The ocean still hides many secrets, and sometimes the smallest or simplest creatures reveal the biggest clues about life. Scientists have long believed that complex animals like humans evolved through a gradual process that shaped our bodies over hundreds of millions of years. However, the exact moment when the model for building a human-like body first appeared remains a mystery. The study suggests that part of that model could already exist in a creature that looks nothing like us, the sea anemone. These soft marine animals live attached to the rocks on the seabed and even lack a brain. Despite that simplicity, researchers say they appear to use a similar developmental mechanism to what humans use during early growth. If the finding is confirmed, it could push the origins of our body plan much deeper into evolutionary history than previously thought.

What scientists discovered about early animal evolution

Sea anemones don’t exactly look like distant relatives of humans.As reported by ScienceDaily research, titled, ‘They find a body plan 600 million years old in sea anemones‘, belong to a group of animals called cnidarians, which includes jellyfish and corals. These creatures usually have bodies arranged around a central point. Imagine a circular structure with tentacles extending outward. Humans are very different. We belong to a large group of animals known as bilaterals. These animals have clear left and right sides, along with a front and back. Our two arms, two legs and two eyes reflect that pattern.For years, biologists treated these two groups as very separate branches of the animal kingdom. Scientists at the University of Vienna recently found evidence suggesting that sea anemones use a developmental trick that closely resembles that used by bilateral animals.

The molecular signals that guide the development of the body.

Building a body inside an embryo is not random. Cells need instructions to tell them where they are and what they should become. This is where molecules known as bone morphogenetic proteins, or BMPs, come into play.BMPs act as small messengers. They send signals that guide developing cells and help determine what type of tissue those cells should form. The skin, organs and parts of the nervous system depend on these instructions.In simple terms, the intensity of BMP signals changes throughout the developing body. Lower levels can help form the central nervous system. Moderate levels may contribute to organs such as the kidneys. Higher levels influence the formation of external tissues.

Scientists discover Chordin’s role in body structure

The Vienna research team focused on another molecule called Chordin. Chordin acts as a kind of regulator of BMP signals. You can lock them in certain areas while transporting them to others. Scientists sometimes describe this movement as “BMP displacement.” This transfer process helps create the gradient that shapes the body during development. Interestingly, the mechanism appears in animals that are not closely related. Frogs use it. Flies do it too. The fish, oddly enough, don’t seem to depend on it in the same way.Because it appears in very distant species, some scientists suspect that BMP transport may be extremely ancient. What is surprising is that sea anemones seem to use a similar system. The researchers observed that Chordin in sea anemones can move BMP signals in a way that helps shape the axis of their body. That discovery suggests that the mechanism could predate the evolutionary split between cnidarians and bilaterians.