Short answers, pulled from the story.
A thrush is a member of the passerine bird family Turdidae, found worldwide. Thrushes are plump, soft-plumaged, small to medium-sized birds that live on the ground in wooded areas and feed on insects, other invertebrates, and fruit.
The thrush family Turdidae contains 194 species divided into 17 genera. The largest genus is Turdus, the typical thrushes, with 105 species, followed by Zoothera with 22 species and Geokichla with 21 species.
The great thrush is the largest thrush, weighing 128 to 175 g and measuring 28 to 33 cm. The Amami thrush might grow larger than the great thrush, while the larger blue whistling thrush is actually an Old World flycatcher.
Thrushes spread plant seeds by eating fruit and later regurgitating the seeds or passing them in their faeces, a process called ornithochory that has carried seeds across ocean barriers. Because some thrush populations migrate long distances, they disperse the seeds of endangered plants at new sites, reducing inbreeding and increasing the genetic diversity of local flora.
The French polymath Constantine Samuel Rafinesque introduced the family in 1815 under the name Turdinia. Molecular analysis places Turdidae as sister to the Old World flycatcher family Muscicapidae, the two having diverged in the Miocene around 17 million years ago.
Thrushes were once trapped and eaten across much of Europe, a practice now rare. They were cooked with polenta or grilled on a skewer in Italy, prepared with juniper berries in Belgium, and made into pâté or terrine, while Marie-Antoine Carême recommended cooking them in crépinettes with sauce Périgueux.