By Shaun Smillie
They are the weapons of a 64 000-year-old hunting scene in KwaZulu-Natal - quartz segments that still carry the traces of blood and tissue of the prey.
What that prey was has been lost to time, but the evidence of the kill is what Dr Marlize Lombard can see when she peers into her laboratory microscope.
There is a reddish-brown blob of animal tissue, white bone fragments still clinging to the stone-age tool, and there is the coppery tinge of a prehistoric blood smear, 64-millennia old.
This forms part of the evidence that has enabled a team of South African scientists to deduce the quartz segments are the earliest-known examples of stone-arrow heads.
This, at a time when mammoths and Neanderthals still roamed Europe.
The team's findings were published last week in the journal Antiquity.
The tools were excavated in Sibudu Cave, near Ballito, and the possible presence of such technology in the deep stone age, is making academics reassess just how complicated and modern-human-like our ancestors really were.
These arrow heads could be at least 2 000 years older than a bone arrow that was discovered at the cave, two years ago.
"It is like piecing together a crime scene and we were following multiple lines of evidence," says Lombard, who uses the jargon of a modern-day forensic investigator.
Lombard, an archaeologist at the University of Johannesburg, and other members of the research team have been able to replicate these impact fractures, using-modern day replicas of bows and spears and thrusting them into carcasses of wildebeest and other game.
But it is not just blood and animal tissue Lombard found on the tools; she also observed the remains of what the team believe is gum-based resin, used to glue the tips to the shafts.
It is the use of this prehistoric glue that would have required following a recipe and intricate multi-staged planning that has academics wondering.
Lombard said manufacturing such bows and arrows would have demanded a high level of cognitive reasoning and thought to understand how to make rope and know how to tie a good strong knot.
"We are convinced they were or were at least similar to us cognitively and behaved like us too," says Lombard."
What Lombard cannot tell is whose blood is on the arrow heads, but other researchers working at the cave have drawn up a list of likely suspects.
"We have come across blue duiker, bush pig and buffalo," explains Lombard.
The presence of yellowwood shows that the environment then was wetter, but colder and the makers of those stone-tipped arrows would have hunted in a forest.