Science doubles ocean RNA virus phyla

Scientists did not announce a brand-new 2026 discovery here. The claim circulating again on social media traces to an April 7, 2022 Science paper that analyzed roughly 28 terabases of Global Ocean RNA sequences and described a major expansion of the known marine RNA virosphere. (pubmed.ncbi.nlm.nih.gov) The core finding was large. The researchers reported about 5,500 previously unknown RNA virus species in ocean samples collected around the world and proposed five new phyla, which at the time doubled the number of recognized RNA virus phyla. (pubmed.ncbi.nlm.nih.gov) (science.org) The work came from an international team led in part by Matthew Sullivan of Ohio State University and drew on the Tara Oceans expedition and related Global Ocean datasets. A second Science paper published in June 2022 used the same broader dataset to map the diversity and ecological footprint of marine RNA viruses from pole to pole. (pubmed.ncbi.nlm.nih.gov) ### Where did the “doubling phyla” line come from? Science’s April 2022 paper, “Cryptic and abundant marine viruses at the evolutionary origins of Earth’s RNA virome,” is the source of the line now being reposted. PubMed’s abstract says the team analyzed global ocean RNA data to expand RNA virus catalogs and taxonomy and to investigate evolutionary origins and marine biogeography. (pubmed.ncbi.nlm.nih.gov) Ohio State’s summary of the paper said the team combined machine-learning analysis with evolutionary trees and identified 5,500 new RNA virus species. That release also said the work reshaped understanding of how these viruses evolved. (hal.science) ### What exactly did the researchers find in the ocean? The study focused on RNA viruses, which are best known publicly for human and animal disease but are also common in marine ecosystems. The researchers screened oceanic metatranscriptomic data for genes encoding RNA-dependent RNA polymerase, a hallmark enzyme used by many RNA viruses. (pubmed.ncbi.nlm.nih.gov) The resulting catalog included thousands of candidate marine RNA viruses and several lineages that did not fit neatly into the previously recognized phyla. EurekAlert’s summary of the paper said some of those lineages appeared to represent a “missing link” in RNA virus evolution. (news.osu.edu) ### Did the paper literally double all known RNA viruses? No. The paper’s “doubling” referred to phyla, a high taxonomic rank, not to the total number of virus species. Before the study, five RNA virus phyla were broadly recognized within the kingdom Orthornavirae; the team proposed five more from the marine data. (pubmed.ncbi.nlm.nih.gov) That distinction matters because the species count and the phylum count are different claims. The species figure was about 5,500 new RNA virus species, while the taxonomy claim was that five proposed phyla doubled the previously recognized set. (eurekalert.org) ### Was the taxonomy accepted without dispute? A 2023 critique in Virus Evolution challenged part of the original interpretation. Robert Edgar wrote that the Tara Oceans study had proposed five new RNA virus phyla, but his reanalysis found that contigs assigned to those new phyla made up only 2.8% of the study’s classified contigs and that known phyla dominated the data. (smithsonianmag.com) That means the underlying 2022 discovery of many new marine RNA viruses is well documented, while the claim that some of the newly proposed phyla were dominant in the oceans was later disputed by another researcher. (news.osu.edu) The critique addressed classification and abundance, not the existence of a large trove of newly described marine RNA virus sequences. ### What happened after the first paper? Science published a second paper in June 2022, “Diversity and ecological footprint of Global Ocean RNA viruses,” that used the Global Ocean dataset to describe four ecological zones and latitudinal and depth patterns in marine RNA virus diversity. (academic.oup.com) As of September 2, 2026, the post resurfacing this finding points back to the April 2022 Science study rather than a newly published paper. Readers looking for the original result should look to the April 8, 2022 issue of Science and the companion June 2022 ecology paper by the same broader research effort. (academic.oup.com) (pubmed.ncbi.nlm.nih.gov) (science.org)