After years of research, scientists have finally uncovered the mystery surrounding the unique way in which big Antarctic sea spiders take care of their eggs. Unlike other sea spiders that carry their eggs around until they hatch, the giant Antarctic sea spider (Colossendeis megalonyx) attaches its hundreds of tiny eggs to the rocky seafloor, according to a new study.
Sea spiders are marine arthropods found in oceans around the world. They have eight extremely long, thin legs that give them a resemblance to terrestrial daddy longlegs spiders (family Pholcidae), although they are not related.
While most sea spiders only grow up to an inch in length, those living in polar regions, like C. megalonyx, can have leg spans of up to 20 inches (51 centimeters) – a phenomenon known as ”polar gigantism” due to their much larger size compared to sea spiders in warmer climates.
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Sea spiders are among the few marine arthropods in which the males take on the role of caring for their offspring. “In most sea spiders, the male parent takes care of the babies by carrying them around while they develop,” said lead author Amy Moran, a professor at the University of Hawai’i’s School of Life Sciences at Manoa. While research on the reproductive strategies of sea spiders dates back 140 years, Moran noted that the brooding behavior of three out of the 11 recognized families of sea spiders, including the Collossendeidae family to which C. megalonyx belongs, had never been observed.
To determine how these sea spiders care for their eggs, divers ventured into the icy waters of McMurdo Sound in Antarctica and collected C. megalonyx individuals that appeared to be in mating groups – identified by individuals stacked on top of each other. The pairs were then brought to the research facility McMurdo Station, where they were kept in tanks for observation, as described in the study published on February 11 in the journal Ecology.
This is fascinating! I never knew such creatures existed in Antarctica. Can’t wait to read more about this discovery.