I saw some honey dew produced by Oecophylla smaragdina on the branch after licking the bottom of the leafhopper. After careful observation, I found that there were two different kinds of gray butterfly larvae and a group of leafhoppers gathered together. Oecophylla smaragdina needs the excrement of grey butterfly larvae and leafhoppers. Oecophylla smaragdina is like a herder. They can enjoy sweet milk at any time.