With thousands of stinging cells that can emit deadly venom from tentacles that can reach ten feet in length, the 50 or so species of box jellyfish have long been of interest to scientists and to the public. Yet little has been known about the evolution of this early branch in the animal tree of life.
In a paper published November 18 in the Proceedings of the Royal Society, NOAA researchers Allen Collins, Bastian Bentlage and Cheryl Lewis Ames of the Northeast Fisheries Science Center’s National Systematics Laboratory and colleagues from the University of Kansas, Pacific Biosciences Research Center in Hawaii and the University of Queensland in Australia have unraveled the evolutionary relationships among the various species of box jellyfish, thereby providing insight into the evolution of their toxicity.
“By determining the relationships among the different box jellyfish, some of which are capable of killing a healthy human, this study can help in the future development of antivenoms and treatments for their stings,” said Collins, a specialist in Cnidaria (pronounced nidaria), the phylum of animals that includes box jellyfish. “Researchers will now be able to make more informed choices about organisms for future venom studies, and make predictions on which species are likely to be of public health concern in addition to the known culprits.”
Beyond their toxicity, box jellyfish have other interesting characteristics.Some species have as many as 24 eyes, capable of sensing light and forming an image of their surroundings. Why they have complex eyes, how well they see, and what role vision plays in their mating and feeding behavior remain unknown.
Their vision may have something to do with the evolution of some extremely unusual mating behaviors in box jellyfish species. Jellyfish usually mass spawn, with males and females releasing sperm and eggs into the water without any physical contact. Study co-author Cheryl Lewis Ames has documented at least one box jellyfish species, Copula sivickisi (formerly Carybdea sivickisi), that exhibits a courtship of sorts where a male and female interact one on one to mate.
Box jellies, also called sea wasps, stingers or fire jellies, live primarily in warm coastal waters around the world. They are particularly well known in Australia, the Philippines and the rest of southeast Asia, but they also occur in Hawaii and in waters off the United States Gulf and East Coasts. Their toxicity varies among species and ranges from being completely harmless to humans to causing death within minutes after a sting.
Named for their box or cube-shaped body, these animals are members of Cubozoa, the smallest class of Cnidaria, animals ranging from sea anemones and corals to Portuguese man of war and true jellyfish, all of which possess stinging capsules known as nematocysts.
Using DNA extracted from tissue samples, the researchers used a number of genetic tests and analytical techniques to trace the evolution of the various species and their toxicity and to sort out misidentified species. The three-year study looked at dozens of specimens in collections around the world.
The Australian box jellyfish (Chironex fleckeri), the largest box jellyfish species, is considered the most venomous marine animal and its sting can be fatal. Its close relative, Chironex yamaguchii, has caused deaths in Japan and the Philippines. A much smaller species, Carukia barnesi, is the first species known to cause Irukandji Syndrome. Symptoms include severe low back pain, nausea, headache and vomiting, and sometimes “an impending feeling of doom”, but the syndrome is usually not life-threatening. Other box jellyfish species are now known to cause the same symptoms.
“Knowing who is related to whom among the box jellyfish will be very helpful in making predictions about species that are not well known,” said Collins, who began studying the evolutionary links of box jellyfish more than a decade ago. ”For example, we may not know how serious the sting is from a particular jellyfish species, but if we know its close relatives cause Irukandji Syndrome, than it is highly likely that this species also causes the syndrome. Similarly, there is an antivenom for Chironex fleckeri, whose closest relative is Chironex yamaguchii. It may be that the antivenom will work against stings from this species as well.”
The study results indicate that the venoms of box jellies may contain a novel and unique family of proteins. However, further toxicological tests and many more specimens are needed to resolve questions about venom and to develop antivenoms and treatments for box jellyfish stings.Cnidarians are difficult to study because their relatively simple structure makes it hard to compare to other groups of organisms. Few specimens are available in natural history museums or laboratories preserved for biological and molecular study, and fossil records are rare.
NOAA’s National Systematics Laboratory, located in the Museum of Natural History at the Smithsonian Institution, is part of the Northeast Fisheries Science Center but serves as the taxonomic research arm of NOAA's Fisheries Service as a whole. The laboratory describes and names new species, and revises existing descriptions and names based on new information, of fishes, squids, crustaceans, and corals of economic or ecological importance to the United States. Because some important species are highly migratory and many exotic species are introduced into U.S. waters or markets, the laboratory's research is worldwide. Major products of this research are worldwide and regional taxonomic publications and identification guides.
NOAA Fisheries Service is dedicated to protecting and preserving our nation’s living marine resources and their habitat through scientific research, management and enforcement. NOAA Fisheries Service provides effective stewardship of these resources for the benefit of the nation, supporting coastal communities that depend upon them, and helping to provide safe and healthy seafood to consumers and recreational opportunities for the American public.
NOAA understands and predicts changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and conserves and manages our coastal and marine resources.
Shelley Dawicki | EurekAlert!
Unique genome architectures after fertilisation in single-cell embryos
30.03.2017 | IMBA - Institut für Molekulare Biotechnologie der Österreichischen Akademie der Wissenschaften GmbH
Transport of molecular motors into cilia
28.03.2017 | Aarhus University
The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.
To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
30.03.2017 | Physics and Astronomy
30.03.2017 | Studies and Analyses
30.03.2017 | Life Sciences