having been locked in an arms race with snakes 在这个过程中

282. When paired with venom,
     再配上毒液
283. the effect can be deadly.
     效果致命
284. But mammals have acquired some extraordinary defenses...
     但是哺乳动物与蛇的军备竞赛 已经开展超过一亿年
285. having been locked in an arms race with snakes
     在这个过程中
286. for more than a hundred million years.
     哺乳动物获得了非凡的防御能力
287. The sidewinder snake.
     侧进蛇
288. It will wait for hours at a time for signs of passing heat.
     它会等待经过的热痕迹 一等就是几个小时

来自《我们星球上的生命 第一季 第五集 Life on Our Planet S01E05 巨兽阴影下》第 285 行