Orangutan kisses point to dawn of spoken language

New research may help to unlock the mystery of why and how our evolutionary ancestors first combined a consonant with a vowel to make the first word. Kiss squeaks The research, led by Dr Adriano Lameira of the Department of Anthropology , is published Human Behaviour. The study has analysed over 4,400 individual recordings of voiceless consonant-like calls, or 'kiss squeaks', from 48 orangutans in four different populations. Orangutans are unique among non-human primates as their predominant call type, the 'kiss squeak', is voiceless. The aim of the research was to understand whether these voiceless calls, which can also include lip-smacks, clicks and raspberries, could transmit similar information to voiced calls, which more closely resemble vowel-like sounds. The team believes that understanding what information these consonant-like 'kiss squeaks' contain would help to piece together how and why the earliest combinations of vowel-like and consonant-like sounds may have occurred. Non-vocal information Researchers already know that population membership, body size, individual identity and situational circumstances can be conveyed in the sound frequency and duration of voiced, vowel-like calls in other primates.