01 Verified
The blue whale is the largest animal known to have ever existed.
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“it is the largest animal known to have ever existed.”
Source: Blue whale, Wikipedia. Checked 2026-10-31.
Ocean Oddities
An 'immortal' jellyfish, a shark that lives for centuries, and a waterfall under the sea.
- 02 Verified
Greenland sharks may live between 272 and 510 years, longer than any other known vertebrate.
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“Greenland sharks have the longest lifespan of any known vertebrate, estimated to be between 272 and 510 years.”
Source: Greenland shark, Wikipedia. Checked 2026-10-31.
- 03 Verified
The 'immortal jellyfish' can, in theory, keep renewing itself indefinitely.
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“Theoretically, this process can go on indefinitely, effectively rendering the jellyfish biologically immortal, although in practice individuals can still die.”
Source: Turritopsis dohrnii, Wikipedia. Checked 2026-10-31.
- 04 Verified
Roughly half of Earth's oxygen production comes from the ocean.
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“Scientists estimate that roughly half of the oxygen production on Earth comes from the ocean.”
Source: How much oxygen comes from the ocean?, NOAA National Ocean Service. Checked 2026-10-31.
- 05 Verified
Only a tiny fraction of the ocean has been explored.
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“The ocean is vast, yet only a tiny fraction has been explored.”
Source: How much of the ocean have we explored?, NOAA National Ocean Service. Checked 2026-10-31.
- 06 Verified
Sea cucumbers breathe through their anus.
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“so that they "breathe" by drawing water in through the anus, extracting dissolved oxygen from water, and then expelling it.”
Source: Sea cucumber, Wikipedia. Checked 2026-10-31.
- 07 Disputed
Starfish were long thought to have no brain, but new evidence suggests their body may be 'all-brain'.
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“Traditionally, starfish were thought to lack a centralized brain. … Recent genetic evidence, however, suggests that the majority of an echinoderm's body is "all-brain".”
Source: Starfish, Wikipedia. Checked 2026-10-31.
- 08 Verified
Male seahorses carry the eggs until the babies are born.
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“The male carries the eggs for 9 to 45 days until the seahorses are released into the water fully developed, but very small.”
Source: Seahorse, Wikipedia. Checked 2026-10-31.
- 09 Verified
Snapping shrimp can stun fish with a blast of bubbles from their claw.
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“emitting an enormously powerful wave of bubbles capable of stunning larger fish and breaking small glass jars.”
Source: Alpheidae, Wikipedia. Checked 2026-10-31.
- 10 Verified
The Pacific Ocean is bigger than all of Earth's land put together.
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“larger than its entire land area combined”
Source: Pacific Ocean, Wikipedia. Checked 2026-10-31.
- 11 Verified
Underwater, the Denmark Strait has a 'waterfall' over three times the height of Angel Falls.
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“the Denmark Strait overflow would be the tallest waterfall in the world were it on land, with water falling over 3.5 km (2.2 mi); this descent is over three times the height of Angel Falls”
Source: Denmark Strait cataract, Wikipedia. Checked 2026-10-31.
- 12 Verified
There are lakes at the bottom of the sea, called brine pools.
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“A brine pool, sometimes called an underwater lake, deepwater lake or brine lake, is a volume of brine collected in a seafloor depression.”
Source: Brine pool, Wikipedia. Checked 2026-10-31.
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