Spring is in the air, a new season of life begins and while the birds and the bees are busy, it’s only natural for thoughts to turn to matters of fertility. And despite spending far too much time cooped up in laboratories, peering through microscopes in the pure pursuit of knowledge, even scientists aren’t entirely immune to thoughts of how adult creatures make more little creatures.

It’s appropriate then, that marine biologists have been studying precisely which aquatic species produces the most young, and with up to 2,000 babies to bear at once depending on the species, it used to be assumed for many years that male seahorses were the reigning champions. When it’s time to give birth, the males expel all 2,000 live young from their brood pouches in a constant stream, looking for all the world like living confetti cannons. But despite this impressive display, scientists have confirmed that an exponentially larger contender has actually captured the crown for “world’s most prolific spawner” – the ocean sunfish.

Weighing in at over 5,000lbs (or 2,268 kilos), the ocean sunfish is one of the ocean’s most bizarre-looking fish, resembling a gigantic swimming head as it swims awkwardly through the world’s temperate and tropical waters. Because it is actually listed as a vulnerable species by the International Union for the Conservation of Nature, scientists were amazed to discover that female sunfish actually pump out more than 300 million eggs over the course of a single spawning season.

The reason for this astonishing number is because the tiny eggs only have a very, very small chance of survival out in the open ocean due to a huge number of hostile factors including predation. In fact in a stable population, each adult replaces itself, so those 300 million eggs would only normally be expected to produce two adult sunfish.

So as the world's heaviest bony fish with the potential to carry 300 million new lives, this is definitely one expectant mother you'd give up your seat on the bus for...

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