Some organisms do it horizontally, some vertically, some sexually, and some asexually. Then there are some organisms that prefer to grow a stalk that develops into an independent organ equipped with its own wings, eyes, and brain. This organ will detach from the main body and swim away, carrying the gonads that will merge with those proliferating from the separate rear limbs to give rise to new offspring.
What is this thing in the bizarre star system of Sci-Fi Film B?
Indeed, Megasyllis nipponica exists on Earth. Also known as the Japanese green worm, it reproduces through a process known as stolonization, which sounds like the genius idea of a horror sci-fi game but has evolved in some segmented worms to give future generations a better chance of survival. What has remained mysterious (until now) is how this bizarre organ, or stalk, can form its own head in the middle of the worm’s body. It turns out this is remarkable in genetic organization. But how?
The Genetic Discovery of Stalk Formation
A team of scientists led by evolutionary biologist and professor Tohru Miura from the University of Tokyo conducted the research and discovered the genetic mechanism behind stalk formation. It starts with Hox genes. These are a set of genes that help determine the different parts of the embryo that will become the head, thorax, abdomen, and so on. In segmented worms like M. nipponica, different Hox genes organize the segments that make up the entire worm’s body.
The Development of the Stalk and Head Formation
The front part, or stalk, of M. nipponica is neither male nor female. The worm has organs called sexual embryos at the lower part of the rear end. When the embryos begin to transform into eggs or auster, the genes responsible for head formation (different from Hox genes) become active in the middle of the stalk’s body.
Here the stalk begins to develop its head. Its head grows a cluster of nerve cells that act as a brain, along with a central nervous system that extends into its body. The eyes of the stalk and its wings and swimming hairs also emerge. It leaves behind
Before the stalk can set off on its own, it must develop enough to be fully capable of swimming independently and finding its way to another stalk of the opposite sex. The fully developed stalk looks like an alien organism attached to the rest of the worm’s body. In addition to its own nervous system and something akin to a brain, it also possesses a pair of bulging eyes and a pair of wings and its own digestive tract. These eyes grow large for some reason, as the embryo often needs to navigate through murky waters.
The stalk’s wings can sense the environment around it, but researchers point out that it has a more important function – detecting pheromones released by the opposite sex. Still, the stalk is not an exact replica of the stalk. It lacks some of the more developed features of the worm, such as a digestive tract with several specialized regions, perhaps because its sole purpose is reproduction. It dies shortly afterward.
Stalk Evolution
What could make the stalk evolve in the first place? More research needs to be done, but for now, it is believed that this bizarre ability may arise in some segmented worms when the genes that develop the head move further from the body, but it remains unknown why this gene movement developed in the first instance.
The worm also regenerates the stalk at a high rate, which may give it the best chance to reproduce its kind. Get ready for an adventure.
Source:
Scientific Reports, 2023. DOI: 10.1038/s41598-023-46358-8
Reader comments: 50
Elizabeth Rayne is a being who writes. Her work has appeared on SYFY WIRE, Space.com, Live Science, Grunge, Den of Geek, and Forbidden Futures. She lurks outside of New York with her parrot, Lestat. When she’s not writing, she’s either shapeshifting, drawing, or disguising herself as an obscure character. Follow her on Threads and Instagram @quothravenrayne.
.lwrp .lwrp-list-item .lwrp-list-link .lwrp-list-link-title-text,
.lwrp .lwrp-list-item .lwrp-list-no-posts-message{
}@media screen and (max-width: 480px) {
.lwrp.link-whisper-related-posts{
}
.lwrp .lwrp-title{
}.lwrp .lwrp-description{
}
.lwrp .lwrp-list-multi-container{
flex-direction: column;
}
.lwrp .lwrp-list-multi-container ul.lwrp-list{
margin-top: 0px;
margin-bottom: 0px;
padding-top: 0px;
padding-bottom: 0px;
}
.lwrp .lwrp-list-double,
.lwrp .lwrp-list-triple{
width: 100%;
}
.lwrp .lwrp-list-row-container{
justify-content: initial;
flex-direction: column;
}
.lwrp .lwrp-list-row-container .lwrp-list-item{
width: 100%;
}
.lwrp .lwrp-list-item:not(.lwrp-no-posts-message-item){
}
.lwrp .lwrp-list-item .lwrp-list-link .lwrp-list-link-title-text,
.lwrp .lwrp-list-item .lwrp-list-no-posts-message{
};
}
Leave a Reply