Modern and extinct emu.
The modern Emu (centre) and King Island Emu (right) with human outline shown approximately to scale. Apart from obvious size differences, there were reports of colour differences between these emu taxa.
Date 2011
Source Heupink TH, Huynen L, Lambert DM (2011) Ancient DNA Suggests Dwarf and ‘Giant’ Emu Are Conspecific. PLoS ONE 6(4): e18728. doi:10.1371/journal.pone.0018728
Author Tim H. Heupink, Leon Huynen, David M. Lambert
Source: https://commons.wikimedia.org/wiki/File:Emu_size.png

The King Island emu (Dromaius novaehollandiae minor) is an extinct subspecies of emu that was endemic to King Island, which is situated in the Bass Strait between mainland Australia and Tasmania. The small size of the King Island emu may be an example of insular dwarfism.