So when they use their signature whistle they're advertising their identity to those around them as a way to maintain group cohesion.

所以当海豚使用标志性的哨音时，它们是在向周围的海豚宣传自己的身份，以此来保持群体凝聚力。

In Cairo, Hamas leaders held the second day of truce talks with Egyptian and Qatari mediators, with no apparent progress reported as the group maintained its demand.

在开罗，哈马斯领导人与埃及和卡塔尔调解员举行了第二天的停战谈判，但由于哈马斯坚持其要求，没有取得明显进展。