There is no scientific consensus on what was on the menu of the first dinosaurs. Some paleontologists believe that early dinosaurs were carnivorous, while others believe they were herbivorous. There is evidence to support both theories, but the truth may be more complex. It is possible that early dinosaurs were omnivores, eating both plants and animals.

One piece of evidence that supports the theory that early dinosaurs were carnivores is the fact that they had sharp teeth. These teeth would have been well-suited for tearing through flesh. Additionally, some early dinosaurs have been found with fossilized remains of other animals in their stomachs.

On the other hand, there is also evidence that supports the theory that early dinosaurs were herbivorous. Some early dinosaurs have been found with fossilized remains of plants in their stomachs. Additionally, some early dinosaurs had teeth that were better suited for grinding plants than tearing through flesh.

It is possible that the diet of early dinosaurs varied depending on the species. Some dinosaurs may have been primarily carnivorous, while others may have been primarily herbivorous. Additionally, the diet of early dinosaurs may have changed over time as they evolved.

Ultimately, the question of what was on the menu of the first dinosaurs is still a mystery. However, the evidence that exists suggests that they may have been both carnivorous and herbivorous.