I am voting to close as homework question.
I felt like I would give you a few hints though.
> is it possible for other animals to live without us?
Life on earth have existed for almost 4 billions years. Animals have existed for about 600 millions years. Modern human (AMHS) have existed for 0.2 million years.
> Do humans have a huge impact on the ecosystem?
Here are just a few pictures taken by airplane of agricultural lands
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and a koala searching its home after a rapid man-made deforestation
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