First-ever biomechanics study of Indigenous weapons shows what made them so deadly

For the first time, state-of-the-art biomechanics technology has allowed us to scientifically measure just how deadly are two iconic Aboriginal weapons.

In First Weapons, an ABC TV series aired last year, host Phil Breslin tested out a range of Indigenous Australian weapons. Amongst these were two striking weapons – the paired leangle and parrying shield, and the kodj.

Both weapons are used to strike at an opponent. While the warriors who wield them are well aware of the weapons’ lethality, our team was approached by the show’s creators, Blackfella Films, to use modern biomechanic tools and methods to assess them.

Our goal was to determine exactly where their striking power comes from and just what makes their ancient designs so deadly. Our study is now published in Scientific Reports.

Deadly weapons

We studied the kodj made by Nyoongar peoples of the southwest of the Australian continent and the leangle and parrying shield from the southeast.

The kodj is part hammer, part axe, and part poker. Its design is likely tens of thousands of years old, though determining exactly when this tool form was invented is difficult – only the stone parts can survive the archaeological record long term.

So far, the oldest axe recovered from an Australian archaeological site dates to between 49,000 and 44,000 years ago. It was found in a Bunuba site called Carpenter’s Gap 1.

The beauty of this weapon is its ability to be “pivoted by a turn of the wrist so that the blade can cut in any direction”.

The kodj used in our experiment was made by Larry Blight, a Menang Noongar man from Western Australia. Its handle is carved from wattle wood with a sharpened boya (stone) blade attached to one side and a blunt boya edge on the other with balga (Xanthorrhoea or grass tree) resin.

The leangle and parrying shield we studied were made by expert weapon-makers Brendan Kennedy and Trevor Kirby on Wadi Wadi Country. Each was carved from hardwood and are traditionally used together in one-on-one, close quarters combat.

Determining when this weapon was invented is even more difficult than the kodj, because both the leangle and its paired shield are entirely made of wood. Wood rarely survives long term, and certainly not over the thousands of years needed to track its innovation.

Currently, the oldest surviving wooden artefacts found on the Australian continent are 25 tools including boomerangs and digging sticks recovered from Wyrie Swamp, South Australia. They are more than 10,000 years old and only preserved because they were in a waterlogged environment which protected them from decay.

Biomechanics of the weapons

There are no previous studies describing human and weapon efficiency when striking with a hand-held weapon, so we were starting from scratch. For this study, the show’s host, Phil Breslin, acted as the warrior putting the weapons through their paces.

Using wearable instruments, we tracked the human and weapon kinetic energy and velocities built up during kodj and leangle strikes. Biomechanical analyses provided insights into shoulder, elbow and wrist motions, and the powers reached during each strike motion.

These tests found that the leangle is far more effective at delivering devastating blows to the human body than the kodj.

The kodj, on the other hand, is more efficient for an individual to manoeuvre, but still capable of delivering severe blows that can cause death.