Closest animal to dinosaurs
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Closest Animal to Dinosaurs: Insights from Dromaeosaurids
Dromaeosaurids and Their Relation to Birds
Dromaeosaurids, a group of theropod dinosaurs, are among the closest relatives to modern birds. These dinosaurs, often referred to as "feathered dinosaurs," provide significant insights into the evolutionary transition from non-avian dinosaurs to birds. The Early Cretaceous period in Liaoning Province, China, has yielded several important dromaeosaurid fossils that highlight this close relationship.
Feathered Dromaeosaurids: Evidence from Liaoning
The discovery of Zhenyuanlong suni, a large-bodied, short-armed dromaeosaurid from the Early Cretaceous of Liaoning, has provided crucial evidence about feather evolution in these dinosaurs. Unlike its smaller relatives, Zhenyuanlong had large wings with pennaceous feathers on its arms and tail, but it likely lacked vaned feathers on its legs. This finding suggests that even non-volant dromaeosaurids had complex feather structures similar to those of their volant relatives, indicating a diverse range of feather morphologies among these dinosaurs.
Microraptor: Bridging the Size Gap
Another significant discovery from the Early Cretaceous Jiufotang Formation of Liaoning is Microraptor zhaoianus. This small dromaeosaurid is notable for being the first mature non-avian dinosaur found to be smaller than the primitive bird Archaeopteryx. Microraptor's bird-like features, such as its teeth, ischium, and foot morphology, provide valuable insights into the morphological transition from non-avian theropods to birds. The nearly completely articulated foot of Microraptor, with features comparable to those of arboreal birds, suggests that some non-avian theropods had adaptations for an arboreal lifestyle, further blurring the line between these dinosaurs and early birds.
Conclusion
The dromaeosaurids from the Early Cretaceous of Liaoning, China, such as Zhenyuanlong suni and Microraptor zhaoianus, are among the closest relatives to modern birds. Their well-preserved fossils provide critical evidence of the evolutionary transition from non-avian dinosaurs to birds, highlighting the diversity in feather morphology and adaptations that existed among these ancient creatures. These discoveries underscore the intricate evolutionary relationship between dromaeosaurids and birds, offering a clearer picture of how modern birds evolved from their dinosaur ancestors.
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