Buzz
While most people perceive snails and slugs as nuisances, these slippery creatures are far more than mere garden invaders. They astound scientists with their remarkable skills, and some have even become media sensations.
These slow-moving creatures can sometimes seem a bit unsettling. They have been known to dwell inside humans and, with the help of the military, have been transformed into cyborg spy snails.
10. A Mysterious Tale of Survival
Hahajima Island in Japan is home to a delicate snail. The term “delicate” refers to its tiny size—just about 0.25 centimeters (0.1 inches). A thumb could easily crush Tornatellides boeningi.
Recently, researchers collected bird droppings from the island and discovered snail shells inside. Strangely, some of these snails seemed to be alive. Intrigued, the team decided to feed over 100 of the mollusks to two bird species known to snack on snails.
Surprisingly, around 15 percent of the snails were expelled unharmed. One even gave birth shortly after being excreted. The digestive journey isn’t exactly a theme park ride—snails endure a tough passage lasting anywhere from 30 minutes to two hours. The reason so many appear to survive the ordeal remains a mystery.
What are the leading theories behind this phenomenon?
Smaller size equals better survival. Snails with more diminutive shells are less likely to crack or allow digestive juices to seep in. Tornatellides may also shield themselves by covering the shell's opening with a protective mucous layer.
9. Why Mating Among Snails Is So Slow
It might be easy to think, 'It’s slow because they are snails.' While garden snails are hermaphrodites and technically able to reproduce alone, they tend to prefer a mate. Each snail carries both eggs and sperm, aiming to both fertilize and be fertilized at the same time.
The real reason snails engage in slow, lengthy mating that can last up to three hours—often resembling more of a cautious interaction than a passionate union—may be tied to their health. Researchers suggest that while snails don't mind releasing sperm, they are highly selective about the quality of sperm they accept. This leads them to carefully assess the situation.
If a mate is not ideal, the other might attempt to impregnate it while avoiding the unhealthy snail’s own attempts at reproduction. The entire mating ritual is filled with focus and frustration. The complexities of snail courtship take precedence over all else, even safety. This is why mating snails are often exposed and oblivious to their vulnerability.
8. Snails Found Inside Humans
In 2018, an 11-year-old boy was playing in a tide pool in California when he scraped his elbow. His parents ensured the wound was disinfected and cleaned. However, a week after their beach trip, the wound was still infected. They took their son to the doctor, who found a persistent blister that continued to grow. The child appeared otherwise healthy.
The medical team decided to drain the red, pus-filled blister. Once it was opened, they were surprised to find a tiny sea snail inside. The checkered periwinkle was still alive, despite having been covered in human tissue and wound fluids for over a week.
Fortunately, the periwinkle never nibbled on the boy. As herbivores, periwinkles typically survive by browsing on shoreline rocks. Since air isn't always ideal for sea snails, this species can seal its shell with a thick layer of mucus. This protective layer helped prevent the periwinkle from suffocating inside the wound.
7. Stepfather Snails
In a 2012 study, researchers discovered another remarkable father figure in the animal kingdom. The male marine whelk takes on the role of primary caregiver, while the female departs after mating and attaches egg sacs to his back. Each sac contains around 250 eggs. The male must carry these sacks for about a month, losing significant weight in the process.
Despite the challenges, the whelk is a devoted father. This species crawls through California’s mudflats, ensuring the eggs stay cool and hydrated. As if being a single father isn't difficult enough, his offspring are violent. Once hatched, the baby snails fight amongst themselves. Only the few surviving siblings are well-fed.
Even worse, DNA analysis revealed that, on average, a male only cares for 24 percent of his own offspring. The rest are fathered by up to 25 other males involved with the mother. Researchers believe the males take on this responsibility to demonstrate their parenting abilities, thus securing more mating opportunities with females.
6. Mutant Love Drama
The common garden snail is something many are familiar with. Typically, their shells spiral only to the right. For the direction to reverse, a rare genetic mutation must occur. In 2016, one such snail was discovered in London and named Jeremy.
A year later, researchers sought to investigate 'lefty' genetics further and decided they wanted to breed with him. However, due to his unique condition, Jeremy could not successfully mate with regular snails, so they had to find another mutant to pair him with.
In 2017, the search began to find Jeremy a mate (they are hermaphrodites). The world’s largest broadcasting network decided to step in. The BBC brought attention to the lonely snail's plight, and two partners were found. Lefty, donated by a snail lover from Ipswich, and Tomeu, who was saved after a restaurant owner in Catalan, who was watching BBC, noticed that one of the appetizers was a match.
