What is true about coccygeal vertebrae in animals?

• A. It is variable depending on species and breed
• B. They are always seven
• C. They are fixed across all breeds
• D. They are always fused to the sacrum

Answer: (A)

Coccygeal vertebrae are the bones that form the tail region, and their number is not the same in every animal or breed. Different species have different tail lengths, and selective breeding within a species can further change how many tail vertebrae are present or how long the tail appears. Some animals have long tails with many coccygeal vertebrae, while others have short tails or are naturally tailless. The sacrum, a fixed block of fused vertebrae, is separate from the tail vertebrae, and the coccygeal bones are not universally fused to it. Because of these variations, saying the number is fixed, always seven, or always fused to the sacrum would be incorrect. The true point is that the coccygeal vertebrae count varies with species and breed.