Feeding on Buttercup pollen? Many similar beetles on neighbouring flowers.
No interactions present.
Rather aptly, the Swollen Thighed Beetle.
Chris Brooks - www.dragonfly-images.co.uk
My Flickr site - www.flickr.com/photos/ceb1298
I've seen it called the Fat-Thighed Beetle, and variations of the same.
Lat/Lng: 51.6645, -4.121
OS grid ref: SS534983
Pathside grassland amongst lakes of Wetlands and Wildlife Trust