along.

Hi, I'm Kate and this is MinuteEarth.

We've known for… well, for a long time that animals often move pollen from flower

to flower, fertilizing plants.

All sorts of critters pollinate all sorts of plants, but as far as scientists knew,

this process only happened on land – or at least above the water.

But in 2016, researchers discovered that animal pollination also happens underwater.

Itty-bitty crustaceans and worms visit certain species of seagrasses and seaweed.

They pick up the sticky, mucus-y pollen – or spermatia, basically a seaweed's version of

pollen – and ferry them, sometimes over considerable distances, to the seagrass's

and seaweed's female reproductive organs.

The details are really cool, but they aren't actually what I find most interesting about

this discovery.

What blows my mind is that, despite scientists knowing for a long time that animal pollination

is an important and really common process above the water – I mean, a full 80 percent

of plants are pollinated by animals!

– we're just now realizing that it's also happening underwater.

There are a bunch of different reasons for this gap in our knowledge.

First, the physics of animal pollination underwater seemed pretty unlikely.

Seawater is almost 800 times denser than air, and it's often in motion; it didn't seem

like animals small enough to pollinate the tiny flowers that exist underwater would be

able to move easily between them.

Also, the timeline didn't seem to fit; many species of aquatic plants and seaweeds existed

long before animal pollination is thought to have evolved.

So scientists assumed that the only way pollen moved around underwater was via the motion

of the ocean itself.

As a result, nobody was really looking underwater for evidence of animal pollination.

And it isn't exactly an easy process to simply stumble across, seeing as it happens

at night, on a tiny scale – many of these pollinators are no bigger than the tip of

a pencil.

It took a few very observant, very open-minded researchers to figure out that aquatic animals

can – and do – act as pollinators.

And in some ways, this discovery isn't actually that big a deal; most of the pollination of

these seagrasses and seaweeds – and most underwater pollination in general – probably

does happen via the motion of water.

So at least ecologically, underwater animal pollination is probably a relatively minor

phenomenon.

But the fact that it exists at all is a big deal, because it upended what was basically

scientific dogma, and forced scientists to take another look at some of their underlying

assumptions.

These tiny pollen-toting critters are a reminder that science is done by humans, and what seems

logical to humans isn't necessarily how the world actually works… nature can still

surprise us.

If you've got a nature lover in your life, you'll definitely want to head over to our

MinuteEarth store.

Right now, we're making waves with our fall merch sale – we're not squidding around

about these holiday discounts!

We've got all sorts of great science gifts, like this holographic bioluminescent sea creatures

sticker set; perfect for a notebook, a laptop, or a water bottle!

And we've also got a book that answers all your most pressing science questions, a serengeti

pin set, science posters, nerdy shirts and more.

Click the link in the description to dive into a shop that's perfect for fueling curiosity.