This is "宇宙の子どもたち" (Sora no Kodomotachi) which translates to "Children of the Universe"

This was used as the opening for Dinosaur King: Mesozoic Meltdown (Pterosaur Legends) (season 2) in Japan.
(It was called "Ancient Ruler Dinosaur King DKidz adventure: Pterosaur Legend" in Japan)

Thanks to umishi on Reddit for the translation.