Experts ask if there was a tsunami in ancient Orkney
A new academic paper has suggested it is possible neolithic mass burials in Orkney and Shetland contain the bodies of tsunami victims.
The authors said archaeologists should test remains to see if the bones show the distinctive signs of drowning in sea water.
Prof James Goff said the work was based on findings from the southern hemisphere.
It is published in the Journal of Archaeological Method and Theory.
Prof Goff, from the University of New South Wales, told BBC Radio Orkney there are sites in the Solomon Islands and Vanuatu where there are "known tsunamis that have happened in prehistory at the times that these mass burials date to".
He added: "We then looked for areas where there's not a lot of activity from earthquakes, or anything like that.
"And so Shetland and Orkney obviously come to mind because of the much earlier event, which was huge, the Storegga landslide."
The so-called mega-slide occurred more than 8,000 years ago off western Norway, and caused a tsunami which has left traces from Norway to Greenland, western Scotland, north east England and Denmark.
"When it comes around to more recent events, somewhere around just over 5,000 years ago, there's a sudden burst of mass burial sites being created," Prof Goff explained.
"The question is, is it at all possible that even a single body in there might have drowned? And, if so, when did that drowning take place?
"And is it indeed possible that it is indeed linked to the Garth tsunami?"
Sand left by that event has been discovered in peat layers at Garth Loch, South Nesting in Shetland, where sea levels appear to have risen by around 10m (33ft), though no traces of it have been discovered in Orkney.
Prof Goff is keen to stress he, and his co-authors, are not suggesting archaeologists have got it wrong.
"We are saying that this might be an extra little tool, if you wish, in the tool box that the archaeologists can use when they're examining a mass burial site in the islands," he said.
Initial reaction to the article from archaeologists who've excavated Orkney's neolithic sites has been sceptical.
They said the sites are sophisticated and show no signs of having been built in haste.
Others have described evidence for the thesis as "scanty".
They pointed out that the mass burials in Orkney appeared to have been spread out over hundreds of years, and are not all clustered around one single traumatic event.
Prof Goff accepts that there are "many questions" still to be answered. But he defended the paper as a new way of looking at the burial sites.
He said: "Even if one, or two, or three victims are found to have to have been the result of drownings from the sea then, of course, we're going to be asking the question 'Was that just someone who fell out of a boat and drowned?
"Or was it someone who was killed in a storm? Or do we have indications here of a tsunami?'"