Hoatzin

The present day Hoatzin has a bright blue face, tall head feathers, spots on its neck, and large feet for gripping tree branches. The future Hoatzin does not have a blue face, but a brown one to blend in with the future grasses and shrubs. It could also have shorter head feathers, so it can blend in better. It might lose it spots as well, due to it spending more time on the ground and not needing to blend into trees. In the future, it would also have longer legs with smaller feet, better for running since there might be less trees in the future. The hoatzin will also have a smaller body size, better for running and staying hidden in the brush.