two and that each individual's virum has a slightly different makeup of different types of viruses studies of metagenomic data or the dna sequences found in environmental samples both within and outside organisms bodies have helped researchers shed light on the makeup of the viral it consists of viruses that infect bacteria viruses that infect other microscopic organisms and viruses that infect human cells as part of the microbiome evidence suggests that the virum plays a major role in our health like recent studies of the human virus have shown that different viruses live in different parts of the body like the urinary tract gastrointestinal tract oral cavity blood and lungs and while we don't fully know yet what they're doing there we do have some clues for example a healthy mouth has plenty of viruses helping keep the oral microbes in check increased presence of some viruses that naturally colonize the oral cavity and respiratory tract can throw that balance off and lead to various diseases including periodontal disease but even with interest in the virum on the rise and papers piling up we don't really understand it yet one thing seems to be clear the virum and its makeup can definitely influence our health so even if you could just poof away all viruses in your body right now you might want to think twice and humans aren't the only animals with virums that vary in their different tissues all kinds of animals plants and other organisms are known to have them not only do viruses play a role in the health of organisms they're also thought to shape the biosphere viruses are everywhere in earth's ecosystems in big numbers and one of the major impacts of viruses in the environment is in how their presence affects communities of bacteria based on what researchers have learned so far their significance is most obvious in the ecology of oceans they constantly shape the diversity of natural bacterial populations under the sea in a very big way they're present in our oceans in such astronomical numbers it's estimated that they would stretch from here past the next NUMBER_TOKEN galaxies if laid end to end every second hundreds of trillions of viral infections occur in the ocean every day they're thought to kill around NUMBER_TOKEN percent of all marine bacteria which just saying is a lot and that turns out to be a huge part of how nutrients and energy cycle in the ocean for instance all those dead bacteria are thought to release enough iron to support the needs of phytoplankton the composition of earth's atmosphere also hinges on the shuffling of all that organic material from viral killing activity in the ocean to the tune of three gigatons of carbon sequestered every year and this is a very abridged list of viruses oceanic activity virus's role in soil isn't as well studied as in the ocean but the importance is clear one gram of soil can house up to NUMBER_TOKEN billion viruses and they can be present in bigger numbers than bacteria studies suggest that viruses may have a major impact on carbon and nutrient cycles on land just as they do in the ocean they're also a fount of genetic diversity in both the soil and the ocean a lot of what we've talked about gets to the importance of viruses for organisms in ecosystems right now but here's where we need to remember what every time travel show and movie says about changing things in the past don't do it even if it seems like a great idea in your head basically if viruses did co-evolve with life forms then they're sort of part of life on earth
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