Look at the underside of a fern leaf. Those rows of orange clusters aren’t tiny insects; they’re spores waiting to be catapulted away. Once a spore lands, it grows into a tiny plant, from which fern sperm swim away, searching for an egg to fertilize. Think of that next time you’re hiking in the forest.

Is There a Quick Fix for Ocean Acidification? :    • Is There a Quick Fix for Ocean Acidif...  

PBS EARTH MONTH PLAYLIST:    • Earth Month from PBS  

DEEP LOOK is an ultraHD (4K) short video series created by KQED in San Francisco and presented by PBS Digital Studios. See the unseen at the very edge of our visible world. Explore big scientific mysteries by going incredibly small.



Each of the clusters on the fern leaf is called a sorus. Within each sorus are wormlike structures called sporangia, which are filled with spores.

If you look at a sporangium under a microscope, you see it has an outer ring filled with water. When the spores mature and it’s warm outside, that water starts to evaporate. The ring shrinks and bends back, making the sporangium crack open. Then the ring jerks forward, hurling out the spores.

A single fern launches millions of spores. Each one grows into a tiny plant about as big as a pea, known as a gametophyte. But gametophytes aren’t baby ferns. Instead, their job is to make eggs and sperm in specialized organs. When it rains or the environment is moist, that’s when ferns mate: Fern sperm swim away on a film of water to find eggs to fertilize. The fertilized eggs then grow into ferns.

So, do ferns have seeds?

No, ferns don’t make seeds or flowers.

+ Find a transcript on KQED Science:

https://www.kqed.org/science/1992380/...

+ More great Deep Look episodes:

The Secret Lives of Plants playlist:
   • The Secret Lives of Plants | Deep Look  

Busy Bees and Other Pollinators playlist:
   • Busy Bees and Other Pollinators | Dee...  

+ Shoutout!

Congratulations to these ___ fans on our Deep Look Community Tab for correctly answering our GIF challenge!    • Post  

@hunterbrock3349
@lionparcelpalagan7515
@Ischemiaa
@leprifacioncustard4921
@markembeck7099

+ Thank you to our top Patreon supporters ($10+ per month)!

Burt Humburg
Max Paladino
Karen Reynolds
Daisuke Goto
Chris B Emrick
Wade Tregaskis
David Deshpande
Laurel Przybylski
Cristen Rasmussen
Mark Jobes
El Samuels
Carrie Mukaida
Cho Minsung
Jessica Hiraoka
Louis O'Neill
Elizabeth Ann Ditz
Noreen Herrington
Jeremiah Sullivan
Levi Cai
Drspaceman0
Titania Juang
Roberta K Wright
The Mighty X
R B
BulletproofFrog
Jellyman
Mehdi
吳怡彰
SueEllen McCann
KW
xkyoirre
wormy boi

+ Follow Deep Look and KQED Science on social:

  / deeplookofficial  
  / deeplook  
Instagram:   / kqedscience  
Twitter:   / kqedscience  


+ About KQED

KQED, an NPR and PBS member station in San Francisco, serves Northern California and beyond with a publicsupported alternative to commercial TV, radio and web media.

Funding for Deep Look is provided in part by PBS Digital Studios and the members of KQED.

#ferns