This project grew from a love for all things green and a budding interest in old natural history illustrations.

 

The daily posts are loosely presented in phylogenetic order. That is, it begins with the broad groups that appear earliest in the fossil record and proceeds in order of relationships. To make things manageable, I’ve focused primarily on land plants, but make a brief foray into algae at the outset before moving on to their terrestrial cousins. Although most modern species evolved relatively recently, bryophytes are the oldest type of plant that we have unequivocal evidence for in the fossil record, followed by lycophytes, ferns, gymnosperms, and flowering plants. As we’ll see, however, these are only the plant lineages that have survived to the present. There are menagerie of mysterious and spectacular forms that winked into and out of existence long before the species we’re familiar with ever came to be.

 

I’ve attempted to align the number of plants highlighted in each group with their proportional diversity. Recent estimates indicate there are some 400,000 known species of land plants. Of these, flowering plants make up the bulk of diversity with 364,000, followed by bryophytes with 22,000, then ferns with 11,800, lycophytes with 1,200, and gymnosperms trailing in last place with around 1,000 species. By dint of diversity, flowering plants will receive the most focus, with the number of posts for gymnosperms and spore-bearing plants roughly proportional to the number of living species.

 

Sprinkled throughout are poems and quotes that capture the spirit of botanical inquiry and wonder.

 

You can find attribution and links to the artwork and poetry on the corresponding information page available here: https://jeraldpinson.com/400-plants-info/ 

 

 

Illustration of Cladophora flavescens, with long green filaments and clearly demarcated cells walls.
Cladophora

Day 1 of 400. Cladophora. Green algae are best known for giving rise to land plants, but they have a diverse and venerable #NaturalHistory of their own that goes back ~ 1 billion years.

Illustration of Chara fragilis with a view of a leaf and a close up of the reproductive structures.
Charophytes

Day 2 of 400. Charophytes are incredible! These algae coat their surfaces with calcium carbonate, essentially making them the photosynthetic version of a mollusk. Their spiral egg casings are common components of the fossil record.

Illustration of Pleurococcus, with views of several different types of cells, including those encased in a layer of mucus beneath a branch.
Pleurococcus

Day 3. Algae are everywhere — in oceans, lakes, rivers, even in other organisms, such as lichens. The terrestrial alga Pleurococcus grows on trees by covering itself in a layer of mucous to avoid drying out.

Illustration of volvox algae with a poem titled "Bloom" by Elizabeth Halliday Walker

Marchantia

Day 4. Welcome to the wonderful world of byrophytes! #Liverworts have undoubtedly the coolest reproductive structures, with dainty male and female umbrellas perched on pendulous stalks and gemmae cups that disperse baby liverwort clones.

What's in a name

Day 5.“Mosses are so little known by the general public that only a few have been given common names...but I like the scientific names, because they are as beautiful and intricate as the plants..." -Robin Wall Kimmerer

Sphagnum

Day 6. The humble sphagnum is one of the most ecologically important plant groups on Earth. It stores 20X its weight in water and secretes acids that prevent decomposition, forming stratified bogs that hold ~1/3 of all carbon on land.

Dung moss

Day 7. Splachnaceae mosses are a bit macabre. They thrive in nitrogen-rich environments, including animal droppings, old bones, & rotting carcasses. Many also enlist the aid of flies for spore dispersal by enticing them with pungent scents and brightly-colored sporophytes.

Humbacked elves

Day 8. Buxbaumia mosses, called humpbacked elves, have microscopic gametophytes and large, uniquely shaped sporophytes. At least one species loses its leaves entirely at full maturity. This confused early naturalists to the extent they were initially thought to be fungi.

Tardigrade taxi

Day 9. Many mosses, such as Ceratodon purpureus, emit scents similar to those produced by flowers, and for the same purpose. Small microarthopods, like tardigrades, are attracted to these scents and help taxi moss sperm to fragrant female gametophytes.

An illustration of Phaeroceros carolinianus by Dianne Emery depicting the gametophyte and the spiraled horns, which rupture along their margins to release the spores. Used with permission.
Horns & feet

Day 10. Phaeoceros has hornlike structures that rupture with changes in humidity, releasing the spores within. Gametophytes that grow from these spores are called feet, which often have just one chloroplast per cell. Illustration courtesy of Dianne Emery.

Pohlia nutans

Day 11. Seed-free plants have swimming sperm that make precarious voyages through standing water from one gametophyte to another. The sperm of Pohlia nutans have been shown to live for days in temps above 140 degrees F.

Schistidium rivulare

Day 12. There are just 2 vascular plant species in Antarctica but more than 100 bryophyte species. Of these, Schistidium is the most diverse, with some growing on the continent through the Pleistocene. S. rivulare can survive for more than a year at temps of -80 degrees C.

Illustration of Syntrichia ruralis, with close up of leaf cell structure.
Life under a rock

Day 13. Syntrichia mosses have awnings that extend from the tips of their leaves to collect and funnel moisture. S. caninervis can be found growing under translucent rocks in the desert, where light can be reduced to just 1.2% of ambient, but relative humidity is doubled.

Fix illustrations of bryophyte capsules
Moss teeth

Day 14. How do #mosses release their spores? Many of their sporophytes have a dainty hat called an operculum, which falls off to reveal concentric rows of lamprey-like teeth that open and close with changes in humidity, exposing the spores within to wind currents.

