The "learned insect" Kestrel refers to is, of course, Archy the Cockroach, one of the "contributors" to Don Marquis's newspaper column in the early parts of the 20th century.
Archy was a free-verse poet in New York who, upon his untimely death in 1916, was reincarnated as a cockroach. He would then climb onto Marquis's typewriter at the New York Sun newspaper and hurl himself from key to key, typing out poems and reports of life "from the underside." He's another of Kestrel's literary forebears...though he was more bug than bear, actually.