A patch of Mediterranean seagrass could be up to 200,000 years old making it the oldest living creature on Earth, according to Australian researchers. The super-ancient patch of Neptune grass, a species of seagrass, spans 2,000 miles from Spain to Greece. Researchers previously estimated that several plant colonies like seagrass could live for thousands of years. While no individual part of a colony is alive for more than a fraction of the plant's life, these colonies contain genetically identical clones that propagate and reproduce asexually for thousands of years.