Mousebird | ©Dr. Caesar Photography (Lake Naivasha, Kenya)
Mousebirds (order Coliiformes) are one of the perennial puzzles in bird systematics. They do not look or act much like any other birds. They are social fruit-eaters that dangle precariously at odd angles in tight clumps, feet spread wide and long tails often splayed. The six living species are all found in Sub-Saharan Africa.
They do belong in Hackett et al.’s “land bird clade,” with passerines, parrots, falcons, woodpeckers, the Coraciiformes (kingfishers, hornbills, bee-eaters, etc.), and others, but where within that very large assemblage they fall is so far still a perplexing mystery.
Their unique physiologies offer few clues, and so far, large-scale genetic studies have concluded that mousebirds’ “affinities … remain equivocal” (McCormack et al. 2012) and that their systematic position is “highly unstable” (Wang et al. 2011) across different types of analyses.