Cambrian ocean world. Ancient sea life of North America / Кембрийский океанический мир. Древняя морская жизнь в Северной Америке

Imagine a tropical morning on the ocean. The air is comfortably warm and moist, but it is not muggy or hot; scattered clouds are slightly pink with the last colors of dawn as the sun glares orange, low on the eastern horizon. The ocean on which you are fl oating is deep blue, and the surface waves are only a few feet high. From all appearances, it could be offshore Hawaii. Pitching lightly on a large, infl atable dinghy, we prepare technical diving gear and extra tanks and notice that there is no land in sight; we are probably at least several tens of miles from the nearest land beyond the horizon to the south, but how far we can’t tell. We are going deep, and this type of diving requires special training, equipment, and experience. As the sun climbs in the sky we notice that the sea surface color transitions to a lighter blue away to the south and west. <...>