After about thousands of years into its existence, one of the oldest trees in the United Kingdom has astounded scientist by undergoing "sex change."

Fortingall Yew is a heritage tree, situated in the Highland Perthshire village of Fortingall, is described to be about 3,000 and 5,000 years. The tree is known to be male which has small spherical structures that produce pollen. Female yews sprout bright red berries.

Yet recently, the ancient yew amazed the scientists when three red berries were seen on its branches which suggest that it had become a female. The berries are now being examined and their seeds will be included in a project to conserve the genetic diversity of yew trees.

"Odd as it may seem, yews, and many other conifers that have separate sexes, have been observed to switch sex," said Max Coleman of the Royal Botanic Garden in Edinburgh who found the berries.

"Normally this switch occurs on part of the crown rather than the entire tree changing sex. In the Fortingall Yew it seems that one small branch in the outer part of the crown has switched and now behaves as female." Coleman added.

Numerous tree species contain both male and female parts however a few species like the holly or yew, are normally just male or female. A few species, such as ash, routinely switch sex, creating male flower one year and female fruits another. In the event that a tree creates a crop of seeds one year, it may switch the following year to male flowers to decrease the strain on itself.

Coleman had sown the three berries on a pot. If they reproduce, the Fortingall yew will bear its first identifiable breed in perhaps thousands of years.

The tree is now surrounded by a wall, having lost its center and one side years ago.