Recent research, published in Current Biology, has uncovered intriguing insights into their cognitive abilities that challenge the notion that jellyfish lack intelligence.

Moon jellyfish, ethereal and fair,

Drifting through the depths, a ballet in air.

Translucent bodies, a delicate grace,

Invisible currents guide your embrace.

Moonlit tendrils, trailing behind,

A dance of beauty, nature's design.

Gentle pulsations, rhythmic and slow,

In the tranquil sea's ebb and flow.

Mysteries hidden in your gelatinous form,

A testament to life's diverse norm.

Animals are endowed with the capacity to repair injuries. Some animals simply heal the wound, whereas others are able to regenerate lost parts.

A new study now documents yet another and previously unidentified strategy of self-repair, where moon jellyfish respond to injuries by reorganizing existing parts, and rebuilding essential body symmetry, important for them to stay balanced as they travel around the ocean, without regenerating what is lost.

Researchers have known that an animal swimming parallel to a solid surface receive a subsequent boost in performance, thus allowing them to utilise less energy when moving around. 

 

Studies have quantified this into a 25 percent increase in speed and a 45 percent increase in thrust when swimming near a solid surface. 

However, the jellyfish does not swim near the seafloor or seawalls. How does it get named the "world's most efficient swimmer"?

Apparently, it does so by creating a "virtual wall."

In some tropical waters like the Florida Keys mangrove forests, for snorkellers to stay safe, it’s not enough to not touch anything. It may not be a good idea to enter the water in the first place.

That’s because sometimes it seems that the water itself can sting, causing rashes on a snorkeller's skin.

The real culprit is not some mutant strain of water molecules. Rather, it is a species of upside-down jellyfish that lives on the ocean floor. Called Cassiopea xamachana, this jellyfish can also be found in places like the Caribbean Sea and the Gulf of Mexico.

In some tropical waters like the Florida Keys mangrove forests, for snorkellers to stay safe, it’s not enough to not touch anything. It may not be a good idea to enter the water in the first place.

That’s because sometimes it seems that the water itself can sting, causing rashes on a snorkeller's skin.

The real culprit is not some mutant strain of water molecules. Rather, it is a species of upside-down jellyfish that lives on the ocean floor. Called Cassiopea xamachana, this jellyfish can also be found in places like the Caribbean Sea and the Gulf of Mexico.

After combing through more than 2,000 articles and conducting a systematic review of the evidence for the use of heat or ice in the treatment of cnidarian envenomations, the team concluded that the majority of studies to date support the use of hot-water immersion for pain relief and improved health outcomes.

Irukandji jellyfish are highly venomous and dangerous, hospitalising up to 100 people annually in Australia.

Irukandji syndrome can manifest itself as severe abdominal pain, back, limb or joint pain, nausea and vomiting, profuse sweating and agitation. The patients may also experience numbness or paraesthesia. More severe reactions to Irukandji stings can include hypertension and tachycardia, and in extreme cases, stroke and heart failure. The symptoms last from hours to weeks, and victims usually require hospitalisation.

Increased speculation and discrepancies about current and future jellyfish blooms by the media and in climate and science reports formed the motivation for the study.

The key finding of the study shows global jellyfish populations undergo concurrent fluctuations with successive decadal periods of rise and fall, including a rising phase in the 1990s and early 2000s that has contributed to the current perception of a global increase in jellyfish abundance.