Understanding Echinoderms as Part of Marine Biology

Echinoderms are a phylum of marine organisms. They are generally characterized as invertebrates that have hard, internal calcium based skeletons, a water vascular system, and a five-rayed radial symmetry. Some examples of echinoderms are starfish, sand dollars, sea urchins, sea cucumbers, and brittle stars. The importance of echinoderms goes past the aesthetics that they bring to marine ecosystems. Echinoderms also have economic, ecologic, scientific, nutritional and medicinal purpose. They do so much not only for marine ecosystems, but also play a large role in the lives of humans.

The first and foremost action that echinoderms perform in the world is ecology based. Many echinoderms play critical roles in marine ecosystems and without them most of the ecosystems would be drastically altered, in most cases with calamitous consequences. For instance, pisaster ochraceus, or “the purple sea star” is a keystone species in many intertidal zones. Meaning, that without them there, the ecosystems fail, which was seen in a study done where they were removed from their natural habitat and a series of mussel beds died and didn't reproduce as rapidly. Another example of would be the purple sea urchin. The purple sea urchin is also found in intertidal zones and acts as a buffer for coral reefs. They're also a major food source not only for marine organisms, but humans too. The gonads of both male and female sea urchins are culinary delicacies in many parts of the world.

In addition to the life they bring to marine ecosystems, echinoderms also have a geological system. In geology, echinoderms are mainly used as index fossils, meaning that they help determine how old rocks are. The fossils found can match up with specific types of organisms found in the fossil record. Many echinoderms are used in this fashion to help determine the paleoecology of a given area. Paleozoic fossils have the potential to contain a lot of important data. This relates back to the idea that echinoderms provide a lot of necessary resources for both the organisms in their habitats and for humans as well.

Another way that echinoderms serve humans in society is as a food source. As distasteful as it may sound, some echinoderms are used as a food source. As mentioned earlier, sea urchins have real economic value along with sea cucumbers. Sea cucumbers are eaten throughout Asia because of certain theories about them such as, they're an aphrodisiac. The problem that lies with sea cucumbers being on the market is that they get over fished. As stated earlier, when echinoderms get removed from their habitat bad things can happen. Sea urchins are also a delicacy in Japan and are hunted for their succulent innards. Unlike, sea cucumbers, the sea urchins aren’t being over fished. Surprisingly there is more stability in urchin economies than cucumber economies. Nonetheless, both have great economic value and once again contribute to society in a fascinating way. Echinoderms being used as a food source relates back to the idea that they can be used for multiple things, and they have such value not only to their ecosystems, but to humans as well.

Echinoderms also help humans make many advancements in the field of genetics. Over that past couple of decades, echinoderms have been studied in minor ways in an attempt to determine their use genetically. In the last couple of years, the main echinoderms that arrived at the forefront are purple sea urchins, asterinidae, and asterias. The purple sea urchin genome is estimated to encode approximately 23,00 genes. Many of the genes were assumed to be “vertebrate innovations” or were only known from groups outside the deuterostomes. Surprisingly the sea urchin genome compares to our own and other deuterostomes a group to which both urchins and humans belong. The purple sea urchin and humans share about 7,700 genes. Many of these genes have to do with sensing the environment which is ironic seeing as how the urchin doesn't have a brain. The other two species, asterinidae and asterias, similar to the sea urchin, share some genetic code with humans, but it isn’t nearly as striking as the purple sea urchin. In conjunction with genetics, echinoderms also have medicinal purposes. For instance, some toxins found in sea cucumbers slow down the growth rate of tumor cells, so they have been targeted for a lot of cancer research. The plethora of uses that echinoderms have is amazing.

In conclusion, it is apparent that echinoderms have multiple uses to both humans and organisms within their specific ecosystems. It is fascinating how versatile the echinoderms are, from their genetic and medicinal use, to their geological use. Overall it is safe to say that echinoderms should be valued more in society because of their major contributions to the lives of humans and the marine ecosystem as a whole.