... this behavior of children is what scientists once considered uniquely human. but there is more and more evidence that some animals use symbolic tools in much the same way. shumaker would see great apes in times of great stress or sadness, like a female who had an infant that died.

두가지 질문있습니다.
1. 여기에서 in many를 쓰면 안되나요 ??왜 in much를 쓰게되었는지 알려주세요.

2. who와 that은 관계대명사라하는데, 한 문장안에 관계대명사 두개가 올수 있나요 ???

정확하고 자세한 답변 부탁드리겠습니다. ^^