2. Antarctic sea spiders’ legs can grow to span the width of your face.
Like all marine invertebrates, Antarctic sea spiders have a body composition that matches the ocean’s salinity, which means that as long as the water around them remains in liquid form, they cannot freeze. Antarctic sea spiders are considerably larger than temperate sea spiders, having an average leg span of 29.5 inches! It is thought that this polar gigantism occurs due to the heightened levels of oxygen found in cold water. Sea spiders are bizarre. They feed by sticking their proboscis into soft animals and sucking out the juices. These sea creatures do not have much room in their bodies, so their guts and reproductive organs reside in their spindly legs. They also do not have gills or lungs. To cope, they absorb oxygen through their cuticle or shell-like skin.