The Smallest Mammal: Etruscan Shrew (Suncus etruscus)

The Etruscan shrew, scientifically known as Suncus etruscus, holds the title of the world's smallest mammal by mass. Weighing a mere¹ 1.2–2.7 grams (about the weight of a dime) and measuring 3.6–5.3 cm in body length (excluding the tail), this tiny creature is found in warm regions of Southern Europe, North Africa, and parts of Asia.

Despite its size, the Etruscan shrew has an incredibly high metabolism², requiring it to eat 1.5–2 times its body weight daily—primarily insects, larvae³, and small invertebrates⁴. Its heart beats at an astonishing 1,500 beats per minute, one of the fastest among animals. To sustain energy, it alternates between short bursts of activity and rest.

This shrew's small size poses challenges, such as rapid heat loss due to a high surface-area-to-volume ratio, forcing it to live in warm climates. Its diminutive⁵ stature⁶ also makes it vulnerable to predators⁷ like birds and reptiles⁸. However, its agility⁹ and nocturnal habits aid survival.

中文版：最小的哺乳动物——伊特鲁里亚鼩鼱（Suncus etruscus）

伊特鲁里亚鼩鼱（学名：Suncus etruscus）是现存质量最小的哺乳动物，体重仅1.2–2.7克（约一枚硬币的重量），体长3.6–5.3厘米（不含尾巴）。它分布于南欧、北非和亚洲部分地区的温暖地带。

虽然体型极小，但它的新陈代谢极高，每天需摄入自身重量1.5–2倍的食物，主要以昆虫、幼虫和小型无脊椎动物为食。其心跳速度高达每分钟1500次，居动物界前列。为了维持能量，它会在短暂活动与休息间切换。

娇小的体型导致其散热极快（体表体积比高），因此仅栖息于温暖地区。它也容易成为鸟类、爬行动物的猎物，但依靠敏捷性和夜行性习性生存。

Fun Fact: 它的脑占体重比例高达4%，高于人类（约2%），但智力水平仍待研究。