A Remote Lake Sealed Off Since the Ice Age Became Home to Millions of Jellyfish Found Nowhere Else on Earth
The Daily Galaxy • • science
Key Points:
- Jellyfish Lake in Palau's Rock Islands is a unique marine lake isolated for around 12,000 years, harboring millions of golden jellyfish that have evolved into a distinct subspecies found nowhere else.
- The lake formed after the last ice age when rising sea levels cut it off from the ocean, creating a closed ecosystem with stable conditions that allowed species like the golden jellyfish to dominate.
- The golden jellyfish exhibit a distinctive daily migration pattern driven by sunlight, swimming east at sunrise and west as the sun moves, facilitating a symbiotic relationship with photosynthetic algae living in their tissues.
- This symbiosis allows the jellyfish to provide sunlight to the algae, which in turn supply energy and nutrients to the jellyfish, sustaining both the species and the lake's ecosystem.
- Jellyfish populations have fluctuated due to climate events like El Niño, which disrupt water temperatures and algae growth; a significant decline led to a temporary closure of the lake, but the population has since shown signs of recovery.
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