### Decoding a Century-Old Enigma: Scientists Unravel Antarctic Sea Spiders’ Parenting Puzzle

The enormous Antarctic sea spider (Colossendeis megalonyx) has intrigued ecologists with its parenting behavior for over a century. However, US researchers believe they have unraveled this mystery after conducting an investigation beneath the ice.

Sea spiders, which belong to the order Pantopoda, are marine arthropods distinct from land spiders of the order Arachnida. These creatures, with 8 to 12 legs that facilitate respiration and digestive systems that aid in blood circulation, showcase a rare form of parental care in nature.

Professor Amy Moran from the University of Hawaii at Mānoa’s school of life sciences, the lead author of a paper in Ecology, explains that male sea spiders typically nurture their offspring by carrying them during the developmental stages. Despite historical records dating back 140 years, observing the giant Antarctic sea spiders tending to their young remained an enigma until now.

While most sea spider species are small, measuring a few millimeters, the giant Antarctic sea spiders can reach up to 30cm in diameter due to their elongated legs, a phenomenon known as “polar gigantism.”

During an Antarctic expedition near McMurdo Station, Moran and her team dove beneath the ice to study mating sea spiders. They observed mating pairs releasing egg clouds, with one parent, presumed to be the male, securing the eggs to rocks at the tank’s base. The eggs remained concealed for months beneath algae cover, camouflaging them effectively.

After a period, the eggs hatched into tiny larvae, revealing a rare sight that had eluded researchers for years. This unique opportunity to study these creatures up close in Antarctica provided invaluable insights previously unknown to science.

The research team’s discoveries shed light on the fascinating world of sea spiders, highlighting their extraordinary parental care and development processes. This groundbreaking research was made possible through the support of the Minderoo Foundation for the Ultramarine project, focusing on marine research and innovation.

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