Roses, the symbol of love and romance, are also famous for their sharp thorns. However, the secret behind this unique “weapon” of the flower has only recently been uncovered.
The defense mechanism through sharp thorns is not only found in roses but also in other flowers, such as the thorny vine, and some plants like tomatoes, eggplants, rice, and barley, as reported by CNN on August 2nd.
But how do these plants, which have evolved in various ways over millions of years, share the characteristic of having thorns?
Thorns in roses originated at least 400 million years ago. (Photo: REUTERS).
A team of international researchers discovered that the answer lies in their DNA, which originates from an ancient gene family responsible for all thorn variations in plants, according to a report published in the journal Science.
The evolution of thorns
Sharp thorns have existed for at least 400 million years, dating back to a time when ferns and their relatives exhibited some thorns on their stems. Since then, this characteristic has appeared and disappeared through various stages of the evolutionary process, according to co-author Zachary Lippman, a plant biologist and professor of genetics at Cold Spring Harbor Laboratory in Long Island, New York, USA.
One of the most diverse plant genera, scientifically known as Solanum, which includes plants like potatoes, tomatoes, and eggplants, first developed thorns approximately 6 million years ago.
Utah State University (USA) has documented that this genus currently has over 1,000 species worldwide, with about 400 species possessing thorns.
Thorn evolution in plants serves as a defense mechanism against herbivorous animals and can aid in growth, competition among other plants, as well as function in water retention.
The team of experts discovered an ancient gene family called Lonely Guy (LOG) that plays a role in maintaining the thorn characteristic in plants, allowing thorns to appear or disappear in specific species over millions of years.
This new finding not only allows scientists to study the creation of thornless varieties but also provides new insights into the evolutionary history of an incredibly diverse plant genus on Earth.
