Flowers → four products to attract pollinators: nectar (sweet liquid), pollen (high protein— all amino acids, other lipids and nutrients required for bees), floral oils, edible body of some fruits
Aroma, appearance, texture shaped by natural selection to attract pollinators
Plants pollinated mainly by birds → not as much scent bc birds don’t smell! (Hibiscus, etc.)
Buttercups = really shiny, bees attracted to the sheen
Bees can distinguish flowers solely by micro-texture
Plants also signal to bees via electrostatic charges (+ bee, - flower)— marks left by bees can signal to other bees that a certain flowers have been visited, or flowers may “guide” bee to pollen/nectar
Bees don’t see red, but do see UV
Angiosperms = flowering plants, evolved from gymnosperms (no flowers or encased seeds— pine trees, gingkos)
Early angiosperms = water lilies, magnolias — actually heated up their flowers to attract pollinators (Elephant ear still does this!)
115-130 million year evolution — vast diversity/versatility of forms, double fertilization method, co-evolution with pollinators → behind their success
Early pollinators (beetles, bees, flies) → around long before flowers
Bees → collect pollen in pellets that stick to their legs for food; collect resin & bring back to hive as anti-fungal, repair material, etc.
Case studies of flowers/their pollinators
Bucket orchids— fill basins with liquid; bees fall in and struggle in the liquid, where it gets pollen precisely placed on it, then can work its way free in hours!
Actually a much larger array of moths than butterflies (10k vs 700 in the US); proportional affect on pollination
Yucca moths → one of few cases of “deliberate” pollination of yucca blossoms— forms pollen balls, deposits
Bees get pollen all over them, then collect & use most of it— whatever is left, that they can’t reach or where they “forget to look,” goes on to pollinate
Many flowers “hide” their pollen from bad pollinators— tomato plants do this; = “salt-shaker” flowers. Can be pollinated by buzz pollination: bees buzz at specific frequency (300-400 Hz), which releases pollen grains
To reduce reliance on on single honeybee species, more interest in other species (not honey-makers) that
Along with insects, pollinators = birds (hummingbirds and the like), bats, rodents, lizards, humans (date palms pollinated by hand!)
Humans actually have a history of pollinating many species— esp grains, and today many apples (clones must be matched specifically)
Part 2: Growing, Breeding, & Selling
History of growing plants for the flowers themselves (aesthetics) rather than for food
Oldest gardens = Egyptian, Chinese
Western gardens most influenced by Greek, Roman (many myths about flowers, agriculture)
Floating gardens made by Aztecs, still existing— layers of rafts with soil
Persian/Islamic gardens: fruit trees & roses, jasmines, tulips, etc. → stimulated gardening across W Asia
Chinese gardens influenced Japanese → started only in 6th; by 11th c influenced by Chinese landscape paintings (just as European gardens began to be influenced by European landscapes)
Gardening in more modern times
17th c Holland → most expensive tulips ever! Not as bad anymore…
Today, some orchids are most expensive blooms: $262k for one; some native ones illegally transported, $5-10k per plant
Cut flowers— “vase life” is important quality
Ethylene release → hastens death; flowers stored in v climate controlled environments to minimize this → roses can be cut in December to be sold in Feb!
Some plants being genetically engineered for ethylene resistance → keep flowers much longer
“Gene blasting” → DNA on gold particles shot into egg cells
More common/cheaper = mutagenesis
New technique to save hybrid plant embryos that wouldn’t survive— culture in flask
Attempts to make new colored flowers (black pansies, blue roses) by hybrid breeding, genetic engineering (the latter by genetic eng and RNAi!!!)
Modified flowers often lack scent, bc fragrance molecules usually depend on many biochemical pathways → easily disrupted
Today, most cut flowers sold in the US grown in Colombia (because of one guy’s term paper talking about good conditions, lead to startup, and took off from there)
Industry promoted by US govt to create decent jobs not in drug cartels
Still, harsh & tedious work w exposure to chemicals, pesticides, etc.
Flowers flown on cargo planes to the US… most to Miami, then distributed by truck
Each shipment inspected for insects/fungi and entire thing can be rejected for one flaw, but not tested at all for pesticides
Bedded flowers (actual plants) mostly grown in US nurseries; sold early and in “advance bloom” to appease people’s wishes and need for flowers, much before naturally would be blooming
Biggest flower auctions = Dutch; in a building with biggest footprint in the world (!?)
Saffron → worth its weight in gold; only source is the strands per flower of the crocus, which only lasts one day; only several flowers bloom per plant → very low yield
Honey → gets flavor from nectar being close to petals; most are heated/pasteurized but single flower & raw honeys are most flavorful!
