Earliest spears

[Duncan Head]

 Rather earlier than we are used to, but they are weapons, and they're undeniably ancient:

The ancestors of humans were hunting with stone-tipped spears 500,000 years ago, according to a new study – around 200,000 years earlier than previously thought. This means that the technology must have been developed by an earlier species of human, the last common ancestor of both modern humans and Neanderthals.

The invention of stone-tipped spears was a significant point in human evolution, allowing our ancestors to kill animals more efficiently and have more regular access to meat, which they would have needed to feed ever-growing brains. "It's a more effective strategy which would have allowed early humans to have more regular access to meat and high-quality foods, which is related to increases in brain size, which we do see in the archaeological record of this time," said Jayne Wilkins, an archaeologist at the University of Toronto who took part in the latest research.

The technique needed to make stone-tipped spears, called hafting, would also have required humans to think and plan ahead: hafting is a multi-step manufacturing process that requires many different materials and skill to put them together in the right way. "It's telling us they're able to collect the appropriate raw materials, they're able to manufacture the right type of stone weapons, they're able to collect wooden shafts, they're able to haft the stone tools to the wooden shaft as a composite technology," said Michael Petraglia, a professor of human evolution and prehistory at the University of Oxford who was not involved in the research. "This is telling us that we're dealing with an ancestor who is very bright."

The use of spears for hunting has been dated back to at least 600,000 years ago, from sites in Germany, but the oldest spears are nothing more than sharpened sticks. The evidence for stone-tipped spears until now has been no more than 300,000 years old, from triangular stone tips found all over Africa, Europe and western Asia. "They're associated in Europe and Asia with Neanderthals and in Africa with humans and our nearest ancestors," said Wilkins. "Sometimes at these sites, they were used for other ways as well, sometimes for cutting or butchery or as knives or in processing hides or other materials."

To find out if any stone tips were being used on spears any earlier than that, Wilkins examined sharp stones found at a site called Kathu Pan, in the Northern Cape region of South Africa. The sediments in which these tips had been found had been previously dated to 500,000 years old but it was unclear if the stones themselves had ever been used for anything other than handheld purposes such as cutting or butchery.

Wilkins took close-up photographs and put the stones under a microscope to look for the tell-tale damage caused to stones whenever they are used on spears. "We know from experimental studies that, when a point is used as a spear tip, the concentration of damage is greater at the tip of the point than along the edges," she said. "That's the same pattern we saw in the Kathu Pan point."

Her analysis is published today in the journal Science. Dating the stone tips to 500,000 years ago means that they were used on spears by the last common ancestor of modern humans and Neanderthals, Homo heidelbergensis. The idea that Homo heidelbergensis developed stone-tipped tools made a lot of sense, said Petraglia, because Homo sapiens and Neanderthals, which descended and split from Homo heidelbergensis around 300,000-400,000 years ago, used similar stone-tipped spear weapons.

Petraglia added that there were several other implications to the discovery that Homo heidelbergensis had used hafting to make spears. Adding stones would not only have given our ancestors an easier way to kill prey, but also to do it from a distance. "There is a big difference between thrusting and throwing," he said. "You can kill from a distance, maybe 10 to 30 metres away. The previous ancestors did not have that technology, so it means you are now occupying a new ecological niche, you can now take animals down more efficiently."

Before Homo heidelbergensis, Homo erectus was known to have used handheld stones as cutting tools. But they were not using, as far as anyone knows, spears. "This is a major innovation, getting into a new ecological niche," said Petraglia.

He added that the discovery also shed light on the development of modern human cognition. "Hominins – both Homo erectus and earlier humans – were into this meat-eating niche and meat-eating is something that is thought to be very important in terms of fuelling a bigger brain," said Petraglia. "In terms of our evolutionary history, that's been going on for millions of years. You have selection for a bigger brain and that's an expensive tissue and that protein from meat is a very important fuel, essentially. If you become a killing machine, using spears, you've come up with a technological solution where you can be reliant on meat-eating constantly. Homo heidelbergensis is known as a big-brained hominid, so having reliable access to meat-eating is important."

From http://www.guardian.co.uk/science/2012/nov/15/stone-spear-early-human-species

[Patrick Waterson]

As a follow-up of sorts, we have this news article: http://www.bbc.co.uk/news/science-environment-23061016


Early humans evolved to throw about two millions years ago, according to new research.

Anatomy changes found in the extinct species Homo erectus allowed this ability to evolve.

Archaeological evidence suggests hunting intensified during this time, which scientists now attribute to the ability to throw.

Researchers tell the journal Nature that the ability helped early hunters to evolve and migrate around the globe.

The ability to throw at very high speeds is unique to humans. We can throw much faster than our closest living relative - the chimpanzee - which can only reach speeds of 20mph compared to 90mph that many professional athletes can reach.

To investigate the evolutionary development of the ability to throw, scientists first had to understand the biomechanics of throwing today.

Fastest motion

They recorded the throwing movements of college baseball players using motion capture cameras and observed that the shoulder acts like a slingshot as the arm rotates backwards.


