Mesozoic era
69 years old.
Cenozoic Era
I know that the angiosperms were most dominant during the cretaceous period but im not too sure about the dinosaurs dominant era. I would assume they were both dominant in the same era but I am not 100% sure.
Canadian Arctic
I know that the angiosperms were most dominant during the cretaceous period but im not too sure about the dinosaurs dominant era. I would assume they were both dominant in the same era but I am not 100% sure.Read more: http://wiki.answers.com/Dinosaurs_and_angiosperms_were_dominant_lineages_during_with_geologic_era#ixzz1G5bqBpQR
Dinosaurs
Jellyfish intervirbrates
The Mesozoic Era
cycads
They were dominant during the mesozoic era, which was made up of the Triassic, Jurassic, and Cretaceous periods.
The dominant organisms in the Mesozoic Era were dinosaurs, which ruled the land, along with marine reptiles and ammonites in the oceans. In the later part of the era, mammals and birds began to diversify and emerge as important groups of organisms.
Tonic-dominant harmony