Illustration of Dicranum flagellare
Snail glue

Day 15. Many mosses reproduce via vegetative budding, but these buds are larger than spores, making dispersal a challenge. Enter the humble slug, whose mucus adheres to and ensnares moss buds, carrying them a short distance before depositing them in their slime trails.

Illustration of Tayloria
Coprophagous symbiosis

Day 16. In 2013, a new species of dung moss, Tayloria octoblepharum, was discovered growing on the lid of a coprophagous pitcher plant in Borneo. Both get their nutrition from tree shrews, which defecate in the pitchers.

Illustration of Phascum
Moss & stone

Day 17. "There is an ancient conversation going on between mosses and rocks, poetry to be sure. About light and shadow and the drift of continents. This is what has been called the 'dialect of moss on stone' - an interface of immensity and minuteness, of past and present, softness and hardness, stillness and vibrancy, yin and yan." - Robin Wall Kimmerer

Dragon's gold

Day 18: Dragon's gold. S. pennata grows in dark corners of caves and grottoes. Its protonema have a layer of lens-shaped cells that concentrate the feeble light and reflect back a faint glimmer of mossy green, giving it the appearance of glowing in the dark.

Poem "I wonder if I will miss the moss" by Jane Mead

Illustration of fissidens brachypus
Epizoic

Day 19. You've heard of algae growing on slow-moving sloths. Many mosses are also adept an growing on animals, including beetles, millipedes, lizards, and turtles. F. brachypus grows on a single species of freshwater coral in the Amazon River.

Creating community

Day 20. “One gram of moss from the forest floor, a piece about the size of a muffin, [can] harbour 150,000 protozoa, 132,000 tardigrades, 3,000 springtails, 800 rotifers, 500 nematodes, 400 mites, and 200 fly larvae." -Robin Wall Kimmerer

Illustration of hypnum cupressiforme
Sun flecks

Day 21. Moss gametophytes don't have stomata, which allow other plants to breathe in CO2 and exhale O2, relying instead on diffusion through their cells. This makes them susceptible to drying out, but it also more efficient at gathering light. Research suggests H. cupressiforme can reach 50% of max photosynthesis in just 90 s while harvesting flecks of light on sun-dappled forest floors.

Illustration of Sphagnum squarrosum
Will-o'-the-wisp

Day 22. Strange lights have been seen emanating from bogs throughout history, eerie tendrils of bluish flame that were often interpreted as ghosts or malicious sprites. The lights are caused by the spontaneous, chemically induced ignition of methane, the product of decaying plant matter in peatlands.

Illustration of Polytrichum juniperum
Splash zone

Day 23. Some mosses, such as the Polytrichum juniperum depicted here, construct membraneous walls around their antheridia, forming a structure resembling an inverted umbrella. These function as rain-catchers, called splash cups, from which sperm are jettisoned up to several feet away during rain storms.

Illustration of Sphagnum spores and spore capsules by Phillipe Schimper (1858).
Air propulsion

Stick around in peatlands long enough, and you might bear witness to a small popping sound down near your feet. The noise is made by Sphagnum moss explosively shooting their spores in all directions, a feat first remarked upon in print by Carl Linnaeus in 1771. Sphagnum spore sacs sit on top of a hollow chamber that shrinks in size as the walls dry out, building pressure until it suddenly pops.

An 1882 oil painting of a will-o'-the-wisp by Arnold Böcklin, with the poem "Will-o'-the-Wisp" by Madison Julias Cawein.

Illustration of Riccia squamata rolling in on itself in dry conditions.
Curl up and dry

Day 25. It's not easy being green, especially when you lack an epidermis and dessicate quickly. When moisture is scarce, the liverwort Riccia squamata rolls into a tube, exposing richly hued purple scales in a bid to prevent water loss.

Illustration of moss by Robert Hooke
Micrographia

Day 26. Robert Hooke discovered cells when he used his microscope to peer closely into the structure of cork. But he also turned his magnified gaze onto this #moss, which he illustrated and published in his 1665 book Micrographia. Image from the Wellcome Collection.

Old textbook illustration of liverwort elaters.
Elation

Day 27. Peak under the hood of a liverwort sporangiophore, and you'll see fine golden tendrils hanging down from open capsules. Look closer, and you'll see these are innumerable helical threads with spiral thickenings that expand and contract in changing humidity. These are elaters, and their spasmodic writhing ensures the spores exit the capsule to find new homes.

Illustration of Ricciocarpus natans
Protective scales

Day 28. For aquatic liverworts like Ricciocarpos natans, the main source of danger doesn't come from above but instead from nibbling fish below. These plants produce purple, tentacle-like scales that extend into the murky depths and are thought to deter potential predators.

Illustration of Geothallus tuberosus, showing male and female sexual organs and the sterile tubers
Worts and tubers

Day 29. It can feel like you're being cooked out in the salt pans of southern California. The liverwort Geothallus tuberosus has evolved a unique way to beat the heat, producing starchy/oily tubers that wait out the dry season in the salt & sand, germinating with the arrival of rain.

Illustration of Conocephalus conicum from Flora Danicum
Solar-powered geyser

In 1902, the British botanist Francis Cavers noticed, "jets of fine spray" issuing from the pores of Conocephalum conicum when viewed under sunlight. The antheridia develop inside hollow chambers, and when exposed to warm light, fill with water. The ensuing pressure causes the water to erupt in a geyser that transports gametes to nearby plants.

Poem titled "Mosses" By Willis Boyd Allen