Which has a longer tail, a mouse or a rat? - briefly
Rats possess tails that are proportionally longer than those of mice, often extending beyond the body length. In contrast, a mouse’s tail is shorter and generally equal to or slightly shorter than its body.
Which has a longer tail, a mouse or a rat? - in detail
Mice and rats belong to different genera within the family Muridae, and their tails differ markedly in absolute length and proportion to body size.
The common house mouse (Mus musculus) typically measures 7–10 cm in head‑body length. Its tail ranges from 7 cm to 10 cm, often matching or slightly exceeding the body length. Field mice (e.g., Apodemus spp.) show similar proportions, with tails generally 80–100 % of body length.
The Norway rat (Rattus norvegicus) and the black rat (Rattus rattus) are larger. Head‑body length averages 20–25 cm, while the tail extends 18–20 cm, sometimes reaching 22 cm. Consequently, the rat’s tail is longer in absolute terms and roughly 85–95 % of its body length.
Key comparative points:
- Absolute length: rat tail ≈ 18–22 cm; mouse tail ≈ 7–10 cm.
- Length‑to‑body ratio: mouse tail ≈ 1.0 × body length; rat tail ≈ 0.9 × body length.
- Species variation: some mouse species (e.g., deer mouse) have tails up to 12 cm; some rat subspecies possess tails slightly longer than body length.
- Sex and age: males often have marginally longer tails; juveniles exhibit proportionally shorter tails that elongate with growth.
- Environmental influence: arboreal species develop longer, more prehensile tails for balance, but within the common laboratory and wild strains, the above ranges hold.
Overall, the tail of a rat exceeds that of a mouse both in raw measurement and in most proportional assessments.