In the depths of the ocean, near the South Sandwich Islands, a remarkable marine creature has been filmed. This is not an ordinary spider, but a sea spider, an organism that astonishes with its impressive size.
These sea spiders, or pycnogonids, are distant relatives of land spiders. With leg spans reaching up to 20 inches (51 cm), they far surpass the largest land spiders. This impressive size is attributed to abyssal gigantism, a phenomenon where deep-sea creatures become much larger than their shallow-water counterparts.
Abyssal gigantism is particularly prevalent near the poles, where freezing temperatures favor a slower metabolism. This allows these creatures to reach surprising sizes. Sea spiders are described as both abundant and large in these polar regions.
There are about 1,500 known species of sea spiders, but many more likely remain to be discovered. These creatures inhabit oceans worldwide. The largest specimens are generally found at depths between 7,200 and 13,100 feet (2,200 to 4,000 meters).
Unlike land spiders, sea spiders do not spin webs or dig burrows. Instead, they use a specialized tubular mouthpart called a proboscis to suck up their prey, such as sea anemones, jellyfish, and other invertebrates.
This recent video was captured by remotely operated vehicle pilots during the South Sandwich Islands expedition by the Schmidt Ocean Institute. This mission aims to locate and describe new species in these icy waters. According to the institute, only 10% of ocean life has been discovered to date.
What is abyssal gigantism?
Abyssal gigantism is a biological phenomenon where creatures living in the deep sea reach sizes much larger than their shallow-water counterparts. This phenomenon is often observed in species living at extreme depths, where environmental conditions are radically different from those at the surface.
Scientists attribute this gigantism to several factors, including cold temperatures and high pressure in the deep sea. These conditions allow for a slower metabolism, which can favor greater growth. Additionally, in the depths, food resources are scarce and scattered, which can also encourage larger size to increase survival chances.
Abyssal gigantism is particularly widespread in polar regions, where temperatures are even lower. This explains why the largest specimens of sea spiders and other marine creatures are often found in these areas. This phenomenon remains a subject of study for marine biologists, who seek to understand how these extreme conditions influence species evolution.
How do sea spiders feed?
Sea spiders have developed a unique feeding method adapted to their marine environment. Unlike land spiders that spin webs or dig burrows, sea spiders use a specialized mouthpart called a proboscis.
This proboscis is a flexible and extendable tube that allows them to suck up the fluids of their prey. Sea spiders primarily feed on soft marine creatures like sea anemones, jellyfish, and other invertebrates. Their feeding method is particularly effective in the deep sea.
This adaptation shows how sea spiders have evolved to survive in such a hostile environment. Their ability to feed in this manner allows them to make the most of available resources, even in the most extreme conditions. This also illustrates the diversity of feeding strategies in the marine world, where each species must find unique ways to survive and thrive.