Final answer:
Most theropods were carnivorous, with diverse feeding strategies, from predation to opportunistic scavenging, as seen in T. rex, to insectivory and arboreal lifestyles in smaller theropods like cynodonts.
Step-by-step explanation:
When considering theropods outside the genera Baryonyx or Spinosaurus, a key word that characterizes some aspects of their ecology is carnivory. Most theropods were carnivorous, hunting and consuming other animals to survive. For instance, the Tyrannosaurus rex, one of the most famous theropods, is often debated as either a predator or scavenger. Its enormous jaws and teeth suggest adaptations for powerful biting, while its relatively short forelimbs might imply a scavenging lifestyle. However, new evidence proposes T. rex could not run fast due to its hip structure, indicating it was possibly more of an opportunistic feeder. Meanwhile, other theropods, like the nocturnal and insectivorous cynodonts, show a completely different ecological niche. They lived a life contrasting with the larger, more predacious theropods by being small and arboreal. This diversity in feeding strategies and lifestyles reflects the wide ecological roles theropods filled during their reign in the Mesozoic Era.