By Gurpreet Singh | October 8, 2025
Often called “blue-green algae,” cyanobacteria produced Earth’s first oxygen, transforming the atmosphere and paving the way for all complex life forms.
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Surviving for over 450 million years, horseshoe crabs outlived dinosaurs. Their blue blood helps modern medicine detect bacterial contamination in vaccines.
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The nautilus has remained unchanged for 500 million years, using jet propulsion and a coiled shell to navigate deep ocean waters.
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Ancestors of all land vertebrates, lobed-finned fish evolved 390 million years ago and still swim in ancient, oxygen-poor waters today.
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Formed by cyanobacteria, stromatolites date back 3.5 billion years. These layered structures still grow today in Australia and the Bahamas.
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These ancient crustaceans have barely evolved in 220 million years, hatching from dormant eggs that can survive extreme droughts.
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Microbial mats resemble Earth’s earliest ecosystems and continue shaping planetary chemistry.
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Coral colonies have built reefs for 500 million years, forming vibrant underwater cities that nurture countless marine species.
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The tuatara, a reptile native to New Zealand, is the last survivor of an ancient lineage dating back 200 million years, predating modern lizards.
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Mosses are existing for over 450 million years. They thrive in extreme environments, from Arctic tundras to tropical rainforests.
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