Making connections
Flowering plants (angiosperms) and pollinators have co-evolves, 200 million plus years. That’s a long time to get to know each other! However, flowering plants and insects are ‘new kids’ on the block in geological time. Ferns, cycads and evergreens, all wind pollinated, arrived on earth long before, were top of the plant web and didn’t need pollinators, just the wind.
You may be wondering if wind pollinated plants reigned supreme without the need for insects what was Mother Nature thinking? Maybe She got kind of bored and wanted to add some color to the landscape.
Mother Nature’s new idea, flowering plants, diversified at an astonishing rate with different flower types, colors, shapes and scents all to attract a new vector, not wind but insects. Plants are rooted literally to one place, they can’t pull up and move. But insects were the next best thing to move genetic information around and mix up the genes between plants, thus furthering potential variations, or diversity. This was not a one-way street. Plants had to make it worth the efforts for pollinators to move their pollen through the neighborhood. Feeding them nectar was the enticement; feed these hard workers before sending them to the neighbors. For flowering plants this is a big sacrifice – making nectar. A sacrifice wind pollinated plants didn’t need to make, they expended energy making copious amounts for pollen just in case it didn’t land where it was needed.
Flowering plants had a different idea: use insects to deliver pollen directly to the neighboring plants. Early flowers were predominately radially symmetrical meaning they looked the same to an insect no matter what direction it was approaching; think daisies, tickseed, aster. Continued evolution led to bilateral symmetry, think foxglove, turtlehead, wild indigo; only one opening was available and usually only accessed by a large pollinator to draw the hinged lip down and entering. In the case of wild indigo, a bumblebee will disappear into the flower and then backing out the bee will pick up a bit of pollen on its hind legs to carry to the next flower. Then there is the tubular flower design for those long-tongued insect and birds. All these different flower designs accommodate the ever-changing pollinator designs.
The plant and insect diversification and the constant mixing of genetic information gave flowering plants the ability to evolve quickly. Herbivores, omnivores and carnivores owe their existence to flowering plants and the pollinators. We owe our human existence to the flowering plant.
According to Ken Thompson in his book, an Ear to the Ground, a half kilo of clover honey (about 1 lbs.) represents 9 million flower visits and 7000 hours of unpaid bee labor (pollinators). Ken goes on to say honeybees aren’t the only important pollinator in America. Bumblebees, a native bee are as important. Both honeybees and bumblebees are social bees, building hive, honeybees above ground while bumble bees build in the ground. There are also many solitary bees very important to the food industry. Bee’s eyesight, somewhat similar to human’s but ranges more to the ultra-violet. They are blind to the color red. This explains why you don’t see many bees feeding at red flowers unless part of the flower exhibit ultra-violet parts. To a bee, leaves, soil and red flowers all looks brown.
We have so much to learn, observe and be humbled by in nature. For me it’s best to just take a short pause in the forest to see the intricacies of a Hepatica flower or Spring Beauty in the spring. Their flowers are a work of nature’s art and the early emerging insects need them. Really, you need to slow down or you’ll walk right past them. But, when you stop to really look, their beauty is something to behold and to be remembered so your next visit to the forest has you looking through different eyes.
Two books of great reading; short, understandable by us gardeners without a degree in botany, just good reading: Robin Wall Kimmerer, The Serviceberry; Ken Thompson, an Ear to the Ground. Ken is a British writer but don’t let that stand in the way of a great read that’s very relevant to America.
