Life Cycle/Reproduction

Reproduction is a major part in all organisms life cycle. Organisms go through one of three life cycles, either zygotic, gametic,  or alternation of generations. As a member of the Angiosperms, Madia gracilis has an alternation of generations life cycle. Characteristics of an alternation of generations life cycle are that the cycle contains two multicellular generations, one of a  gametophyte and one of a sporophyte (Campbell et al 2008).

Every year Madia gracilis plants go through a cycle that makes it considered an annual herb (Ross 2012).  Characteristics of M. gracilis and other annual herbs are that the plant completes a life cycle from seed to plant and then back to seed all in one growth season, with all parts of the plant dying except for the seed (Campbell et al 2008). The germination of M. gracilis occurs when temperatures are much cooler, typically mid to late fall, this late germination is a characteristic found in the winter annuals (Ross 2012, Oregon St. University 2008). Throughout the spring and summer M.gracilis produces seeds for dispersal. The seeds that are produced by the plant fall periodically from the plant throughout the growing season, from there the plant relies on birds, small mammals, and environmental factors to spread the seeds throughout the area (Ross 2012).

The composition of the flower head of M. gracilis is one that helps this species with attracting pollinators. Madia gracilis flower heads are composed of ray florets and disc florets (Celedon-Neghme et al 2007). The ray florets are the brightly colored flower petals that are yellow on the Madia gracilis. These florets help attract pollinators to the plant (Celedon-Neghme et al 2007). In environments where the pollinator’s presence is high the fitness of M. gracilis is also very high because the benefit of the bright ray florets is worth the cost to maintain them. But in environments with low pollinator presence the fitness of M. gracilis is also low because the cost of having ray florets does not result in a high benefit (Celedon-Neghme et al 2007).

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