Scientists have found genetic evidence that could explain why sea dragons are so special, not only that their genomes are full of repetitive pieces of DNA, but they also lack the genes that cause teeth. and nerves in animals.
The discovery of the sea dragon genomes “raises the veil on the evolution of sea dragon characteristics” and “reveals interesting evolutionary aspects of the unusual vertebrate family Syngnathidae as a whole,” the team behind the study said. learners write a new paper.
Sea dragons belong to both the pipefish and seahorse families Syngnathidae, which are famous for developing male pregnancies.
“This group is attractive for many different reasons,” said evolutionary genomics researcher Clayton Small at the University of Oregon, who led the research with Susan Basham: fish.
To find out why, Small, Basham and their team sequenced the genomes of two species of sea dragon, the leafy sea dragon and the sea dragon, or common sea dragon, found in cold waters on the southern coast of Australia.
These slender fish can be hard to see, drifting on their leaf -like foliage that help disguise themselves on rocky, moss -covered reefs.
Scientists believe that sea dragons have developed their traits very rapidly over the past 50 million years as they branched off from seahorses to form a new family.
University of Oregon researchers collaborated with scientists from the Birch Aquarium and Tennessee Aquarium at the Scripps Institution of Oceanography to study samples from sea dragons.
Compared to their closest relatives, tube fish and seahorses, sea dragons have a surprisingly large number of repeating DNA sequences called transposons, known as “jumping genes,” in their genetics. code.
So transposons roam the genome where they can make rapid genetic changes – which may explain why sea dragons change so quickly.
Compared to two distant relatives, the zebrafish and the barb, the genomes of leafy sea dragons and herbivores are missing some of the genes that play important roles in other vertebrates, and contain instructions on how to develop of the structures of the face, teeth, and feet. and even parts of the central nervous system.
While researchers tend to think that the loss of these genes may explain how sea dragons develop long facial features and beautiful frills, more research is needed to delve into the history of evolution of sea dragons and their relatives.
Regardless of the evolution of sea dragons, the results are impressive and fascinating for all we know, and sea dragons may have other secrets hidden in their genomes far, far away, that may reveal further genetic comparison.
The study was published in PNAS.
Source: Science Alert
Source: Arabic RT
