The Mediterranean marine worm has large eyes

Precise News

Scientists are amazed at the discovery of a bristle worm with such sharp-seeing eyes that they can measure up to those of mammals and octopuses.
The Vanadis bristle worm has eyes as big as millstones—relatively speaking.
Indeed, if our eyes were proportionally as big as the ones of this Mediterranean marine worm, we would need a big, sturdy wheelbarrow and brawny arms to lug around the extra 100kg.
Vanadis bristle worms, also known as polychaetes, can be found around the Italian island of Ponza, just west of Naples.
He was hooked as soon as his colleague Michael Bok at Lund University showed him a recording of the bristle worm.
And it was this combination of factors about the Vanadis bristle worm that really caught Garm’s attention.
But if, instead, the worm uses UV light, it will remain invisible to animals other than those of its own species.
Vanadis’ eyes are built simply but equipped with advanced functionality.


The discovery of a bristle worm with eyes as keen as those of mammals and octopuses has scientists in a state of shock. It is possible that these marine worms speak a secretive language that only they can understand by using UV light, according to researchers from the Universities of Copenhagen and Lund. A long-running argument concerning the evolution of eyes is resolved by the superior vision of such a primitive creature.

With relative exaggeration, the eyes of the Vanadis bristle worm are as large as millstones. Truly, if our eyes were as large as those of this marine worm from the Mediterranean, we would require a large, robust wheelbarrow and strong arms to lift the additional 100 kg.

The set of worm’s eyes is about twenty times heavier than the rest of the animal’s head and looks grotesquely out of place on this transparent, tiny marine creature. Like if its body were strapped with two enormous, dazzling red balloons.

Polychaetes, commonly referred to as vanadis bristle worms, are found in the vicinity of Ponza, an Italian island located to the west of Naples. In line with certain summertime revelers on the island, the worms are nocturnal and hidden from view during the height of the sun’s rise. That being said, what is the purpose of the walloping peepers on this polychaete after dark?

Anders Garm, a marine and neurobiologist at the University of Copenhagen, was unable to ignore the query. The researcher felt driven to begin investigating without regard to other plans. His fascination began the moment he saw a recording of the bristle worm, thanks to a colleague Michael Bok at Lund University.

Together, we set out to solve the riddle of why a transparent, nearly invisible worm that feeds at night evolved to have enormous eyes. Therefore, the primary goal was to determine if the worm’s large eyes gave it good vision,” according to Michael Bok, who co-authored a recent research paper with Garm that addresses this very question.

It turns out that the Vanadis has highly developed vision. Studies have revealed this worm’s ability to see and follow the movements of small objects with its eyes.

“This is incredibly fascinating because, normally, only vertebrates and arthropods—insects, spiders, and the like—have the capacity for such an ability. ] and cephalopods (squid, octopus). It has never been shown outside of these groups that such a sophisticated and thorough perspective is possible. The worm actually has exceptional vision, as our research has demonstrated. Although it’s a very basic organism with a tiny brain, its vision is comparable to that of mice or rats “says Garm.

Because of this, the worm’s eyes and remarkable vision are unlike any other in the animal kingdom. And what really drew Garm’s attention to the Vanadis bristle worm was this particular combination of factors. This was undoubtedly an example of the kind of extremely complex functions that otherwise simple nervous systems can have, according to the researcher’s work.

UV light and coded communication.

The current focus of the research is to determine what led to the worm’s remarkable visual development. Aside from their eyes, which require light to register in order to function, the worms are transparent. They therefore cannot be naturally transparent. This implies that there are trade-offs involved in their evolution. The Vanadis must have paid a price for becoming visible, but the advantages of having eyes for evolution must outweigh the drawbacks.

It’s unclear exactly what the worms gain, especially since they are nocturnal creatures that hibernate during the day, when eyes are typically at their most efficient.

The worm’s hiding place is unknown to us because no one has ever seen it during the day. We therefore cannot completely rule out the possibility that it uses its eyes during the day. What is known is that it uses the night for its most vital functions, such as mating and food gathering. Thus, this is probably the time when its eyes matter “says Garm.

These worms’ differing light wavelength perception from human vision could contribute to the explanation in part. Their eyes are not capable of seeing ultraviolet light, which is what they see. Its eyes could be meant to detect bioluminescent signals in the otherwise completely dark sea at night, according to Garm.

According to our theory, the worms themselves are bioluminescent and use light to communicate with one another. You run the danger of drawing in predators if you use regular blue or green light for bioluminescence. However, if the worm uses UV light instead, it won’t be visible to animals other than those in its own species. Hence, our theory is that they have evolved keen UV vision in order to have a code of communication related to mating,” says Garm.

Alternatively, it could be that they are searching for UV bioluminescent prey. Nevertheless, it’s extremely exciting because no other animal has been shown to exhibit UV bioluminescence. Therefore, the researcher says, “We hope to be able to present this as the first example.”.

fascinating for studies of evolutionary history and robotics.

Following this discovery, Garm and his research colleagues have begun collaborating with robotics experts from the University of Southern Denmark (SDU)’s Maersk Mc-Kinney Møller Institute, who draw technological inspiration from biology. Collaboratively, their aim is to explore the feasibility of comprehending the underlying mechanism of these eyes to the extent necessary for its technological application.

We are trying to figure out how animals with as simple a brain as these can process all of the data that their enormous eyes are probably able to gather, in collaboration with the robotics researchers. This implies that their nervous system contains incredibly sophisticated information processing methods. And these mechanisms might be built into computer chips and used to control robots if we can mathematically identify them,” says Garm.

Garm claims that another reason Vanadis’ eyes are intriguing from the perspective of evolutionary theory is that they might resolve one of the most contentious scholarly arguments surrounding the theory: whether eyes have arisen multiple times, independently of one another, throughout evolutionary history, or if they have evolved only once and into every form that we know today.

Vanadis’ eyes have a straightforward design but cutting-edge features. Meanwhile, their evolutionary history has only lasted a few million years, which is a comparatively short time. As a result, they had to have evolved separately from things like human eyes, and it is feasible for vision to develop quickly even with a high degree of function.

scroll to top