The Evolution of Plants
Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: CHAPTER IV THE EVOLUTION OF THE SEED-PLANTS The Cycadophytes of the Secondary period, as we saw in the last chapter, were very highly organised plants, their dominant family, the Bennettitese, far surpassing the modem Cyc- adacese and rivalling the Angiosperms themselves. This superiority of the old to the new might seem surprising if we took the obvious view that Evolution is a regular progression from the simple to the complex. This, however, is far from being the case; Evolution is to be compared to the successive waves of a flowing tide, rather than to the steady rise of a calm river. In Mesozoic times the Cycadophytes formed the wave that rose highest, but soon that wave receded, and another followed and rose higher still. The Cycadophyta, hi fact, were then the dominant class; there was nothing above
...them; they were the best thing in the way of Flowering Plants that their age had produced; from their triumphant success, overspreading all parts of the world, we cannot doubt that they were perfectly suited to the conditions then prevailing. Later on, the conditions became morecomplex, a change in which the increasing multiplicity of insect life was no doubt a chief factor. The Angiosperms, arising probably as an offshoot from the Cycadophyte stock, thus found their opportunity and rapidly fitted themselves into the numberless new places that the changing world presented to them. The higher members of the old family were no longer able to compete with their more enterprising younger line; the ancient race decayed, and, for all we know, became extinct; the less advanced Cycads did not come into such direct competition with the ascendant race, and have survived, in moderate numbers, as the recent Cycadacese. A Mesozoic genus of Cycads, NUssonia, of uncertain family, i...
MoreLess
Write Review:
Guest
Read Also
User Reviews: