At the bottom are two fronds (under clear contact paper) showing variability. |
Resurrection Fern
Polypodium polypodioides
This tiny fern has always been a favorite of mine. It grows in an epiphytic fashion, anchoring
its wiry roots into the bark of trees with deep fissures, and receiving
nourishment from the water and dust in the atmosphere using energy from the sun
via photosynthesis. The fronds of this fern are fairly small, but
I’ve seen some that grow up to 3 or 4 inches.
It’s called the resurrection fern because it has an
adaptation that allows it to transform from a withered brown cluster of curled
leaves to a vibrant unfurled green frond.
This adaptation allows it to survive long periods of drought until the rains
come, which is helpful in south Florida, with our dry fall-winter-spring and
our rainy summers. Scientists tell us
that resurrection fern can stand up to a 95% water loss without perishing. Compare that to humans, who often find a 15% water
loss a fatal event.
The curled, dry fronds, waiting for water. |
I learned that this feat is possible because of a protein called
dehydrin. Dehydrin allows the cell walls in the leaf to
fold when drying, in a way that can be reversed without damage. As the fern dries, it manufactures dehydrin,
turns brown, and stops photosynthesis. When
moisture is available, the fern takes water in through its stomata
(tiny openings on the bottoms of leaves that allow for gas exchange), turns
green, and begins photosynthesis once again.
I’d always thought of it as native to tropical Florida. Imagine my surprise to find out that these
ferns range from Florida to Delaware and then west to Texas! Not only is it native to the Americas, but it’s
also native to Africa.
A complex ecosystem in a small space. |
This ink and watercolor study is of a live oak branch that
fell to the ground after a rainstorm.
The branch broke into several smallish chunks, so perhaps it was
insect-damaged; my experience with oaks is that the wood is very strong. I loved the interplay of texture and colors in
this tiny universe of lichens, mosses, bark and fern. Once again, sketching a subject led me to ask
questions and then to start
researching.
Needless to say, scientists are studying the property of dehydrins, which
could have many applications. Did you
know that resurrection fern has gone into space? It was the subject of a 1997 experiment on board
the space shuttle Discovery. To read more about this fascinating plant,
visit the hyperlinks within the text or listed below.
As always, thanks for visiting!
The sketch was done in my:
Aquabee Super Deluxe
spiral-bound sketchbook
9x6 in, (22.86 x 15.24 cm), 93 lb. paper
Sakura Micron Pigma pen 01,
Daniel Smith watercolors.
9x6 in, (22.86 x 15.24 cm), 93 lb. paper
Sakura Micron Pigma pen 01,
Daniel Smith watercolors.
Resources:
Wikipedia on
resurrection fern
Time lapse YouTube video of resurrection
fern coming back to life
Wikipedia
on dehydrin
No comments:
Post a Comment