Ologies with Alie Ward

Episode: Pteridology (FERNS) with Fay-Wei Li
Date: December 3, 2025
Host: Alie Ward
Guest: Dr. Fay-Wei Li, Associate Professor at Cornell's Boyce Thompson Institute, pteridologist, author of Lessons in Survival from the Earth's Most Adaptable Plants

Overview

This episode dives into the world of ferns—ancient, adaptive, and often misunderstood plants—through the expertise and charm of Dr. Fay-Wei Li, a leading pteridologist (fern scientist). From the basics of fern biology to wild stories about Lady Gaga ferns, invasive species, and the mathematical mysteries of fractals and DNA, the discussion is a whirlwind of science, history, and fern fanaticism. Listener questions explore everything from fern sex lives to culinary tips, conservation, and culture.

Main Themes and Key Insights

1. What Makes a Fern a Fern?

• Definition by Reproduction: Ferns don’t have seeds or flowers. What truly sets them apart is a unique life cycle featuring two independent generations:

  • The diploid sporophyte (the usual leafy fern we know)
  • The haploid gametophyte, a tiny, independent organism where sex actually happens
    (06:27) "The most definitive way to define a fern is their sex life." – Dr. Li

• Life Cycle Details:

  • The fern fronds produce spores (not seeds), visible as powdery brown spots (sori) on undersides of leaves.
  • Spores germinate into gametophytes, which look like little green hearts or oven mitts, and can self-fertilize or outcross if multiple gametophytes are nearby.
    (07:46) "They basically have two independent generations, the haploid phase and the diploid phase." – Dr. Li

• Basic Anatomy: Rhizomes as stems, true roots, fronds as leaves.
  (08:14) "Textbook ferns will have a horizontal rhizome...leaf...roots." – Dr. Li

2. Where to Find Ferns: Surprises and Biodiversity

• Desert Ferns: Fern diversity in deserts is unexpectedly high, with "resurrection ferns" that can lose up to 90% of their water and bounce back with moisture.
  (04:14) "The most exciting place in North America to find ferns is in the desert...Arizona, for example, has one of the highest fern diversity." – Dr. Li

• Taiwan and New Zealand:

  • Taiwan, Dr. Li’s homeland, boasts double the fern species of the entire U.S.
    (09:59) "Taiwan has 800 fern species...the whole North America has only 400 species."
  • New Zealand’s silver fern is a national icon, and the region’s isolation fuels unique species.
    (44:03) "New Zealand...They have so many cool ferns."

3. Research, Discovery, and Fern Fame

• Herbarium Science: Old pressed fern specimens yield DNA, locality info, and even new species/genus discoveries.
  (11:20) "Herbarium is like a library of dead plants...we can get DNA from specimens over 100 years old."

• Naming Ferns & Lady Gaga: When discovering a new genus, Dr. Li’s lab named it Gaga (after Lady Gaga), partly inspired by both the plant’s genetics and Gaga’s inclusive message.
  (12:41) "One time we discovered a new genus and...decided to name it after Lady Gaga. So the genus is called Gaga."

4. Fern Genetics: The Most Extra

• Genome Insanity: Some fern species, such as Ophioglossum reticulatum, have up to 1400 chromosomes and 160 billion base pairs—vastly more than humans.
  (16:50) “This fern species has 160 billion letters...a lot bigger than a human genome. Why?...That’s something I want to figure out.” – Dr. Li

5. Evolutionary Saga

• Ancient Yet Youthful:
  • Ferns dominated prehistoric forests, contributed to coal formation, adapted after flowering plants arrived, and re-diversified in new niches.
    (18:32) “Ferns are both really old and also really young...they went understory and flourished...most lineages we see today are actually younger than flowering plants.” – Dr. Li

6. Fern Eating & Toxicology

• Human and Animal Interactions:

  • Not all fiddleheads (young fronds) are edible—some are toxic. In North America, stick to ostrich ferns (Matteuccia struthiopteris).
    (20:49) “Not all fiddleheads are edible. Some are toxic and carcinogenic.”

  • Most animals avoid eating ferns; they have few insect pests due to potent natural insecticides, some of which have been engineered into crops (corn) for pest resistance.
    (22:04) "Ferns are also very famous for having very little herbivory...the new generation of corn is super resistant..."

7. Ferns in Culture, Art, and the Plant Trend-verse

• Staghorn Fern Craze: Mounted, antler-like ferns have sold for up to $300,000 in Asia.
  (28:02) “...recently in Taiwan, there was a new variety of staghorn ferns that was sold over US$300,000.”

• Boston Ferns & Between Two Ferns: Boston ferns are the world’s most popular houseplant ferns, even starring on the set of “Between Two Ferns.”
  (24:35) “Boston ferns are...the most widely cultivated ferns in the entire world.”

• Fern Society: Fern fans are notably enthusiastic and tight-knit; Dr. Li is president-elect of the American Fern Society.
  (28:39) "In a botanical world, the fern people have the reputations of being really rowdy and just like all stick to each other."

8. Problems: Conservation, Invasion, and Research Funding

• Endangered Ferns: Over-collection and habitat loss threaten unique species like Florida’s "green hen" (Crested Polypody). Reintroduction efforts are in progress for some, e.g., American Hart’s Tongue fern.
  (29:44) “There are a lot of endangered fern species...overcollection...and the drainage of swamps also didn’t help.”

