Sea Anemones Revealed to Hold Ancient ‘Blueprint’ for Animal Bodies
Sea anemones may appear otherworldly, but recent scientific findings have uncovered that they harbor an ancient ‘body blueprint’ that most animals, including humans, still adhere to. This discovery has the potential to revolutionize our understanding of evolution timelines.
While you may not be familiar with the term ‘bilaterian,’ you are indeed one. Bilaterians are creatures with a body plan that exhibits symmetry along a single plane. From worms to whales, ants to elephants, and humans to hummingbirds, this symmetrical structure is prevalent.
On the other hand, radial symmetry characterizes another major animal body plan, where creatures organize their bodies around a central axis. Think of a jellyfish, and you’ll understand the challenge of determining which side is the ‘front’.
Most animals in the cnidaria phylum, which includes invertebrates like jellyfish, sea anemones, and corals, typically display radial symmetry.
However, the sea anemone, despite being a cnidarian, exhibits bilateral symmetry, raising questions about the evolution of this feature and how many times it may have occurred.
To investigate this further, researchers at the University of Vienna in Austria conducted experiments on starlet sea anemones (Nematostella vectensis) to observe their embryonic development.
Bone morphogenetic protein (BMP) plays a crucial role in how bilaterians construct their bodies. Essentially, a BMP gradient instructs developing cells on the tissues they should become based on their location in the body.
In some bilaterians, like frogs and flies, this gradient is established through the action of another protein called chordin, which transports BMP throughout the body.
The study revealed that sea anemones also employ this BMP shuttling mechanism, indicating that this mechanism likely evolved before the divergence of bilaterians and cnidarians over 600 million years ago.
“The fact that sea anemones, not just bilaterians, utilize shuttling to determine their body axes indicates the antiquity of this mechanism,” stated developmental biologist David Mörsdorf, the study’s lead author.
This discovery opens up new avenues for reevaluating how body plans evolved in early animals and was published in the journal Science Advances.
