Solitaryspecies - such as tigers, domestic cats and rhinos - have less grey matter, the scientists found.
独处型的物种，例如老虎、家养的猫、以及犀牛，它们的脑里具有更少的灰质。
2
It didn't used to be so solitary, but humans introduced goats to the island, which ate every other member of its species.
本来，她还不至于如此孤单，可自从人类在该岛上引入山羊，她的所有同伴就被吃了个精光。
3
Only in the mid-20th century was it realized that the light brown solitary desert-dwelling insect was the same species as the red and yellow locusts of the plagues.