A new study published in the October 26 edition of Science, led by paleontologists Darla Zelenitsky from the University of Calgary, describe the first the first dinosaur named Ornithomimus found with evidence of feathers preserved in a juvenile and two adult skeletons in North America that had been discovered in 1995, 2008, and 2009. The published study was entitled “Feathered Non-Avian Dinosaurs from North America Provide Insight into Wing Origins”.
“This is a really exciting discovery as it represents the first feathered dinosaur specimens found in the Western Hemisphere,” says Zelenitsky, assistant professor at the University of Calgary and lead author of the study in a ScienceDaily interview. “Furthermore, despite the many ornithomimid skeletons known, these specimens are also the first to reveal that ornithomimids were covered in feathers, like several other groups of theropod dinosaurs.”
The first Ornithomimus was discovered by Othniel Charles Marsh in 1890 in the Denver Formation located in the state of Colorado. More recently, the Ornithomimus at roughly 11 feet long and 350 pounds, reached stardom in the science fiction Jurassic Park movie portrayed as a herd of scaly, feet-footed animals chased by the ferocious Tyrannosaurus rex running at 30 miles an hour. In the movie, Steven Spielberg did not cast the dinosaur covered with a fluff-ball of feathers because its feathered status was not known at the time.
“This dinosaur was covered in down-like feathers throughout life, but only older individuals developed larger feathers on the arms, forming wing-like structures,” Zelenitsky explained to ScienceDaily. “This pattern differs from that seen in birds, where the wings generally develop very young, soon after hatching.” The forelimb feathers, however, does not indicate flight.
“The fact that wing-like forelimbs developed in more mature individuals suggests they were used only later in life, perhaps associated with reproductive behaviors like display or egg brooding,” says François Therrien, curator at the Royal Tyrrell Museum and co-author of the study.
Rather than feathers for flight, the authors theorize that the feathers originated and evolved for the purpose of mating: “the appearance of winglike structures [only] in older animals indicates that they may have evolved in association with reproductive behaviors.”
Zelenitsky’s theory, however, contradicts previous evolutionary theories. Danish zoologist, Gerhard Heilmann, in The Origin of Birds (1926) proposed that the feather originated “by the friction of the air the outer edges became frayed, the fraying gradually changing into still longer horny processes which in the course of time became more and more feather like.” This theory became known as the ‘from the trees down” or the “arboreal theory”.
In the article Bird Flight, How Did It Begin (1979) published in the American Scientist, Yale palaeontologist John Ostrom undermined the “arboreal theory” by pointing out that “the animal had to be able to climb. However… that may not have been part of the repertoire of primitive birds, or even bird ancestors [presumably dinosaurs].” Climbing trees was obviously not in the Ornithomimus repertoire.
Ostrom flipped the theory of dinosaur feather evolution in the 1960s back to the same theory first proposed by Darwin’s closest advocate Thomas Huxley in the 1860s. Ostrom, like Huxley (nicknamed “Darwin’s bulldog”), advocated the “from the ground up” or “cursorial theory” of feather evolution.
“It is possible”, Ostrom had argued, “that the initial (pre-Archaeopteryx) enlargement of the feathers on its hand might have been to increase the hand surface area, thereby making it more effective in catching insects? Continued selection for larger feather size could have converted the entire forelimb into a large, light-weight ‘insect net.’ It is not difficult to visualize how advantageous these paired ‘insect nets would be in the snaring lapping insects, or even in batting down escaping flying insects.” Dinosaur feathers, then, were theorized to have evolved for the purpose of capturing prey.
Since the feather evidence Zelenitsky’s team discovered was only seen in the adult Ornithomimus, the research team was forced to reject Ostrom’s “cursorial theory” since the young must catch prey, too.
The research team concluded that the origin of feathers was for creating mating attraction: “The appearance of winglike structures in older animals indicates that they may have evolved in association with reproductive behaviors.”
This conclusion was drawn by inference. In an interview with the Smithsonian Institute, Zelenitsky explained that “we infer that because these wing feathers are not showing up until later in life, they were used for reproductive purposes.” The key word in this interview is “infer”. Zelenitsky inferred mating evidence based on deductive reasoning−not inductive reasoning.
Only through the Scientific Method by using inductive reasoning, not through inference or deductive reasoning, can a theory be established as a scientific fact.
Since the now discredited “arboreal” and “cursorial” theories were founded on deductive reasoning, Zelenitsky’s similar deductive conclusions are certainly at high risk for the same fate.
Zelenitsky’s mating theory for the origin of the feather simply fulfills a disparate philosophy void required for establishing biological evolution as a scientific fact. However, scientific facts can never be established by deductive reasoning and inferences. Zelenitsky’s team never established the process of feather evolution based on scientific evidence.
Paleontologists, according to Stephen J Gould, “We fancy ourselves as the only true students of life’s history, yet to preserve our favored account of evolution by natural selection we view our data as so bad that we almost never see the very process we profess to study.”
Evolution was once a theory in crisis, now evolution is in crisis without a comprehensive theory. Zelenitsky’s study highlights the disparate measures that continue to dominate the evolution industry. Evidence for the origin of the feather, while a frustrating evolution enigma, is compatible with the Genesis origin of life account.