The embryo initiates germination on the seed, still attached on the tree and further develops into a propagule. This phenomenon is known as vivipary. Mangroves aid soil formation by trapping debris. Prop roots and pneumatophores accumulate sediments in protected sites and form mangrove peats.
Botanists believe that mangroves originated in Southeast Asia, but ocean currents have since dispersed them to India, Africa, Australia, and the Americas.
