The "best possible approximation" of Ötzi the Iceman's voice has been reconstructed by scientists who aimed to discover the timbre and color of his Stone Age vowels.

Ötzi broke his silence with a deep male voice after 5,300 years at the EURAC Institute for Mummies and the Iceman in Bolzano.

He spoke Italian -- but just vowels, as you can hear below.

The experiment was presented on Wednesday morning during a major congress to celebrate the 25th anniversary of the mummy's discovery in the Ötztal Alps in South Tyrol.

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"We can't say we have reconstructed Ötzi's original voice because we miss some crucial information from the mummy," Rolando Füstös, chief of the ENT department at Bolzano's General Hospital, told Discovery News.

"But with two measurements, the length of both the vocal tract and the vocal cords, we have been able to recreate a fairly reliable approximation of the mummy's voice. This is a starting point for further research," he added.

Füstös and colleagues Francesco Avanzini, ENT specialist and phoniatrician at the city's General Hospital, Piero Cosi, at the Institute of Cognitive Sciences e Technology, National Research Council in Padova, Andrea Sandi, at SINTAC Biomedical Engineering in Padova,and others based their research on the CT scans of the mummy to create a model of his vocal tract.

"The vocal chords are the source of the vocal sound, but the main contribution to it is given by the selective filtering accomplished by the vocal tract configuration," Füstös said.

The researchers had to face several challenges as they worked to reconstruct the structure of the 5,300-year-old mummy's vocal tract.

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"We had to deal with Ötzi's position, whose arm is covering his throat," Avanzini told Discovery News. "For our project this is the worst position you can imagine. Moreover, the hyoid bone, or tongue-bone, was party absorbed and dislocated."

With special software, the researchers moved Ötzi's arm, repositioned his skull in the erect position, reconstructed his vertebrae, from the first one (C1) closest to the skull, to the first thoracic vertebra (T1), and reconstructed and repositioned the hyoid bone, which supports the tongue.

Rolando Füstös

They ended up with a complete model of the vocal tract, including the vocal cords and mouth, though they missed important data such as the tension and density of the vocal cords or the thickness and composition of the soft tissues that affect the human voice.

MRI scans would have helped the researchers getting more insights, but the technology could not be used because of the condition of Ötzi's mummified body.

"We had to rely on mathematical models and a software that simulates the way the vocal tract works," Cosi said.

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He explained that calculations of vocal area functions applied on the structure of the vocal tract produce a certain vocal sound.

"We ... tried to extract the formants of a synthesized sound 'injected' in the reconstructed vocal tract," Cosi said.

Taking into consideration that Ötzi had a rather large head and slender body, the researchers concluded that his voice likely had a fundamental frequency between 100 Hz and 150 Hz, in line with today's average male.

"This is a new, interesting aspect on Ötzi's research that deserves to be taken into consideration for further research," Albert Zink, director at the EURAC Institute for Mummies and the Iceman in Bolzano, told Discovery News.

Frank Rühli, director of the Institute of Evolutionary Medicine at the University of Zurich and president of the scientific advisory board of the Iceman, agreed.

"It is a novel high-tech approach to bring 'life' to ancient mummies. It helps to understand the impact of post-mortem processes on the preservation of anatomical sturcture," he told Discovery News.

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