The maximum shoulder rotation (pictured middle) is when elastic energy is able to power the throw


PW - The javelin does seem to have been a popular weapon among earlier human cultures.  In the old WRG army lists it was very hard to find an army without JLS somewhere in its ranks.

The ligaments and tendons surrounding the shoulder then stretch and store elastic energy, which powers the forward throw. When this energy is released it generates what scientists found was the fastest motion the human body produces.

Neil Roach, from George Washington University, US, who led the study, said that changes in the anatomy of hominins (early humans) that occurred two millions years ago, enabled energy storage in the shoulder that allowed fast throwing, and therefore hunting, to occur.

"Success at hunting allowed our ancestors to become part-time carnivores, eating more calorie-rich meat and fat and dramatically improving the quality of their diet.

"This dietary change led to seismic shifts in our ancestors' biology, allowing them to grow larger bodies, larger brains, and to have more children, and it also did interesting things to our social structure.

"We start to see the origins of divisions of labour around that time, where some would be hunting, others would be gathering new foods.

"It probably also allowed us to move to new environments, such as areas that did not have vegetation to support us before we had the ability to hunt," Dr Roach told BBC News.

He added that it was important to remember "that what we think about hunting and behaviour is still a hypothesis" and further studies were needed.

'Fascinating problem'

Another member of the research team, Daniel Lieberman from Harvard University, US, said the most fascinating finding for him was that half the power that humans generate from throwing comes from elastic energy stored in the shoulder.

"That's not a by-product of evolution for something else, it's clearly an adaptation. There were shifts in our anatomy that enabled us to throw accurately, so we want to understand better just what those early hunting challenges were.

Speaking to BBC News from Kenya he explained how, compared to the wildlife he was surrounded by - cheetahs, lions and leopards - humans had no natural weapons such as claws.

"Human hunting is such an fascinating problem and the fact that these features all appear by the time Homo erectus evolved, suggests that hunting may have been a selective force for the ability for throwing."

Prof Lieberman added that the next step was to discover what exactly early humans were using to hunt, as no weapons have been found from this time in the archaeological record.

PW - He probably means "exactly what early humans were using to throw," and the rock and throwing-stick, both of long use, both come to mind.

Other academics, perhaps predictably, demur.

Susan Larson from Stony Brook University, New York, was not involved in the research. Her work also focuses on the shoulder anatomies of primates and humans in order to study their evolution. She said it could be easy to over interpret what was significant from a fossil.

"We're looking at the same fossils, it's a question about how you interpret the anatomy that you see in those fossils.

"Homo erectus was not necessarily such a proficient thrower. I think [Dr Roach and colleagues] are discounting the combination of features of how the shoulder as a whole has to work.

"Their [Homo erectus] shoulder still functioned to give the hand a very wide range of motion in order to manipulate things and make tools, but it wasn't designed the same way as it is in humans.

"You cannot look at just one thing and say how a complicated piece of anatomy works, especially something like the shoulder. You have to understand how all parts work together to bring about a broad range of motion," Prof Larson told BBC News.

The new research introduces more of a strong theoretical model, than any definitive evidence of throwing behaviour in Homo erectus, said Jill Rhodes from Drew University, US.

"The humeral torsion - the angle at which the head of the humerus (top of the arm) is articulating at the shoulder joint - does not fall within the range of modern throwing athletes and more relevantly, as throwing is a one-handed behaviour, there is no evidence for asymmetry in the humeral torsion angle in Homo erectus.

"There simply is not the fossil preservation and without it, we cannot say that the humeral torsion demonstrated in that species is not an aspect of phylogeny rather than behaviour.

"This research opens a window into our understanding of past behaviour, but our view is still cloudy."

[Justin Taylor]

I don't know if fire hardened spears would precede stone?

http://en.wikipedia.org/wiki/Fire_hardening

Certainly I have made them in survival training - I don't think my stone chipping skills are up to much.

[Patrick Waterson]

They certainly outlasted stone: Herodotus, describing contingents in Xerxes' army (480 BC):

"The Libyans wore a dress of leather, and carried javelins made hard in the fire." - VIII.71

"The Mysians ... used as javelins staves with one end hardened in the fire" - VIII.74

It was another people who employed a resource that may conceivably have preceded either:

"The Ethiopians ... carried ... spears, the head of which was the sharpened horn of an antelope" - VIII.69

This arrangement does not require tools or fire, merely a suitable sapling for the shaft and a horn from a dead antelope for the 'warhead'.  Insert sapling end into horn base and one has what may be prototype spear Mark 1.  Adding binding or glue gives Mark 1a or 1b respectively.  In theory this arrangement could have preceded the use of fire and/or stone - not sure if it actually did, but worth a thought.

[Justin Taylor]

Well you would need something to sharpen the horn.

[Patrick Waterson]

A flat rock, maybe?

Another weapon possibility is bone, although this requires some means of fracturing the bone in such a way as to give a usable point of sufficient size, and durability is not a strong point.

[Erpingham]

Another weapon possibility is bone,

But first find your monolith ......