...while showing off their own. 同时炫耀自己的力量

129. He needs a territory of his own.
     它需要自己的领地
130. The two begin a ritual display.
     两只鸟开始了一场仪式性的展示
131. Assessing the other's strength...
     评估对方的力量
132. ...while showing off their own.
     同时炫耀自己的力量
133. Their coordinated moves
     它们协调一致的动作
134. as formal as a dance.
     像舞蹈一般正式
135. Who will be the first to back down?
     谁会率先退却？

来自《我们星球上的生命 第一季 第一集 Life on Our Planet S01E01 生命法则》第 132 行