DARWIN'S BARBERRY : Berberis darwinii
This is an attractive shrub found widely around West Dunbartonshire, but it is an introduced plant. While not quite naturalised, it nevertheless has a tendency to merge with native species. You will often see it planted in in gardens including those in public spaces as it is very hardy. It is not considered a poblem here, but it is classed as invasive in New Zealand. Perhaps the climate and conditions are similar to that of its origins.
Introduced to not, it is loved by our wildlife such as bees and bumble bees. It is edible, but its thorns deter some browsers.
It was discovered in South America in 1835 by Charles Darwin during the voyage of the Beagle. and named after him. The berries are known to have been eaten by the early people there.
WIKIPEDIA : https://en.wikipedia.org/wiki/Berberis_darwinii