recorded calls from infants and juveniles at two sites, a rescue centre in Zambia and a national park in Tanzania. They sorted the recordings into grunts, whimpers and laughter, then measured them. The youngest animals sounded broadly alike regardless of location. The older ones did not: each group had drifted toward its own particular manner of grunting.

Tim peneliti menelaah lebih dari sebelas ribu rekaman suara dari bayi dan simpanse remaja di dua lokasi, sebuah pusat penyelamatan di Zambia dan sebuah taman nasional di Tanzania. Mereka menyortir rekaman itu menjadi dengusan, rengekan, dan tawa, lalu mengukurnya. Hewan-hewan termuda bersuara kurang lebih sama tanpa memandang lokasi. Yang lebih tua tidak: setiap kelompok telah bergeser menuju cara mendengus khasnya sendiri.

That drift is the arresting part, since chimpanzee calls were long presumed fixed at birth, encoded in the animal rather than absorbed from its neighbours. If a young chimpanzee is instead soaking up the sound of the group around it, much as a child absorbs the vowels of a particular street without being taught them, then accent may be an older habit than anyone had been prepared to admit.

Pergeseran itulah bagian yang mencolok, karena suara simpanse sudah lama dianggap tetap sejak lahir, tertanam dalam hewan itu sendiri, bukan diserap dari tetangganya. Jika simpanse muda ternyata justru menyerap suara kelompok di sekelilingnya, mirip seperti seorang anak menyerap vokal khas suatu daerah tanpa pernah diajari, maka logat mungkin adalah kebiasaan yang jauh lebih tua dari yang pernah dibayangkan siapa pun.