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5. The First Conifers: Pioneers of the Gymnosperms
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The conifers emerged as a new category of plants changing the prehistoric scene when the Carboniferous epoch gave way to the Permian. Originally appearing over 300 million years ago, these plants marked a major evolutionary change in plant biology. Among the early gymnosperms, a class of seed-bearing plants that would eventually rule terrestrial environments for most of the Mesozoic epoch, were conifers.
Early conifers like Walchia and Voltzia were somewhat different from their present counterparts. Little, shrub-like plants with scale-like leaves spirally grouped around the limbs. Though small, these early conifers had several improvements that would be vital for their success. Among these were the cone, a specifically designed shelter for seeds. This adaptation gave conifers a competitive edge over many of their spore-producing contemporaries since it let them reproduce more effectively under drier conditions.
Conifers started to flourish as the Permian period's climate become drier and cooler near its end. Their capacity to save water by means of specialised leaf structures and effective vascular systems helped them to occupy regions that were turning hostile to the Carboniferous forest moisture-loving plants. As they dispersed over the supercontinent Pangaea and developed into a great range of forms, this adaptability would be really helpful in the next ages.
The conifers' ascent signalling a major change in the makeup of Earth's forests. Many of the old plant groupings that had dominated during the Carboniferous started to be outcompessed as these gymnosperms grew more common. Conifers and their allies spread in range and diversity while the once-mighty scale trees and seed ferns progressively disappeared. This shift prepared the ground for the gymnosperm-dominated environments that would define most of the Mesozoic period, including dinosaur age.
