Key Finding: A study published in 2025 in Science Advances reveals that sea anemones (phylum Cnidaria) use bone morphogenetic protein (BMP) shuttling, a technique long associated with bilaterians, to develop their body axes.
Ancient Origins of a Key Developmental Mechanism
A new study has uncovered a surprising link between sea anemones and more complex animals, suggesting a crucial developmental mechanism is far older than previously thought.
Scientists have observed that sea anemones—creatures belonging to the phylum Cnidaria—utilize a molecular process known as bone morphogenetic protein (BMP) shuttling to establish their body axes. This technique was previously believed to be a hallmark of bilaterians, the group of animals with bilateral symmetry that includes everything from flies to frogs, and humans.
In a striking parallel to bilaterians, researchers found that Chordin, an inhibitor that also acts as a BMP shuttle, is present and active in sea anemones.
The presence of this mechanism in both Cnidaria and Bilateria suggests it may have evolved before the two phyla diverged, approximately 600 to 700 million years ago.
The discovery implies that BMP shuttling may be an ancient developmental mechanism, potentially inherited from the last common ancestor of these two major animal groups. This finding reshapes our understanding of the evolutionary timeline of body plan formation.
However, the researchers, led by David Mörsdorf and Grigory Genikhovich at the University of Vienna, note that the possibility of independent evolution of this trait cannot be ruled out entirely.