In his attempt to categorize the Middle English dialogues, debates and catechisms, Frances Lee Utley distinguishes between five bird debates (Utley 1972:716 ff.), i.e.:
In addition to that, we have some more Middle Scots debates presenting birds as anthropomorphized representatives of human opponents, among others William Dunbar's The Merle and the Nightingale (late 15th century).
Some of these bird debates have a well-defined topic, others deal with a large variety of subjects. However, love is a major topic in all of them. Some have a decision by a third party in the end, with some the resolution is evident, and others are obviously irresolvable or the verdict is transferred to the audience.
Taking into consideration the dates of composition from c1200 to the late 15th century, this text form appears to have been a favorite among Middle English poets.