Word: devonians
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...fishapod was among the pioneering organisms to take advantage of an ecological frontier--the marshy floodplains of large rivers--that opened between 410 million and 356 million years ago during the Devonian period, known as the Age of Fishes. Early in the Devonian, the continents were mostly masses of bare rock with just a fringe of plants "no taller than your ankle," as Daeschler puts it, growing along the wet margins of rivers and streams. By the late Devonian, however, thick vegetation had taken hold in marshes, fens and floodplains, and mosses, ferns and trees had coalesced into the world...
...depends on how and when the genes are turned on by a segment of DNA that acts like a switch. Fish have a version of that switch too. For example, Zebrafish (ray-finned fish that split off from the lineage that led to lobe-fins early in the Devonian) have only part of the sequence, whereas coelacanths (lobe-fins closely related to lungfish) have a lot more of it. And the fishapod, presumably, had even more...
Proterozoic ? First shellfish and corals Cambrian Ordovician ? First fsh Silurian ? First land plants Devonian ? Tiktaalik ? First tetrapods Carboniferous ? First reptiles ? First mammal-like reptiles Permian Triassic ? First dinosaurs ? First mammals Jurassic ? First birds Cretaceous ? First flowering plants Cenozoic ? First horses...
...fossil, called Tiktaalik roseae, was found in rocks from the Devonian Age, which date back 375 million years. The organism’s gills identify it as a fish, but it lacks the piscatorial characteristic of a neck that is connected to the shoulder girdle, Jenkins said. The fish’s front fin contains identifiable wrist bones and features that resemble fingers, he added...
...report in Science suggests that 370 million years ago, during the Late Devonian period, a comet or asteroid caused an even greater catastrophe, one that wiped out fully 70% of all marine species on earth. American and Belgian scientists have found tiny glass beads just .3 mm (.004 in.) across, embedded in underground sediments in Belgium. The beads, called microtektites, are thought to be caused when silicon and other minerals melt and then cool following either a volcanic eruption or a high-speed impact. The chemical composition of these beads seems to point much more convincingly to an impact...