Long-tailed finch
The long-tailed finch ("Poephila acuticauda") is a common species of estrildid finch found in Australia; also known as the blackheart finch, shaft-tail finch, Heck's grassfinch, Heck's grass finch, and Heck's finch. It is a predominantly fawn-coloured bird with a pale grey head and prominent black bib and eyes. It has an estimated global extent of occurrence of 1,000,000–10,000,000 km. It inhabits dry savannah habitats in Australia and adapts readily to aviculture. The IUCN has classified the species as being of least concern.
Medium ground finch
The medium ground finch ("Geospiza fortis") is a species of bird in the family Thraupidae. It is endemic to the Galapagos Islands. Its natural habitats are subtropical or tropical dry forests and subtropical or tropical dry shrubland. One of Darwin's finches, the species was the first which scientists have observed evolving in real-time.
In 1977, a severe drought reduced the supply of seeds in the Galapagos. The finch, which normally preferred small and soft seeds, was forced to turn to harder larger seeds. Subsequently, there has been a 10% change in the size of beak for these finches in a couple of generations.