Tomorrow I have a non-biology majors lab in which we are scheduled to cover gymnosperms and angiosperms (think “pines & flowering plants”.. its not 100% accurate, but it will do). I was up last night until 3am preparing for today’s classes, so you would think I would hit the sack but no, I am in awe of Commelina communis, a little flowering plant that is popping up all over our forest floor at school.
First off, its common name is the Asian Dayflower and its quite cute. It was assigned to its genus & species by none other than Carolus Linneaus himself (he of the Kingdom Phylum Class…..). Its native to Asia, but has been in the US since at least the 189o’s (sidebar: how long does a plant have to succeed in this country before we will start calling it a native?? This thing is probably more native than I am).
The flowers on this are striking, with 3 sets of male structures: long lateral stamens, medium length (medial) stamens, and finally, the short staminoides.
Here is the cool part. The staminoides produce only a little bit of infertile pollen, whereas the medium and longer length stamens produce normal pollen, but the medial stamens and staminoides are brightly colored. The only purpose of the showy staminoides is subterfuge: flies and bees use the longer stamens as a landing pad to get a meal of pollen (most of which is basically the equivalent of plastic fruit). Meanwhile the longer stamens are decorating their abdomen with fertile pollen. The female structures (stigma (stigmata? shiver)) on these flowers are long too, so that abdomen-riding pollen will be deposited on the lady parts on the next visit.
Pollen is expensive energetically to make (gotta go through meiosis and then a seperate mitotic division and put down a lot of protein and other biochemicals into the pollen coat),
so this is kind of a gamble by the plant. Even the infertile pollen of the stamioides is costing the plant energy. If the pollinator lands in the wrong orientation, the lateral stamens miss the abdomen but the insect gets the reward anyhow (this is called Pollen Theft), so you might predict that the staminoides and medial stamens play a role in making sure that insect lands “correctly”. This cool paper shows exactly that: removing the medial stamens results in a lower “legitimate landing to total landing” ratio. Brillant stuff. Offer the sucker some french fries on a high shelf and he always ends up with ketchup on his shirt.
If you think about it, this also attests to the evolutionary tango that flowers and their pollinators are in: if the fly or bee population that pollinates these Dayflowers chagnes their average body dimensions the whole thing could be off – no pollen on the tum tum (but they still might get the yum yum), so no seeds and no kids.