PREVIEW

Researchers from the University of Hawai?i at Manoa have resolved a longstanding mystery of the deep by discovering how giant sea spiders reproduce. The reproduction of giant sea spiders in Antarctica has been largely unknown to researchers for more than 140 years, until now. Sea spiders, or pycnogonids, are a group of spider-like invertebrates found in species around the world. Most species are smaller than a fingernail but some Antarctic species have leg spans of more than one foot! They are of special biological interest as an example of “polar gigantism” whereby some organisms in polar regions grow to much larger sizes than their relatives in warmer climates. Outlining the mysterious nature of the ocean arachnids, Professor and lead researcher Amy Moran said "In most sea spiders, the male parent takes care of the babies by carrying them around while they develop. What’s weird is that despite descriptions and research going back over 140 years, no one had ever seen the giant Antarctic sea spiders brooding their young or knew anything about their development” By diving under the ice, her team hand-collected groups of giant sea spiders that appeared to be mating and transported them to tanks for observation. To their amazement, two different mating groups produced thousands of tiny eggs. Instead of carrying the babies until they hatched. One parent spent two days attaching the eggs to the rocky bottom and hiding them before they developed for several months and hatched hence why their development had remained a mystery!