Original: Swampy habitats like shallow wetlands, coastal lagoons and large brackish river deltas also existed at this time, and there is much to suggest that this is the kind of environment in which the tetrapods evolved.
Simplified: Early tetrapods have been found in swampy habitats like shallow wetlands, coastal lagoons, brackish river deltas, and even shallow marine sediments. There is much to suggest that these are the kind of environments in which the tetrapods evolved.