A new study has found that ancient humans may have heard nature sounds a lot more distinctively than modern day humans.
• Field experts explain why ancient humans needed superior hearing and what used it for.
• Description of the tests conducted for the study.
• Results of the tests and their implications.
A team of researchers from Binghamton University (New York) are saying that ancient humans had superior hearing abilities and may have been better at distinguishing between sounds such as wind breezing or birds chirping.
Field experts speculate that ancient humans may have needed to be able to pick up on certain frequencies in order to communicate short range in an open environment.
Rolf Quam, lead researcher and field expert from Binghamton University, and his colleagues came to this conclusion after looking at various skulls and ear bones belonging to several specimens of Paranthropus Robustus and Australopithecus Africanus, long dead human ancestors who roamed the Earth somewhere between one (1) million and three (3) million years ago.
They also looked at some skulls and ear bones belonging to modern day humans and chimpanzees in order to be able to compare the hearing abilities of ancient specimens to those pf modern specimens.
The research team started the project by using computerized tomography scans (CT scans) to reconstruct the internal anatomy of the ears sported by Paranthropus Robustus and Australopithecus Africanus human. They also made virtual computer reconstructions of them by taking into consideration the data collected from available fossils.
The next step of the experiment involved adding a set of anatomical measurements to a computer model in order to predict the hearing abilities of the ancient humans. Since the number of fossils that had their inner ear bones intact was limited, Quam and his team focus mainly on the ancient humans from South Africa.
The results showed that not only did ancient humans have sensitivity range that was similar to that of chimpanzees, but that it was also slightly moved towards that of modern day humans. What this means is that they could hear better chimps.
A paragraph from the study reads as follows: “Compared with chimpanzees, both early hominin taxa show a heightened sensitivity to frequencies between 1.5 and 3.5 kHz and an occupied band of maximum sensitivity that is shifted toward slightly higher frequencies”.
And Quam also gave a statement to Live Science explaining that the difference between chimps and ancient humans, while small, may have helped the latter group communicate better in open environments like the African savannah.
While earlier studies have found that ancient humans used to live in forests, as well as savannahs, Quam gave another statement to Reuters stressing that the hearing discovery he and his team made may have come in handy in the savannah environment especially.
He explained that sound waves travel a lot further in rainforests than they do in savannahs.
Image Source: nbcnews.com