Why did Nemo clown fish find their way home?

If you get lost in reality, can the "Finding Nemo" clown fish find home? It turns out, this colorful fish can sniff the leaves that fall into the sea from the island's forests near their coral reefs.

After hatching eggs, clown fish live in the open sea 10-20 days, possibly due to being swept away by ocean currents. But then, they will find a way to return to the coral reef where they were born. How these small fish remember the way to swim back is still a mystery.

Photo: LiveScience.

To understand this, scientists have looked at coral reefs surrounding the offshore islands in Papua New Guinea, southwestern Pacific. Here, clown fish and sea anemones - where the clown fish live - are particularly rich in shallow water beneath the forest canopy on the islands.

The team collected young clownfish that have returned to the recent reef. They took them to a lab on the boat and examined them with seawater lines of different smells - from an anemones bucket to the leaves of the forest on the island.

They found clownfish quickly swam to the smells of leaves and anemones, compared to other smells.

Danielle Dixson's team, from James Cook University in Townsville, Australia, also experimented on clownfish born and raised in aquariums, who have never lived on coral reefs or at sea. As a result, they are also attracted by the smell of anemones and anemones. This proves their preference is innate.

"This shows that you cannot separate the sea and the mainland environment, but always attach them to each other," Dixson said. "I will see if this is true for other fish."