Men may usually settle it over a drunken brawl in the pub or perhaps a verbal spat - but new evidence has shown for the first time that fighting over women in prehistoric times could have been worse than that.
A mass grave of skeletons investigated by Durham University-led researchers suggests that neighbouring tribes from prehistoric times were prepared to brutally kill their male rivals to secure their women.
The research, described in the academic journal Antiquity, focused on thirty four skeletons found buried in the village of Talheim in the south-west of Germany. Genetic evidence inferred from the skeletons' teeth suggests they were of people killed in an attack between rival tribes around 5000 BC.
The researchers found that, although there were adult females among the immigrant skeletons, within the local group of skeletons there were men and children only. They conclude the absence of local females indicates that they were spared execution and captured instead which may have indeed been the primary motivation for the attack.
Lead author Dr Alex Bentley from Durham University's Anthropology Department said: "It seems this community was specifically targeted, as could happen in a cycle of revenge between rival groups. Although resources and population were undoubtedly factors in central Europe around that time, women appear to be the immediate reason for the attack.
"Our analysis points to the local women being regarded as somehow special and were therefore kept alive."
The Durham University-led team, with researchers from University College London, University of Wisconsin and a German government body, came to their conclusions after analysing the strontium, carbon and oxygen isotopes signatures of the skeletons' teeth. These give vital information about the skeletons' geological origin and diet.
There have been many witness accounts of fighting over women in the last hundred years but most archaeological evidence points to violence erupting over resources, overcrowding and property. The archaeological findings from this study for the first time strongly suggest violence took place over mates as early as prehistoric times, according to the scientists.
The skeletons from the mass grave in Talheim, which were excavated in the 1980s, were all buried in a single pit of three metres long. The deliberateness of the prehistoric attack was first realised when German skeletal experts determined that the majority had been killed by a blow to the left side of the head, suggesting the victims were bound and killed, probably with a stone axe. Others may have been killed from arrow-wounds from behind as if the victims had tried to flee.
The research was funded primarily by the Leverhulme Trust, with support from the National Science Foundation.