
And once more, we get to thank the globe-trekking Jackie Chambers for today's photograph and write-up! Jackie writes:
I came across this fantastic ‘fiber ball’ on the beach while doing field work in southeastern Spain. The balls, or aegagropiles, are actually composed of the fibrous remains of Posidonia oceanica. Over time, dead fibrous tissue of individuals of this species are tossed about by waves. The constant rolling action of the sea eventually forms this material into balls which wash up on the beach.
Sea grass, or Neptune grass, is a flowering plant adapted to live underwater. It is native to the Mediterranean Sea where it forms large undersea meadows (see meadow photograph on this page). It has strap-like leaves which can be 1cm wide, and can reach up to 1m long. The species produces green flowers, and the fruit is sometimes called the “Olive of the Sea” (photograph via Forum Natura Mediterraneo). Like many true aquatics, it is the movement of the water that ensures the pollination and seed dispersal of this interesting plant.
For photos of the plant structure, clearly showing the live green leaves, the fibrous remains of old leaf sheaths, the rhizomatous root, an aegagropile, as well as flowers and fruits, see this detailed article (in French).
Posidonia oceanica is ecologically important as it provides habitat for a wealth of underwater creatures and plays a key role in the health of underwater ecosystems. Neptune grass is often called the “Lungs of the Mediterranean Sea”. Habitat destruction and pollution are threatening these populations.





I recall seeing something similar at a little museum in B.C.: balls of pine needles tossed about in a river/creek/stream. Fascinating!
Amazing, simply amazing and many thanks to all who share and make our days brighter!
Everyday, I learn something new or see something beautiful on this page. What a wondrous world we live in and don't even see. Even this tiny ball of grass is a marvel to behold.
Also somewhat reminiscent of dung beetle balls.
fuzzy..?....is that you...?
This is great to see and read about. Having grown up on the the ocean off the barrer reel Island called Plum Island, in Newburyport Massachusetts. I appreicate learning of other parts of the world.
As a child we often played with ocean plants that would wash up on the beach. After hurricanes many things from far away would show up also.
Thank you,
Margaret-Rae
My compliments to the handler on a well maintained cuticle.
ti's an amazement
the under water photos are
good-i use the zoom icon on
the computer to fill the screen
with the images thank you
i used to live in the north and
remember the beaches-fondly
i live in florida we worry abut ours
the under life and the coral reefs
It is an informative site and I love it for reasearch!
Wow, I'm soooo happy to see this!!! I collected some of these from the beaches of Crete many years' ago, because I thought they were unusual and beautiful. Always wondered what they were/where they came from & didn't really know how to go about finding out. Now I know!
Thank you very, very, very much Daniel and Jackie, you've solved a mystery for me. Ahhhhhh.....
I'm jumping in a bit late here, but I was wondering if anyone had any further information about these claims. It says "scientists", but I was unable to locate any peer-reviewed sources for that in a cursory search. Any help here?
Posidonia fanclub - we saw some on a beach in Sardinia this year and Clare met them off the South of France and is in love with them. So much that she's standing here speechless (very unusual for Clare!). We have a posidonia resting against the keyboard and think its amazing. Rob? posting above - we also took photos of a dung beetle rolling his ball of dung. We still can't believe it's the action of the sea that forms such a perfect sphere.
Thanks a lot for this information. It was a kind of a miracle for me, really couldn't imagine what these little balls on the beach of Sardegna could be. But now I know :-))