Question

1. Working outside is very hard for the people in Antarctica.
2. Working outside is very hard for the people of Antarctica.
[Can we use both prepositions, 'in' and 'of'?]

3. They study sea animals in Antarctica.
4. They study sea animals of Antarctica.
[Can we use both prepositions, 'in' and 'of'?]

Answer 1

Yes, you can use both prepositions, but they don't mean exactly the same thing. Do you understand the differences?

Answer 2

What differences do they have?

Answer 3

The differences are very slight. I'll vary the sentences a bit so you can tell the difference easily. (These differences don't matter when referring to Antarctica since there have never been indigenous human populations there.)

<i>1. Working outside is very hard for the people in Alaska.
2. Working outside is very hard for the people of Alaska.</i>
#1 refers to people who are in Alaska, working hard, no matter where those people came from.
#2 refers to people who are indigenous to Alaska.

<i>3. They study sea animals in Australia.
4. They study sea animals of Australia.</i>
#3 refers to people who study sea animals, no matter where those animals came from.
#4 refers to people who study only species that are native to Australia.

In referring to Antarctica, the differences between these two prepositions in these particular sentences is practically non-existent. But if you put other geographical areas in place of "Antarctica," the differences are clearer.