Sea spiders have been on the planet for at least 425 million years and deep-sea researchers just observed bioluminescence for the first time\u00a0<\/p>\n
When scientists spend a month studying the Australian deep sea, they discovered that two giant sea spiders living in the ocean\u2019s abyssal zone have light-up legs.\u00a0<\/p>\n
The researchers were surveying waters between 1,006 and 4,977\u202fmetres deep off Australia\u2019s east coast in May and June 2017\u202fwhen they found that two species of Pycnogonida (sea spiders) had glow-in-the-dark legs. The discovery is published in\u00a0Deep Sea Research Part I: Oceanographic Research Papers<\/a>.<\/p>\n \u201cThe Pycnogonida, or sea spiders, have a fossil record extending back to the Silurian period, approximately 425 million years ago,\u201d write the authors in the study. These creatures are categorised within a group called Chelicerata, \u201cwhich includes animals such as scorpions, horseshoe crabs<\/a> and spiders among others,\u201d they add.\u00a0<\/p>\n Pycnogonids can be found all over the world from shallow coastal waters to the deep-sea. There are more than 1,400 known species currently living on Earth with more being discovered all the time.\u00a0<\/p>\n Experts are also finding out more about what these strange beings can do. For example, this is the first time scientists have seen\u00a0Colossendeis tasmanica\u00a0and\u00a0Colossendeis minor\u00a0glowing in the dark. The two species were discovered in 2007 and 1893 respectively.\u00a0<\/p>\n According to the study, this doubles the number of known bioluminescent sea spiders from two to four.<\/p>\n Seeing the critters glimmer in the deep sea doesn\u2019t necessarily mean they are creating the light \u2013 they could be carrying bioluminescent organisms on their bodies.\u00a0<\/p>\n