but a mere youngster. 但尚年少

184. ...adaptations that protect them and their young
     这些适应性可以保护它们及幼崽
185. from any would-be predators.
     免受任何潜在捕食者的伤害
186. A Smilodon...
     一只刃齿虎
187. but a mere youngster.
     但尚年少
188. He's not a serious threat...
     即便有匕♥首♥一般的牙齿
189. ...even with his dagger-like teeth.
     但它仍不构成严重威胁
190. He's never seen a Doedicurus up close,
     它从未如此近距离见过巨犰狳

来自《我们星球上的生命 第一季 第七集 Life on Our Planet S01E07 地球继承者》第 187 行