Is the steppe mouse smaller than the common mouse? - briefly
The steppe mouse (Apodemus uralensis) usually reaches 6–9 cm in head‑body length, compared with 7–10 cm for the common house mouse (Mus musculus). Consequently, it is generally marginally smaller.
Is the steppe mouse smaller than the common mouse? - in detail
The steppe mouse (Apodemus agrarius) typically measures 65–85 mm in head‑body length, with a tail of 70–95 mm and a mass of 12–20 g. The common house mouse (Mus musculus) averages 70–95 mm in head‑body length, a tail of 70–100 mm, and a weight of 15–30 g.
- Head‑body length: steppe mouse 65–85 mm; house mouse 70–95 mm.
- Tail length: steppe mouse 70–95 mm; house mouse 70–100 mm.
- Body mass: steppe mouse 12–20 g; house mouse 15–30 g.
These data indicate that the steppe mouse is generally smaller, especially in body mass, although tail length overlaps. Morphologically, the steppe mouse possesses a more streamlined skull and shorter rostrum, adaptations to arid grassland habitats, whereas the house mouse shows a broader skull suited to omnivorous diets in human‑associated environments.
In summary, comparative measurements demonstrate that the steppe mouse is, on average, smaller than the typical house mouse, with the most pronounced difference in body weight.