Evolution of a plant

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The unique angiosperm flower probably evolved from a now extinct gymnosperm group that had insect-pollinated cones combining male and female reproductive parts. Living gymnosperms are mostly wind-pollinated, but among certain fossil and extant groups evidence of insect pollination exists. Although insects facilitate pollination, they also eat ovules, and it is believed that the development of the ovule-enclosing carpel of the angiosperm was an adaptation to protect the ovules and developing seeds from insect predation. The carpel also provided protection from other harmful environmental influences, such as dryness, and it allowed reduction in the size of the ovule, refinement of the process of pollination, and the development of other parts of the flower, all of which improved the chances of successful reproduction.


See also:
angiosperms; parts of a flower; Gymnosperm and Angiosperm Seeds; dicot; monocot

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