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Comparison of honeycomb-like patterns of ridges and tufts on surfaces of microbial mats from the 3.48 Ga Dresser Formation, the 2.9 Ga Pongola Supergroup, and El Bibane, Tunisia (modern). The ratio between three generations of compartments is approximately 4:1 for each of the three modal peaks across all examples studied. Compare the structures shown in Fig. 9D. Color images available online at www.liebertonline.com/ast
