ANSWER: 3
Explanation:
Three clusters of bacteria having no phylogenetic relationship to any other bacteria have been discovered by chance by Indian scientists. Discovery occurred during the LOHAFEX experiment in the Southern Ocean, Antarctica which aimed at raising CO sequestration through ocean iron fertilisation as part of global warming mitigation. LOHA means iron in Hindi and Fex stands for fertilisation. Director, National Institute of Oceanography, S. W. A. Naqvi was the principal investigator in the experiment. Authors pointed out the oceans are a major source and carbon sink with marine phytoplankton fixing up to 40% CO. The three clusters discovered were as following. First was related to class of bacteroidetes while the second and third belonged to firmicutus. Distinct feature of the three clusters was the differentiated response for presence of iron in the ocean. Organisms in cluster 1 did not respond to iron levels while those in cluster 2 increased with additional of iron and those in cluster 3 disappeared with the addition of iron. Hence clusters 2 and 3 could be indicators of iron in the ocean waters.