![]() ![]() These specimens show the earliest occurrence of wings in this group of dinosaurs leading to birds.” 14 Therefore, Zelenitsky says, “What these specimens do is they fill a significant gap in the record of fossil feathers in the dinosaurs that are linked to birds. Genuine feathers on a Cretaceous ornithomimid would suggest that feathers (and wings to hold them) evolved earlier than previously thought. Maniraptorans are very loosely defined as birds and “all dinosaurs closer to birds than to ornithomimids.” 12 They are the “theropod dinosaurs that many paleontologists believe birds were derived from some 150 or so million years ago.” 13 Ornithomimids are believed to have branched off of the dinosaur family tree just before maniraptorans. Also note that the groupings include actual birds, some being extinct. Note that the ornithomimids are noted to have all three, even though the fossilized evidence only consists of some marks on bony surfaces without any actual feathers or wings being present. The current paleontological findings associated with each group-filaments, feathers, and wings-are indicated. Evolutionists generally believe that maniraptorans evolved into birds. The yellow dot-placed after ornithomimids are said to have branched off-represents the beginning of maniraptorans. The green dot is the proposed branch point for theropods. This phylogenetic tree represents the evolutionary view of dinosaur-to-bird evolution. What selective advantage could feathers have provided? “The fact that wing-like forelimbs developed in more mature individuals suggests they were used only later in life,” Therrien says, “perhaps associated with reproductive behaviors like display or egg brooding.” 9 So if ornithomimids really had feathers, researchers want to know what they used them for. The juvenile, with only filaments, could not have flown from predators. The two ostrich-sized adults, about 12 feet long, are thought to have been too big to fly. Ornithomimus means “bird mimic.” 8 “They superficially resembled ostriches, with a toothless beak, large eyes, long legs, long tail, and now we know they had feathers,” Zelenitsky says, “but these animals were not closely related to ostriches.” The turkey-sized juvenile was about 5 feet long. “This dinosaur was covered in down-like feathers throughout life,” Zelenitsky explained, “ but only older individuals developed larger feathers on the arms, forming wing-like structures.” 6 Illustrations by Julius Csotonyi, published in D. ![]() “A” represents the juvenile, and “B,” the flightless adult with long feathered wings. This artist’s reconstruction was published in Science (“figure 4A/B”) to illustrate the researchers’ interpretation of their findings. “But, based on the size of the markings, we think the ‘wing feathers’ would have been much longer than the filamentous feathers.” 4 “We don't know how long the shafted feathers were on the adult ‘wings,’” Therrien said. 3 The team reports their distribution was consistent with what they would expect if the insertions of feathers on a bird’s bones fossilized. The little marks, 1.5 mm (less than 6/100 of an inch) wide, measured up to 6.5 mm (about ¼ inch) long. In addition to “filamentous feathers”-0.5 mm (less than 2/100 of an inch) wide and 15-50 mm (about ½ to 2 inches) long-the team found, not feathers, but “linear markings on the surfaces of the ulna and radius” 2 of one adult’s forelimb. But what did Darla Zelenitsky, François Therrien, and their colleagues really find? Hailed as the first feathered dinosaurs outside China and Germany, adult ornithomimids are said to have sported long feathered wings. Finally the idea took flight, leading to a full-fledged publication in Science. “It became the running joke.” 1 The three ostrich-like ornithomimids had been found in Upper Cretaceous deposits of Alberta, Canada. “If we were in China, we’d call these feathers,” said curator François Therrien, as he examined some Canadian dinosaurs from Alberta’s Royal Tyrrell Museum of Paleontology. LiveScience: “ Dinosaurs Looking for Love Grew Alluring Feathers”. ![]()
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