From Tony Brown
The feather-like projections on the back of the pre-dinosaur Longisquama insignis (24 March, p 8) remind me of a defensive feature of much later animals.
Could these “early feathers” have acted in a similar way to a porcupine’s quills? That could explain the thick border on one edge: to strengthen them. A would-be predator would probably leave with a mouth full of these “feathers” instead of the creature itself.
New Ollerton, Nottinghamshire, UK
