World problems

Title
Extinct species of Petalonamae
Extinct species of Desmostylia
Extinct species of Asiadelphia
Extinct species of Thecodontia
Extinct species of Titanoptera
Extinct species of Graptolites
Extinct species of Ornithopoda
Extinct species of Eurypterida
Extinct species of Placodontia
Extinct species of Tuarangiida
Extinct species of Conulariida
Extinct species of Stegosauria
Extinct species of Edestiformes
Extinct species of Lepospondyli
Extinct species of Kazacharthra
Extinct species of Caloneurodea
Extinct species of Bactritoidea
Extinct species of Ankylosauria
Extinct species of Condylarthra
Extinct species of Archaeoptera
Extinct species of Triconodonta
Extinct species of Gansuiformes
Extinct species of Hippuritoida
Extinct species of Corumbellata
Extinct species of Ornithischia