Looks like a Myxomycete, growing on the underside of a bracket fungus on fallen silver birch.
Caution: Do NOT use iSpot to identify fungi to eat!
Some fungi are very poisonous so a mistaken ID could have serious consequences.
No interactions present.
The black balls are but the yellow look too big.
All given ID's are subject to error/ommissions. Please seek independent verification before acting on ANY advice given. BE SAFE =)
The closeup is being deceptive. The black objects are the pores in the underside of the bracket, and the yellow-orange balls are about the right size for a Myxo.
Lat/Lng: 51.3694, 0.0212
OS grid ref: TQ407653