Fern spores on the underside of a frond
When plants like moss first began to grow outside the water, about 540 million years ago, they needed a way to reproduce themselves that didn't depend on water so much. Some of these plants evolved to be able to produce spores.
To make spores, plants begin by dividing some cells using meiosis to produce sperm and egg cells. Then
When more complex plants like ferns evolved, they also used spores to reproduce. But spores need to land on wet dirt, or they'll die. In order for plants to move away from the edge of streams and ponds, they had to evolve a way of reproducing that didn't involve water - the seed.
To find out more about seeds and spores, check out these books from Amazon.com or from your library:
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