• Invasive Ferns: Some, like the Old World climbing fern in Florida and floating ferns (Salvinia molesta), are ecologically destructive.
  (46:03) “There are several really nasty ferns. So there's one species called Lygodium microphyllum, native in Asia, but in Florida, is killing forests.”

• Climate and Funding: Loss of habitats, changing climate, and especially lack of research funding are urgent issues facing botanists.
  (65:42) “Funding has been more and more difficult...Some fern research can really change things...We do really need to understand their diversity before they disappear.”

Notable Quotes & Memorable Moments

• (06:27) “The most definitive way to define a fern is their sex life.” – Dr. Li
• (12:41) "One time we discovered a new genus and...decided to name it after Lady Gaga. So the genus is called Gaga." – Dr. Li
• (19:46) "We call them diversifying in the shadow of angiosperms, in the shadow of flowering plants." – Dr. Li
• (22:04) "Ferns are also very famous for having very little herbivory. So you go out, right, go on a hike, look at all the fern fronds, they're usually intact...ferns, they are toxic for reasons they don't want to be eaten." – Dr. Li
• (27:32) "Staghorn ferns...a new variety was sold over US$300,000." – Dr. Li
• (28:39) "In a botanical world, the fern people have the reputations of being really rowdy and just like all stick to each other." – Dr. Li
• (65:42) “Funding has been more and more difficult...We do really need to understand their diversity before they disappear.” – Dr. Li

Listener Questions / Rapid-fire Segments

Growing ferns from spores (38:56)

• Dr. Li: For best results, sow spores immediately on moist substrate and maintain high humidity; viability varies by species.

Evolutionary longevity & survival strategies (41:04)

• Fern spores can colonize remote places rapidly due to being hermaphroditic; they can self-fertilize and start new populations.

Cultural significance in New Zealand (44:03)

• Silver ferns are a pervasive symbol, appearing on currency, uniforms, and national insignia.

Invasive and weedy ferns (46:03)

• Old world climbing fern in Florida and Salvinia molesta globally are ecologically problematic.

Ant ferns and symbiosis (49:12)

• Some ferns host ants in specialized rhizomes, gaining protection in a mutualistic relationship.

Fractals and math (55:05)

• Fern fronds show fractal patterns and Fibonacci spirals—to save space and as a result of shoot modification, a mathematically efficient growth strategy.

Houseplant troubles & tips (approx. 57:00)

• Ferns want humidity, indirect light, and soil that's kept moist but not soggy; Boston ferns are famous for dying on people!

Fern tattoos? (58:04)

• Dr. Li has none, but Lady Gaga fern would be his hypothetical choice.

Fern scent & taste (60:44)

• Hay-scented ferns are notable for fragrance; polypody “sugar rhizome” species taste like licorice!

Movement: Not ferns! (62:23)

• Sensitive plants (mimosa) respond to touch, not ferns, though their leaf shape leads to confusion.

Favorite fern? (60:21)

• Dr. Li: "I cannot answer that question. It’s like, who's your favorite child?"

Fern field guides/books (63:17)

• Plug for Dr. Li’s own book: Lessons in Survival from Earth's Most Adaptable Plants, and Emily Sessa’s new field guide.

The best part of being a fern scientist (67:00)

• Discovery, collaborating with colleagues, and the joy of the plant-obsessed community.

Timestamps for Important Segments

• 03:42 – Introduction of Dr. Fay-Wei Li
• 05:32 – The odd sex life of ferns
• 08:14 – Anatomy: roots, rhizomes, fronds
• 09:59 – Biodiversity: Taiwan and global fern diversity
• 11:20 – Herbarium magic & naming the Gaga genus
• 16:50 – Fern genome madness
• 18:19 – Fossil history & evolutionary adaptation
• 20:24 – Edible (and dangerous) fiddleheads
• 22:04 – Ferns’ natural pest resistance & crop GMOs
• 24:35 – Boston ferns in culture
• 27:32 – Pricey staghorn fern craze
• 29:44 – Endangered ferns and conservation
• 38:56 – Listener Q: Growing ferns from spores
• 41:04 – Evolutionary secrets to fern survival
• 44:03 – New Zealand fern culture
• 46:03 – Nasty invasive ferns
• 49:12 – Ant ferns and plant-animal symbiosis
• 53:51 – How tree ferns grow trunks
• 55:05 – Mathematical fractals in ferns
• 57:00 – Houseplant fern troubleshooting
• 60:21 – What’s the prettiest fern?
• 63:17 – Best fern books and field guides
• 65:42 – Challenges: funding and conservation
• 67:00 – The joy of discovery and fern community

Closing Thoughts

This episode beautifully weaves scientific insight with personal passion, showcasing ferns as evolutionary marvels full of mystery, utility, and beauty. Dr. Li's infectious enthusiasm is perfectly matched to Alie Ward's humor and curiosity, making the science both accessible and irresistible.

Links & Resources

• Dr. Fay-Wei Li’s book: Lessons in Survival from Earth's Most Adaptable Plants
• American Fern Society: Connect with fellow fern lovers!
• Further reading: Field guide by Emily Sessa (New York Botanical Garden)
• Ologies smallogies feed: Kid-friendly cuts of the episode

In short: Ferns are weird, old, young, resilient, hard to kill (in the wild), weirdly easy to kill (in your house), occasionally absurdly valuable, and totally fascinating!