By Jonny Lupsha, Wondrium Staff Writer
A sign of hope for an endangered tree species blossomed in Missouri. The Karomia gigas tree is dangerously close to extinction, but a purple flower recently bloomed on one for the first time in recorded history. Flowering plants evolved rapidly in terms of Earth’s lifespan.
A truly unique purple flower bloomed on a Karomia gigas tree, according to National Geographic. The website said that Karomia gigas is so rare that only two dozen exist in its native Tanzania, which is part of why the recent flowering—at the Missouri Botanical Garden in St. Louis—is so special. The other part is that until now, the tree’s flower had never been seen in recorded human history.
Flowering plants went from first bloom to the dominant plant form on Earth in about 40 million years, which is a short period of time when discussing life on Earth. In her video series Plant Science: An Introduction to Botany, Dr. Catherine Kleier, Associate Dean of Faculty in the College of Agriculture, Food, and Environmental Sciences at California Polytechnic State University, said there are as many as 400,000 species of flowering plants.
Diversity in Dispersal
Conifers, ferns, and mosses were around long before flowering plants and they took a long time to evolve and diversify, so what’s the deal with flowers?
“The answer may lie in the fact that many flowering plants are both pollinated and dispersed by animals,” Dr. Kleier said. “An animal moving pollen between plants could become more specialized and get pollen from only one type of plant. Now, the plants pollinated by that animal are reproductively isolated from other plants.
According to Dr. Kleier, this is the key to speciation, or the formation of new species. Another way that animals can be key to speciation is through dispersal.
“If an animal disperses a seed to a new environment, it can be in a new island, figuratively speaking,” she said. “That is, the animal has dispersed the seed to a new location where it can no longer breed with its old population, so it becomes reproductively isolated, and speciation occurs.”
An Inflorescence by Any Other Name…
An interesting point related to the diversity of flowers is how they’re described. Other than the actual names of the 400,000 species of flowering plants, Dr. Kleier said that botanists don’t seem to have nearly as many words to describe their flowers.
“When I think of flower shapes, I generally think of symmetry—flowers can be radially symmetrical or bilaterally symmetrical,” she said. “There are a few descriptors like tube-shaped or bell-shaped flowers, but other terms would be reserved for specific flowers, and botanists don’t use them broadly.
“Most wildflower ID books will use color; others will use inflorescence types.”
Dr. Kleier said that inflorescence describes how flowers are arranged on the stem. For example, a single flower on a stem is called a solitary inflorescence, while flowers that alternate up the stem are an inflorescence that’s called a raceme. If a raceme is tightly compressed on the stem, it’s called a spike.
“An inflorescence that has numerous flowers forming a sort of umbrella shape is called an umbel, from the Latin umbella, meaning ‘sunshade,’ which also gives us the word umbrella,” Dr. Kleier said.
For now, the world will have to wait to see how botanists describe the purple flower of the Karomia gigas.