What are some of the reasons for variations in flowers types?

Question

What are some of the reasons for variations in flowers types?

Answer 1

mutations or genetic variations that occur during the alternation of generations...

when spores undergo meiosis to produce the haploid spore, meiosis ensures genetic variability

those spores that are formed then deveolp into gametophytes, when then form either the egg or sperm in mature plants.

i hope this helped you out!

Answer 2

Flowers vary because they take advantage of different types of pollinators.  Flowers that get pollinated by wind need to have small petals to allow the anthers and stigmas exposed.  Flowers with large petals that enclose the reproductive organs are likely pollinated by birds, insects, or bats.  Because birds can see bright colors, but don't have a good sense of smell, those flowers will be brightly colored.  Bats fly at night, so their flowers don't need to be brightly colored, but do need to emit odors.  Insects can use both smell and sight and can also see UV, so flowers pollinated by insects will reflect these traits.

Additionally, because different pollinators have different mouth parts and body shapes, the flowers have coevolved to facilitate pollination by different species.  For example, there are some orchids that have flowers that look just like bees and the mimicry is so good that sometimes bees are seen trying to mate with the flowers.  

Also, flowers don't want to be visited by just any pollinator.  To ensure that they are likely getting pollen from their own species, they have evolved flowers that will attract a narrow range of pollinators.  So, some flowers have adapted for hummingbird pollination, some for butterflies, some for bees, etc.  This leads to different shapes, coloration, and odors.