Toothy clues to ancient farming practices in Scotland
Studies of teeth from sheep and cattle have provided new insights into farming practices in the Iron Age through to the Late Norse periods in Scotland.
Archaeologists used a range of techniques to determine the age, diet and health of livestock raised at two sites in Orkney.
One of the sites, Earl's Bu, appears to have been organised and managed as a large estate farm.
It may have been run this way from an earlier time than previously thought.
The study, which involved excavated animal remains and the examination of other historical evidence, could give fresh insights into ancient farming elsewhere.
The University of the Highlands and Islands, which did the research, said these other places could include other Scottish islands and Scandinavia.
The archaeologists said the good condition of the livestock at Earl's Bu gave an "overall impression" of an organised system of pastoral farming on the land.
Herds of sheep and cattle were pastured and fattened up in established fields or upland areas, they said.
This suggests that an elite group of people controlled the land in the form of manorial estates from the Viking period onwards.
The archaeologists said that this challenged the view of agriculture in the 9th to 11th Century being "dominated by free peasant farmers with varying degrees of obligation to chieftains and larger farmers".