How a Tree and Its Moth Shaped the Mojave Desert | Science | Smithsonian
Photo and illustration credits: All photographs except the picture of C.V. Riley are by plant and their yucca moths are the classic textbook example of "mutualism. The termite-protozoa relationship and the yucca-moth relationship are the. Header Image - The Joshua Tree Genome Project A female yucca moth in the process of laying eggs in a Joshua tree flower. Although on the surface the relationship between the Joshua tree and yucca moths seems to. Photo © The Nature Conservancy (Chris Helzer) The moth's larvae depend on the seeds of the yucca plant for food, and the yucca plant can only So each species depends upon each other for survival, and both benefit from the relationship. I've always found symbiotic relationships super interesting.
The female yucca moth is the sole pollinator of the yucca, and the yucca is the only caterpillar host plant of the yucca moth. In fact, the yucca and yucca moth share a symbiotic relationship that is so specialized, each yucca species is pollinated by only one type of yucca moth. Classification and Range Yucca moths are members of the family Prodoxidae and the genus Tegeticula.
Of the 80 or so species found worldwide, about 30 are native to North America. These moths are typically found wherever yucca plants grow, generally throughout the hot, desert regions of the southwestern United States and Central and South America. Members of the Asparagaceae family, the yucca genus contains at least 30 species of trees and shrubs.
Yuccas are characterized by their tough, sword-like leaves and large clusters of fragrant, white flowers. These plants generally grow in U.
- Symbiosis of Yucca Moths & Yucca Plant Trees
- How a Tree and Its Moth Shaped the Mojave Desert
Department of Agriculture plant hardiness zones 3 through 10, although hardiness varies by species. Yucca Moth Description Yucca moths are typically silvery-white and small — usually less than an inch long.
Some have dark markings and hair-like fringes on their wings. Without nectar to attract pollinators, Joshua trees rely solely on this unassuming moth for pollination.
Yucca moths use their dexterous jaw appendages to collect pollen from Joshua tree flowers and deposit it on the female parts of each flower as the moth moves between blooms. When they hatch, the yucca moth caterpillars eat the seeds—their only food source—before crawling to the ground to form cocoons. And the cycle begins again. According to Christopher Smitha biologist at Willamette University who studies pollinator relationships, the relationship between yucca moths and Joshua trees is unlike anything else in the natural world.
His previous research focused on cactus longhorn beetles and the spiny plant species they interact with throughout the Sonoran Desert. But nothing, he says, compares to the Joshua tree and the yucca moth.
Most pollinators accidentally assist the plants they pollinate. Moreover, this partnership has been going on for millions of years. Joshua trees do more than provide artistic inspiration: These hideously beautiful shrubs provide food and shelter for animals in the Mojave scrublands, where resources are notoriously scarce.
Symbiosis of Yucca Moths & Yucca Plant Trees | Home Guides | SF Gate
During the spring, its flowers are one of the only sources of wet food available for insects, ravens, and ground squirrels. The unremarkable-looking yucca moth is one half of an evolutionary partnership that dates back millions of years.
The two are so different, scientists have even advocated splitting Yucca brevifolias into two species. But what evolutionary reason is responsible for this divergence?
Ecologists long believed that one species of yucca moth Tegeticula synthetica pollinates both kinds of Joshua trees. But ina team of scientists discovered that a genetically distinct yucca moth T.
Like the Joshua trees themselves, this moth was shorter than its western counterpart. Even more eerie, the difference in the distance between the stigma and ovule between the two tree types was the same as the difference in body size, head to abdomen, between the two moths.
What is the deal with Joshua trees and yucca moths?
To determine if co-evolution brought about this suspicious speciation, Smith led a team of citizen scientists in and to collect morphological data in the one spot where the two species of Joshua trees and their corresponding moths live in harmony: Smith and his team observed that yucca moths deposit their eggs more efficiently in their corresponding Joshua trees, and the Joshua trees in turn provide more space for the eggs when pollinated by the prefered moth.
Though moths will pollinate flowers whose styles are too long, they almost never successfully lay eggs that hatch into caterpillars. When the styles are too short, the moths can damage the flowers with their ovipositor.
The Joshua trees could be evolving in reaction to something in their natural environments, and the moths could be responding, which demonstrates evolution, as one species changes in response to environmental stresses and then the other evolves in response to the first species resonding —but not co-evolution, where both species change reciprocally in response to one another.