The Science of Existence (125-5-1) Bladderwort


Some evolved species have no truck with noncoding DNA. The carnivorous bladderwort plant is one.

An unusual and highly specialized plant, the bladderwort lives in fresh water and wet soil, and is endemic to every continent except Antarctica.

The bladderwort’s vegetative organs are not clearly distinguished into roots, stems, and leaves, as in most other angiosperms (flowering plants). But its bladder trap is one of the most sophisticated structures in the plant kingdom.

While many later-evolved species are biased toward archiving noncoding DNA, the bladderwort keeps its genome trim. The bladderwort has 28,500 coding genes: comparable to its relatives, the grape and the tomato. Whereas a grape has 590 million DNA base pairs, and a tomato has 780 million, one bladderwort species (Utricularia gibba) carries only 80 million. This is especially surprising considering that the bladderwort underwent 3 complete genome doublings since it split from the tomato lineage.