Mayan honey (from MX)
Pollen = very nutritious, contains all amino acids
Fragrances: flowers = “chemists” of nature, huge diversity of scent molecules to attract pollinators
Can do “smellings” with flowers in a jar like coffee or wine tastings!
Ancient Egypt → central of fragrances and perfumes in ancient world, used v fancy containers— popular scents = blue water lily
Most popular flowers used in perfumes grown far from native origins (ylangylang, rose)
Takes thousands of pounds of rose flowers to make 2 lb rose absolutes (sp?), costs ~$2k, flowers only harvested in the morning when most fragrant
Perfumes → three notes, like a chord; top (head) note, middle (heart) note, base note
Reveal themselves from lightest to heaviest MW; head notes 5-10 min after application to base notes 1 hour + (to a day!), base notes mixing with middle notes to form bulk of perfume
Ex. Top notes = citruses; middle notes = rose, lavender; base notes = vanilla, musk
Creation of synthetic fragrances → leveled playing field for perfume companies, and helps protect endangered species like musk deer (?)
Part 4: Flowers in Literature, Art, & Myth
Floral references in the Bible actually pretty rare
Origin of Western poetry about flowers = Greek: anthology = group of flowers
Did Shakespeare ever see the flower species he writes about?
Species that are written about in English poetry change over time, except for roses— ephemeral
Asian tradition: extensive tradition of poetry/literature about flowers, but focus on themes of symbolic beauty, landscapes, love rather than ephemeral love/lust as in the West
Ancient China → lyrical poems, about rural life, lots of symbols
Japan → short poems, often syllable counts like haiku (usually focused on wit/rhetoric), waka
Many songs written about/including flowers…
Depictions of flowers in art
No record of cave paintings with flowers
Oldest examples are from Ancient Egypt
Long tradition of floral images in Chinese and Japanese art; appeared in European art a little later (initially associated with death and pagan cultures)
Dutch hyperrealist still-lifes
Post Raphaelites → so many paintings of young girls with flowers!
Then 1890s: Manet, Monet → moving away from realistic still life style; Monet painted flowers less for the flowers themselves than for the color & artistic exploration
Many photographers— Ansel Adams, Maplethorpe, Robert Rice, J. Scott Peck, etc. (just a random selection of those mentioned!)
More recently artists “photographing” using flatbed scanners
Many coins and paper bills in currencies around the world include flowers
Flowers on stamps
Flower arranging
Tons of bouquet offerings by ancient Egyptians to pharaohs
Japanese art form ikebana (sp?)— four major styles
Illuminated manuscripts in Europe → floral illustrations in marginalia, on letters (helped illiterate readers follow story by symbolism)
Flowers in rugs (Persian, Indian, Chinese)
Flowers in ceramics: earliest examples = tulip motif found on Minoan ceramics, then Chinese, Ottoman
Newer forms of flower art:
Scanning and 3D printing flowers, including molds for lost wax casting of bronze sculptures
Glass art
Most famous = Ware collection in Boston? Blashkas?
Also Venetian style, millefiore (derived from “thousand flowers”, made with lots of very thin layers)
Part 5: Flowers in the Service of Science & Medicine
Orchids → important subject of study for Darwin — all weird shapes derived from standard flower parts!
Cross- vs self-pollination: cross-pollination → more seeds, fitter next generation (crazy idea at the time when livestock often inbred)
Plants with flowers that did not favor self-pollination (ex. one flower doesn’t have both sex organs) = favored by natural selection
Wind pollinated plants
Jojoba— native to Sonoran desert, produce oil identical to sperm whale oil so great for shampoo! Flower design has aerodynamics to trap airflow in spirals around female flowers for up to minutes, increasing chance of pollen capture!
Bee vision
We see at much higher resolution than bees, but they are usually closer to object
Studied foraging behavior using RFID-tagged bees
Uncertain still how exactly olfaction works— lock & key mechanism of scent molecules and receptors? Perhaps vibrational resonance is involved in stimulating olfactory neurons? Can study with insects
Honey → medicinal/healing properties: high sugar content and low pH make it antimicrobial; bees add enzymes such as those breaking sugar into hydrogen peroxide (antiseptic)
Manuka honey (from tea tree, eucalyptus) → especially healing proprieties, used to treat sterile wounds and burns
Greenery and nature scenery → improves patient conditions in hospitals; even flowers in rooms!
Concept practiced since ancient times, but not so much in modern hospitals
Viewing flowers makes us smile
True floral fragrances have general positive effect; research into whether actual molecules may act as anxiolytics (thought to do so in insects to slow them down when pollinating)
Extinction threatens many flowering plants, often bc decline in pollinators
Even if many undiscovered species
What can we do? But local and organic flowers, pay fair prices…