The Evolution of Plants and how they came to be

To those interested in The Evolution of Plants and how they came to be, the following post is dedicated to you.

First, let us briefly characterize the main groups of the plant kingdom. Focusing on extant lineages we can see the kingdom is divided into two main groups. Those groups being Nonvascular Plants (Bryophytes: Liverworts, Mosses, and Hornworts) and Vascular Plants (Seedless and With seed including Gymnosperms and Angiosperms. ). They are called vascular due to cells joined into tubes that transport nutrients and water throughout the body. The Ten Phyla of Extant Plants approximates the number of known plant species to be around 300,000. To see pictures of Bryophytes and Gymnosperms you can go back to my Hortus post.

How did plants come to be?

In Figure 29.6 it is seen that all Plants came from a common Ancestor of Green Alga, a group composed of many unicellular species and small colonial species. With the appearance of spores, early plants arose approximately 470 million years ago. Not just the appearance of any type of spore but one with a different chemical composition than those of algae or fungi. One plant with a larger plant structure than most plants 425 million years ago is the Cooksonia sporangium (The guide is pointing at it on the right side). The Cooksonia, Rhynia, and Zosterophyllum are the main ancestral plants scientists believe to have given rise to the incredible diversification depicted in living plants today.

Phylogenetic Tree of how Vascular and Nonvascular plants came to be

Table 29.1 showing Ten Phyla and the Number of Known Species within each
Biology a Global Approach by Campbell

Until next time,

Sol

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