Scientists Perplexed by Unexpected Evolutionary Change in Flowers

When Charles Darwin first codified evolution using natural selection, he saw it as a step-by-step process. He didn't see these slow changes until the hands of time mark a long time as he wrote in his original work, 'The Origin of the Species'.

Evidence of evolution in Colorado blue columbine

(Photo : Markus Winkler/Pexels)

Since the advocacy of evolution, biologists have argued whether it always occurs in small, step-by-step steps over a long period of time, or whether sudden changes cause imbalance. Large morphological changes often occur within a short geological timescale, during which the intermediate morphology may not be fossilized, according to ScienceDaily.

The question remains whether many small changes have occurred in a short period of time, or whether it is due to a single large mutation. Therefore, researchers need to actually see evolution if they want to show evidence that sudden changes can accelerate evolution.

According to Sci-News, diversification of flowering plants (angiosperms) is one of the most important episodes in the history of life, transforming global ecosystems, insects, amphibians, mammals, early birds and other clades. Brought about diversification.

History Life on land has become more diverse than life on the sea. Charles Darwin's rapid divergence from 135 to 65 million years ago, when angiosperms dominated many land environments and replaced gymnosperms established by the end of the Cretaceous period.

Enter the Colorado blue columbine. In one population, mutations caused many plants to lose their petals with a symbolic nectar spur. It's not uncommon in columbines, but it seems that a spur-free condition has been established in the area. About a quarter of the plants are featureless.

The team examined the plant's genome to find the cause of the abnormal morphology. They investigated the gene APETALA33, which is known to affect spurious development. They found that this single gene regulates the overall development of flower stems and nectaries.

Genes are either on or off, so it's as easy as making changes, as said by lead author Zachary Cabin. But that simple difference causes a fundamental change in morphology. He added.

With a single defective gene, the mutated plant develops petals and nectar-free flowers.

Read more: How Flowers Adapt to Their Pollinators

The surprise selection of change in action

Among all kinds of columbines, you will find rare specimens that bloom without the spur of nectar. However, Cabin and Hodges knew this was more than a coincidence, as a quarter of Colorado's population lacked this property. He finds it strange because the spurs produce nectar that attracts the pollen maters of the plant.

Hodges is familiar with columbines, and all his previous studies suggest that nectar spurs are important to the group. Even the slightest changes in structure drive speciation and diversification of the genus.

As per The Current, researchers also want to track how the spur is spreading to the population. Different forms of mating, but genetic evidence suggests less mating between the two groups. Colorado blue columbine can divide into different species, especially because the two species appear to be dependent on different pollen maters.

Also read: Ancient Flowers Found Preserved in Amber at Dinosaurs' Feet 99 Million Years Ago