1. The relationship between the ants and the aphids is coenogenetic, as they rely on each other for survival.

蚂蚁和蚜虫之间的关系是共生的，它们相互依存以保证生存。

2. The coenogenetic bond between the birds and the crocodile ensures the birds get a meal while the crocodile gets its teeth cleaned.

鸟和鳄鱼之间的共生联系确保了鸟类有饭吃，同时鳄鱼也能得到牙齿的清洁。