only small creatures had made it... 只有小型生物才活了下来
thought to number only 3,000 in the wild. 据估在野外只有3000只
This is the only example of animals, 使用药物来挽救其他个体的生命
They thrust their venomous stings at their ancient rivals' only weak spot. 它们将毒刺 刺向它们古老对手的唯一弱点
...for they aren't the only giants of the Jurassic. 因为它们不是侏罗纪时代唯一的巨兽
As the plesiosaur can only eat so much, 因为蛇颈龙食量有限