Flycatcher borders blur into warblers and thrushes
Old World flycatchers (Muscicapidae) are small songbirds of Europe, Africa, and Asia, with only scarce New World strays. John Fleming hung the Muscicapa family name in 1822. Ernst Hartert admitted by 1910 that walls between flycatchers, warblers, and thrushes refused to stay neat.
The family counts 357 species in 57 genera, according to the International Ornithologists' Union. Only two, the bluethroat and the northern wheatear, also breed in North America. The name Muscicapa joins the Latin words for fly and to catch, and Mathurin Jacques Brisson applied it to a genus in 1760, long before it labelled the family. Members range from the European robin and the nightingales to magpie-robins, whistling thrushes, stonechats and the Angola cave chat.
Hartert's answer to the muddle was to lump warblers, thrushes, babblers and monarchs into one giant family. Ernst Mayr and Dean Amadon revived the idea in 1951 with 1,460 so-called primitive insect eaters in eight subfamilies, and a committee after the 1954 Basel ornithological congress endorsed it. DNA hybridisation work by Charles Sibley and colleagues then showed those subfamilies were not close kin, so the group was broken apart. The American Ornithologists' Union finally split off the thrushes in 1998.
Genetics has kept reshuffling the roster. Whistling thrushes, shortwings and the alethes moved in from the thrush family after 2003, while the cochoas moved out. Studies in 2010 found that Muscicapa and two related genera were not natural groups, and a 2016 analysis covering 37 of 42 species in that tribe proposed new and revived genera. The family probably split from the thrushes in the early Miocene.
Most are 9 to 22 cm long, often drab brown, though males can be bright, with weak songs, harsh calls and broad flat bills for snatching insects in flight. They live wherever trees grow, up to Himalayan mountain woods, and northern species fly south in winter. Hole nesters average about eight eggs, compared with two to five for birds building open cups.
Source: Old World flycatcher
