The first to diverge from the algal ancestor were Lycophyta, which evolved from zosterophyllophytes. Lycophyta have microphylls, which are leaves that began as outgrowth of stem tissue which developed into a single vascular strand. Their sporangia are on sporophylls, leaves specialized for reproduction. This is obviously a step in terms of evolution. Dispersed spores develop into underground gametophytes that survive with the help of symbiotic fungi. This evolution points to interaction with other organisms, which is necessary for survival. Lycophyta can be homosporous [producing one type of spore] or heterosprous, which is more advanced. It produces megaspores [female gametophyes], and microspores [male gametophytes].

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