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| Fluorescent probes used to highly the chromosomes of birds also worked to illuminate the chromosomes of turtles, allowing scientists to compare the genomes of the two groups and estimate the genomic structure of its last common ancestor, a reptile species living 260 million years ago. Photo by Nicole Valenzuela/University of Kent |
By Brooks Hays, UPI
Scientists can begin to imagine what a dinosaur's genome would look like under a microscope thanks to turtles and birds.
By comparing the genomes of turtle and bird species, distant relatives of dinosaurs, researchers were able to approximate the genomic structures of the ancient reptiles, including those of famed species like the velociraptor and tyrannosaurus.
Before scientists could recreate the genomic structures of dinosaurs, they traced the genetic lineage of birds and turtles to a common ancestor living 260 million years ago, 20 million years before the first dinosaurs showed up. This provided researchers with a starting point.
Next, scientists had to determine how the shape of a reptile's genome evolves over time.
By comparing the archetypal genome of the distant reptilian ancestor to the genomes of modern and birds and turtles, researchers at the University of Kent were able to estimate the chromosomal changes across evolutionary time.
Their research -- published Monday in the journal Nature Communications -- showed chromosomes regularly rearranged their internal genes, but that the relationships between chromosomes remained fairly stable over time.
Birds have a lot of chromosomes, and researchers believe dinosaurs did too. The trait could explain why dinosaurs -- like birds are today -- were incredibly diverse. If researchers were to recreate the chromosomes of a theropod dinosaur, scientists estimate it would look much like the genome of an ostrich, duck or chicken.
"This genomic structure therefore appears highly stable yet contributes to a large degree of phenotypic diversity, as well as underpinning adaptive responses to major environmental disruptions via intrachromosomal re-patterning," researchers wrote in their newly published paper.
Scientists were able to probe the makeup of turtle genomes using fluorescent probes designed to illuminate chromosomes in birds.
