Brief lives, ended

St Mark's flies only live a week or so, emerging in late April to mate and die.

Spiders are ultimate bondage experts that have been found to produce two sorts of glue: a strongly adhesive one that sticks webs to vertical surfaces in order to snare flying insects like these in unbreakable bonds, and a lightly adhesive version that attaches the silk to the ground but easily pulls free so that a creeping insect touching it becomes inextricably tangled in loose strands. How spiders manage to do this is not fully understood but scientists are trying to replicate the 'one glue, two strengths' strategy. See here.