This is the 9979th most frequent Russian word.
антарктической
"Antarctic" or "Antarctic-related."
In this sentence, 'антарктической' is used as an adjective to describe the type of fauna specific to Antarctica.
Я изучаю жизнь антарктической фауны.
I am studying the life of Antarctic fauna.
Here, 'антарктической' is part of a possessive construction to indicate that the observed phenomena belong to or are characteristic of Antarctica.
Во время экспедиции мы наблюдали удивительные антарктической природы явления.
During the expedition, we observed amazing phenomena of Antarctic nature.
In this example, 'антарктической' is used to describe the specific domain of science, emphasizing its focus on Antarctica.