Bryophytes and ferns

Bryophytes are usually small in size, and most of the members of the phylum are dependant on water or moist surroundings to survive(Raven 1999). The reason that they rely so heavily on moisture in their environments is because they are lacking a vascular system. Bryophytes are some of the oldest and most primitive plants still extant on earth, and since they are unable to utilize xylem and phloem like vascular plants to transport water, food, and minerals throughout the plant body, they must remain small and live in a very moist environment ( Shaw et al 2003).

A very important distinction between bryophytes and other plants, other than the fact that they have no vascular systems, is that all bryophytes reproduce by the exchange of spores rather than producing flowers or seeds (Steel et al 2004).

In fact, much scientific evidence suggests that bryophytes are among the very first examples of modern plant life. Bryoph

ytes appear to be in a transitional stage of the evolutionary chain as we understand it. They share many common features of aquatic algae and other simple plant-like water organisms, as well as precursors to the more evolved land plants such as the gymnosperms and angiosperms. Therefore, they are either a common ancestor of modern land dwelling plants- one that probably split off and evolved separately throughout the millennia (Randerson 2003). In 2003, a discovery in 450 million year old rocks seems to have answered the question. Fossilized fragments of plant matter, less than half a millimeter wide, were discovered(Randerson 2003). This predates earlier predictions of the beginning of plant life by 25 million years. The fossils appear to be sporangia, the structure in which spores develop in bryophytes, and they resemble those present in modern liverworts (Randerson 2003).

Bryophytes are also extremely important to the environment, both acting as a sort of filter, and also harboring and feeding a multitude of organisms. Some research indicates that bryophyte communities are at least as abundant and diverse in a forest ecosystem as the higher plant life’s (Szczepaniak and Biziuk 2003). Besides the apparent evidence that bryophytes are as evident and important on their own, there have also been studies that have attempted to show the overall biological importance of the different species. One study, by Steel et al, seems to say what most other studies are indicating- the overall s

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