With the entire world watching, Jeremy was rejected. The other two snails paired up and produced 170 baby snails. However, shortly before Jeremy passed away that same year, he did manage to have a brief fling with Tomeu, resulting in 56 offspring.
5. They Get Kidnapped
Antarctic pteropods are minuscule, glass-like snails. Given their fragility and their existence in the vast, perilous ocean, pteropods have evolved to be extremely toxic. However, this survival mechanism comes with the unusual risk of getting kidnapped.
At one point, crustaceans known as amphipods discovered that the snails are so toxic that predators avoid them. Not only are the amphipods immune to the mollusks' lethal shock, but they also kidnap the pteropods and use them as protective shields.
The crustaceans employ two pairs of legs to hold the snails captive, carrying the unfortunate creatures like living backpacks. It takes several snails to form the living armor, but they can cover up to half of the host's back. This criminal tactic works in the amphipods' favor, as it persuades predators to search for other meals.
The snails are at a severe disadvantage. Once abducted, they are unable to feed and eventually starve. To make matters worse, their lifeless bodies are often kept by the amphipods that took them.
4. Lonely George
There was a Hawaiian tree snail with an extraordinary existence. This slimy creature never ventured up a tree in the wild, as Lonely George was born and raised in a lab setting.
His ancestors—the last 10 Achatinella apexfulva—were captured in 1997 for a breeding initiative. However, the snail romance proved disastrous. For unknown reasons, all the offspring perished, leaving only George alive. He spent 14 years at the University of Hawaii, becoming a local celebrity and even conducted tours to teach children about the environment.
George was the sole survivor of his species. The same enigmatic conditions that wiped out his siblings also claimed the original 10 adult snails. Once abundant, Hawaiian tree snails were so numerous that 19th-century records mention Europeans collecting up to 10,000 of them daily.
This excessive harvesting contributed to the species' decline. To make matters worse, the introduction of the rosy wolfsnail to Hawaii to control the African land snail inadvertently led to the predation of native species, including George's kind. George passed away in 2019.
3. Future Spies
Snails may not be concerned with human politics, but the intelligence community certainly has an interest in them. The research division of the United States military (DARPA) is exploring ways to use mollusks as batteries and listening devices.
In 2012, a project successfully transformed a snail into a living battery. By harnessing the creature's blood sugar, researchers managed to power a battery-like implant, which generated a stable energy supply for several months.
While the snail produces an amount of power just shy of an AAA battery, the researchers have lofty ambitions. Their goal is to refine the technology-biology interface, so snails can generate enough energy to power microelectronics. This would allow the creatures to move around as living sensors and detectors on enemy walls, possibly even outfitted with miniature cameras.
Though turning snails into cyborgs may seem strange and potentially harmful, the mollusks continue to live near-normal lives. Their energy capacity relies on rest and food, with glucose levels recharging their battery-like implants.
2. Solar-Powered Slugs
As the name suggests, Elysia chlorotica is packed with chloroplasts. This extraordinary feature allows these sea slugs to photosynthesize, much like plants. Their green, leaf-shaped bodies make them resemble plants as well.
Native to the East Coast of the United States, this ability isn't an inherent trait. The slugs steal chloroplasts from algae. Once they have absorbed enough, they can go for months—up to nine—without eating, living off the energy they produce from the sun.
It is still a mystery how the chloroplasts stay intact and continue functioning within the slug's digestive system without being damaged. Similarly, the slug survives despite the harmful free oxygen radicals generated by the process of photosynthesis.
How do the plant parts and the animal parts even interact?
A detailed study is necessary to understand the symbiosis between the two. However, this rare animal-plant hybrid is incredibly difficult to find in the wild and struggles to survive in a laboratory setting.
1. The Pink Slug
Australia is known for its diverse and bizarre wildlife, and this was reaffirmed with the discovery of a new species of slug. This creature, scientifically identified as Triboniophorus aff. graeffei, is large and boasts a striking neon pink hue.
Stretching to 20 centimeters (8 inches) in length, this creature inhabits a single mountaintop. For years, scientists believed these slugs were part of the red triangle variety found along Australia's east coast. However, recent research has revealed that they are a distinct species, one that evolved specifically on Mount Kaputar.
These slugs are frequently found among red eucalyptus leaves, offering an explanation for their hot pink color. However, their camouflage doesn't entirely account for why the slugs spend so much time exposed. This striking hue might simply be an oddity of evolution.
Mount Kaputar was a secluded refuge in a desert for millions of years, and such isolated environments often give rise to peculiar species. Along with the giant pink slugs, this unique mountain is also home to species like the Kaputar cannibal snail and the Kaputar hairy snail.
