OG48-27

[邁向高等學府]

Until recently, scientists did not know of a close vertebrate(having a backbone) analogue to the extreme form of altruism observed in eusocial(真社會) insects like ants and bees, whereby (這麼一來) individuals cooperate, sometimes even sacrificing their own opportunities to survive and reproduce, for(表目的) the good of others(難句). However, such a vertebrate society may exist among underground colonies(group of animal) of the highly social rodent(嚙齒目動物) Heterocephalus glaber, the naked mole rat.(晏鼠)
請教一下紅色部分句子，
scientists did not know of a close vertebrate.....

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[agk99]

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