Sierra Madre ground warbler

The Sierra Madre ground warbler (Robsonius thompsoni) is a bird species that was discovered on the Luzon Island in the Philippines by the University of Kansas research team. This new species is named after Max Thompson, a retired professor from Southwestern College and a research associate in the Biodiversity Institute at the University of Kansas.^[2][3] They feed on insects and tend to live in tropical understories. Some taxonomists continue to list the species in the Timaliidae, others in the Pellorneidae. Current studies suggest that it should be placed in the Locustellidae. They’re ground-walking songbirds — rotund, with strong legs and weak wings — and it appears that they can barely fly. They tend to inhabit dense forest understories, where they feed on insects. Their song is extremely high in pitched and ventriloquial — it is almost impossible to locate the source of the sound in the forest — they always sound like they are far away, even when they are almost at your feet. The bird looks similar to the other two species of ground warblers in the Philippines, the Bicol ground warbler and the Cordillera ground warbler, so it was not recognized as an independent species at first.^[4][5]

The three species of ground warblers are identical in size, shape and in juvenile plumage coloration, but they differ from one another in their adult plumage coloration, as discovered by University of Kansas biologist, Pete Hosner. Since they are so alike they were always thought to be the same species, until a DNA test was conducted where it became very obvious that these species were in-fact not the same.^[6] One way to tell the difference between a Bicol ground warbler or a Cordillera ground warbler and a Sierra Madre ground warbler is that the plumage of an adult bird is variegated brown, gray and red. The Sierra Madre ground warbler is also 20 centimeters long with relatively long legs.^[7]

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