Step 1: Understanding the Question:
The question asks for the animal group that falls outside the branch of zoology known as "Herpetology."
Step 2: Detailed Explanation:
• Definition of Herpetology: Herpetology is the study of amphibians (frogs, toads, salamanders) and reptiles (snakes, lizards, turtles, crocodiles).
• Analysis of Options:
- Turtles (A) and Snakes (D): These are reptiles, so they are studied in herpetology.
- Frogs (B): These are amphibians, so they are studied in herpetology.
- Avis (C): This is the Latin class name for "Birds." The study of birds is known as "Ornithology."
• Conclusion: Birds are vertebrate animals but they are biologically distinct from "herps" (amphibians and reptiles) and have their own specialized field of study.
Step 3: Final Answer:
Herpetology does not study about Birds (Avis).