Scientists collect snapdragon flowers in the Pyrenees to trace their ancestry

Every season, scientists from the Institute of Science and Technology Austria (ISTA) go on subject journeys to the Pyrenees. Their mission: collect snapdragon flowers to perceive their genetic make-up.

In a latest study in Molecular Ecology, they present how nature makes use of colour genes to maintain two sorts of snapdragons distinct, even after they share the identical habitat.

On the border between France and Spain lies a mountain vary that spans from the Bay of Biscay to the Mediterranean Sea. The lush valleys and excessive peaks entice many vacationers to the Pyrenees, often known as “Pireneus” in Catalan.

Arka Pal, a biologist and Ph.D. pupil from the Barton group at the Institute of Science and Technology Austria (ISTA), visits the area for a special motive. He comes to collect snapdragons or Antirrhinum—a vibrant plant that, when squeezed, resembles the jaws of a dragon.

Together with a global staff of scientists, Pal’s latest publication highlights the significance of flower colour genes that maintain two snapdragon varieties separated in a number of valleys throughout the Pyrenees, though they hybridize and occupy the identical house.

Collecting snapdragons

For the previous 17 years, scientists from the Barton group have been touring to Planoles—a Spanish village located 1,135 meters above sea degree, close to the Río Rigat and the French border—searching for snapdragons. Each subject season, round 20 researchers reside in a small hut, enterprise into the picturesque environment and collect over 5,000 samples.

“You could romanticize it and say we are hiking,” Pal jokes. “But Antirrhinum likes to grow in human-disturbed habitats, often alongside mountain roads. So, we walk these beautiful roads in the Pyrenees, sporadically climbing steep slopes through brambles and nettles to collect snapdragons.”

When in bloom, snapdragons are simple to spot with their hanging yellow or magenta petals. When they aren’t, the scientists depend on figuring out their leaves.

Pal and his colleagues maintain data of the crops’ progress and their GPS places, and collect each flowers and leaves for processing again in the hut. There they assess the colour of their samples, rating how a lot magenta or yellow they’ve, and take footage of the flowers from totally different angles. Additionally, they dry the leaves in silica gel and put them in envelopes to convey them again to ISTA to genetically analyze them.

What drives the Barton group to make investments such effort in learning these crops? What deeper insights into evolution does the colour of a snapdragon reveal?

Hybrid zones—nature’s laboratory

Pal is in how speciation occurs—how totally different varieties emerge from a typical ancestor and separate over time. In the valley of Planoles, two sorts of Antirrhinum—distinguished by their vibrant yellow (A. majus striatum) and magenta flowers (A. majus pseudomajus)—come collectively and hybridize naturally.

During the final ice age, the two Antirrhinum varieties had been geographically remoted in totally different components of the Pyrenees. As the ice melted, they seemingly steadily unfold alongside the valley from reverse instructions, forming a so-called ‘hybrid zone.”

“Hybrid zones are essentially ‘natural laboratories’ where you can study the process of speciation and evolution in nature, letting nature conduct the experiments for us instead of crossing them in greenhouses,” says Pal. The magenta and yellow snapdragons kind a slender strip, roughly 1 km in size, the place they hybridize to produce a kaleidoscope of colours.

The genetic encyclopedia

Planoles shouldn’t be the solely hybrid zone in the Pyrenees. A really comparable one additionally exists 100 km to the west, close to the city of Avellanet. The Barton group collected samples there, too. In his newest examine, Pal in contrast each hybrid zones to perceive how evolution has formed them. Back at ISTA, Pal analyzed the two units of samples to see whether or not their genomes seemed the identical.

“You can think of the genome as an ‘encyclopedia of words.’ Within this encyclopedia, there are billions of letters which make up thousands of words—our genes. Yet, only a few key ‘words’ are important to keep species or varieties separated,” says Pal.

“The same bee species pollinates both the yellow and the magenta species. Bees learn where to go to find nectar. On the magenta side, they visit magenta flowers, while on the yellow side, they frequent yellow ones,” Pal says.

Hybrids don’t entice as many bees due to their lack of distinct colour distinction required for bees to be taught, ensuing in decreased health and fewer offspring.

For snapdragons, the key trait is the flower colour, which attracts pollinators and is crucial for survival and passing genes onto the subsequent era. Despite sharing most genetic “words,” just a few crucial genes—seven to be particular—decide flower colour and stay distinctive to every species. These genes, with names as alluring as these of Pokémon, embody Rosea, Eluta, Rubia, Sulfurea, Flavia, Aurina, and Cremosa.

Color genes eclipse proximity

To sort out this information set, Pal made use of whole-genomic sequencing—a instrument generally used to map the DNA of people and different animals. In this case, he and his staff employed a novel sequencing method that had beforehand been untested for Antirrhinum.

Unlike well-studied organisms corresponding to mice or Arabidopsis thaliana crops, the place extra genomic information exists, this large-scale sequencing of snapdragon genomes concerned a course of that resembled piecing collectively an enormous puzzle.

“When we compared the Planoles and Avallenet hybrid zones, we found their genomes were quite different—they all had different mixtures of ‘words.” But the seven genes that management the flower colour had been the identical in each zones,” explains Pal. Those genes act like key phrases that keep constant.

In hybrid zones, one would anticipate close by crops to be carefully associated to one another. But when the researchers traced the crops’ genetic ancestry, they found that the flower colour genes didn’t comply with that sample. The seven genes in the yellow snapdragons from the Planoles zone had been extra carefully associated to these in the yellow crops in the Avellanet zone. The identical was true for magenta crops too.

Pal’s new examine reveals that, though there’s plenty of genetic variation between the zones, the genes chargeable for flower colour have a shared evolutionary historical past.

This discovering is essential—it suggests these colour genes assist snapdragons stay distinct and recognizable, even after they develop in the identical atmosphere, and share different genes throughout their intensive genome.