Read any good bones lately?

Visiting biological anthropologist Jill Rhodes has, and they may provide some of the earliest evidence of when modern humans started doing something that would have been a pivotal development in the evolution of hunting and warfaresomething we all take for granted.

What’s the crucial development? The overhead throw.

New research by Rhodes and Steven E. Churchill of Duke University published in the Journal of Human Evolution addresses the question of when human hunters added long-range projectile weapons (those thrown overhead) to their arsenal and whether this was a hunting method also employed by Neandertals of the time.

“We were able to use analyses of the humerus bone (upper limb) to show that early humans in Europe were possibly using projectile weapons as early as the Middle Upper Paleolithic period and that Neandertals did not have or habitually use this form of technology,” says Rhodes.

Rhodes’ research calls on recent studies in the field of sports medicine that indicate that individuals who engage in habitual overhead throwing, like baseball pitchers, have increased humeral retroversion angles in their throwing arms and a greater degree of bilateral asymmetry in retroversion angles than do non-throwers.

In other words, if someone forcefully throws overhand a lot and from an early agebe it a spear or a baseballit’s going to leave a signature on the throwing arm that won’t be seen on the non-throwing arm.

While their sample sizes were small, Rhodes did find tell-tale signs of the use of overhead projectile use in the bones of the human remains they studied but not in the Neandertal remains.

“There’s not a lot we can say definitely, but there are a lot of interesting hints about what might have been going on,” says Rhodes. “Archaeologically, we don’t really have a lot of information as to the origins of projectile technology, but the osteological record does point to the use of projectile spear use by early humans at this time and not by Neandertals.”

Rhodes is hesitant to make too much out of their findings but acknowledges that there are interesting implications for those who wonder why humans prospered and Neandertals died out.

“There are implications about the efficiency of hunting for the two species. When you are thrusting a spear, you’re basically an ambush hunter and have to hide behind cover and jump out and stab your prey at short range. Whereas if you have projectile technology, you can remain at a safe distance where you won’t scare your prey and you will increase your efficiency, effectiveness and your kill rate,” says Rhodes.

Rhodes points out that the use of projectile weapons by humans at this time may have been especially advantageous as it would have coincided with the warming of Europe and the opening up of forests.

“If the forests aren’t as dense, you don’t have as many opportunities to hide and ambush prey,” explains Rhodes.

Rhodes has been studying how the use of different weapons imprints itself on the skeleton ever since her days as a Ph.D. student at The University of Bradford in the United Kingdom, when she identified a biomechanical signature associated with long-bow use among soldiers who fought in the War of the Roses.

She is currently the principle osteologist on the archaeological investigations in the Coastal Zone of Jalisco (Mexico) project, where she works with student assistants in applied bioarchaeology and funerary archaeology.

“Material culture is great, but when I want to know what the people were doing, it makes sense to me to go to the people and essentially read their skeletons,” says Rhodes.