Water lilies
The earliest flowering plants are thought to have been weedy shrubs that lived alongside streams. One of these early groups to evolve was the water lily family.

Magnolias
Magnolias (Magnoliales) were among the first groups of flowering plants to evolve. Fossils of Magnolia-like plants are known from early-mid Cretaceous sediments (Aptian-Albian, ~112 Ma) in North America. Because Magnolia, and many other early flowers have large bisexual flowers with very many floral parts (carpels, stamens) compared to later (more “derived”) groups of flowering plants, it was long thought that this represented the “primitive”(ancestral) condition from which other flower types evolved. Now we know that both very large flowers with numerous parts (such as Magnolia,) and simple flowers with few floral parts, existed among the earliest flowers.

Magnolia

Paleontologists have suggested a few explanations for why flowering plants evolved at the end of the dinosaur era (~140 Ma):

• The environment during the Cretaceous – which was warm and dry – favored the evolution of flowering plants
• Flowering evolved in conjunction with plant-eating dinosaurs
• Flowering plants evolved in conjunction with insects
  It is also possible that flowering plants DID evolve earlier than the late Mesozoic, but the plants were so small and fragile they didn’t fossilize.

Unfortunately, none of these hypotheses are well supported.

Click here for a species list and images of living plants
with Mesozoic ancestors.