Ferns are among the most amazing species on the planet.
During a recent walk at Brooker Creek Preserve, I spotted multiple species. With the help of my Seek app (iNaturalist), I added to my growing knowledge of the world of ferns. I know some people may like the world of beer, but I would rather be in the world of ferns any day of the week. With 124 known native ferns, Florida has more species than anywhere else in the U.S. outside Hawaii or Puerto Rico.
Ferns are one of the oldest groups of plants on Earth, with a fossil record dating back to the middle Devonian (383-393 million years ago) (Taylor, Taylor, and Krings, 2009). Recent divergence time estimates suggest they may be even older, possibly having first evolved as far back as 430 mya (Testo and Sundue, 2016). According to Jerald Pinson, “Despite the venerable age of the group as a whole, most of the earliest ferns have since gone extinct. Groups like the Rhacophytales, which were possibly some of the earliest progenitors of ferns, the ancient tree ferns Pseudosporochnales and Tempskya, and the small, bush-like Stauropterids have all long ago disappeared. The diversity of ferns we see today evolved relatively recently in geologic time, many of them in only the last 70 million years.”
Oliver Sacks, one of my mentors, is best known as an explorer of the human mind, a neurologist with a gift for the complex, insightful portrayals of people and their conditions that fuel the phenomenal success of his books. He was also a card-carrying member of the American Fern Society and since childhood had been fascinated by these primitive plants and their ability to survive and adapt. The best-selling author of Awakenings and The Man Who Mistook His Wife for a Hat carried his ceaseless curiosity and eye for the wondrous to the province of Oaxaca, Mexico to explore ferns and detailed it in in his book Oaxaca Journal (OliverSacks.com). Having read his journal many years ago, it appears to have gained purchase in my mind. I now seek to learn more about fern morphology, phylogenetic relationships, the fern lifecycle, and the important role gametophytes play in the biology of ferns.
Today, ferns are the second-most diverse group of vascular plants on Earth, outnumbered only by flowering plants. “With around 10,500 living species, ferns outnumber the remaining non-flowering vascular plants (the lycophytes and gymnosperms) by a factor of 4 to 1. How did ferns become so diverse, and what are the secrets to their success?” Pinson writes. “What traits do they share in common, and how are they different from other groups of plants?
I have included here a few samples from Brooker Creek and other locations.
Thanks to Jerald Pinson from the American Fern Society.
Where can see the amazing ferns of Florida?
Get out into The Great Florida Outdoors!!
Dr. Norman is an advanced master naturalist graduate of the FMNP program from UF and a board-certified dermatologist based in Tampa and Riverview. He can be reached at 813-880-7546.
Photo caption above: Golden Polypody fern (Phlebodium aureum)