The undersides of ferns have many looks.

But all these intricate structures do the same   thing.

They hold – and then  launch – the fern’s spores.

Spores are the main way ferns make more ferns, but  they’re not the eggs or sperm.

Those come later.

Since before the dinosaurs roamed  … and plants grew sex organs called   flowers … ferns have been “doing it”  through flying spores and swimming sperm.

When the spores mature, a fern leaf comes alive.

Look how things are moving under there.

Each of these clusters is called a sorus.

And every worm-like thingy is  a sporangium full of spores.

The sporangium has an outer ring filled  with water.

When it’s warm outside,   that water starts to evaporate.

The ring shrinks,  making the sporangium crack open.

The ring bends   farther and farther back.

The sporangium  jerks forward … and catapults the spores out.

A single fern launches millions of spores.

Each one grows into a gametophyte.

But these  pea-sized plants aren’t baby ferns.

Where their   fern parent was asexual, the gametophytes  make eggs and sperm in specialized organs.

Yep, fern sperm.

It’s a thing.

Look at these little curlicues.

When the rains come, sperm swim away from the  gametophyte that made them – a tiny puddle will   do.

They follow a trail of pheromones to  find eggs stored in nearby gametophytes.

When sperm meets egg, ta-da!

A fern sprouts  right out of its gametophyte mother,   which it feeds on.

Now, this  is a baby fern.

Finally.

Awww.

Ferns don’t need to wait around for some  insect to help them with pollination.

They can go it alone, as long as there’s water.

So, next time you go on a  walk through a damp forest,