Who is bigger: a rat or a squirrel? - briefly
Squirrels exceed rats in overall size, possessing a longer body and greater average weight. Consequently, a squirrel is larger than a rat.
Who is bigger: a rat or a squirrel? - in detail
Rats and squirrels differ markedly in body dimensions. Adult brown rats (Rattus norvegicus) typically reach a body length of 20–25 cm, with the tail adding another 15–20 cm. Their mass ranges from 250 g to 500 g, occasionally exceeding 600 g in well‑fed individuals.
Tree squirrels, such as the eastern gray squirrel (Sciurus carolinensis), have a body length of 20–25 cm, but their bushy tails extend 15–20 cm, giving a total length of 35–45 cm. Average weight falls between 400 g and 600 g, with some species (e.g., red squirrel, Sciurus vulgaris) staying near 250 g, while larger ground squirrels (e.g., prairie dog relatives) can surpass 1 kg.
Key comparative points:
- Length: Both groups share similar head‑body measurements; squirrels gain extra length from their tails.
- Weight: Most squirrels outweigh average rats; the gap widens for larger squirrel species.
- Body shape: Rats possess a more compact, cylindrical torso; squirrels exhibit a leaner build with a prominent tail for balance.
- Sexual dimorphism: Male rats are slightly larger than females; in many squirrel species, males are marginally heavier, but the difference is modest.
Geographic and environmental factors influence size. Rats living in urban settings often exhibit higher body mass due to abundant food, while squirrels in colder regions may develop larger bodies for thermoregulation.
Overall, when comparing typical adult specimens, squirrels generally achieve greater total length and higher body mass than rats. Exceptions occur only in unusually large rat populations or very small squirrel species.