Not so long ago researchers thought that dinosaurs never saw grass. But then they discovered coprolite (a technical term for fossilised dung) that showed dinos had eaten grass.
A related myth to fall is Darwin’s abominable mystery or the genesis of flowering plants. He thought it was abominable because it bothered him. Neither he nor other evolutionists expected to find the seeds of angiosperms in early Cretaceous strata.
“75 different angiosperm taxa recovered from rich assemblages of angiosperm flowers, fruits and seeds in 11 mesofossil floras from eastern North America and Portugal, ranging in age from Barremian-Aptian to early or middle Albian, about 125–110 million years ago.”