Michael Denton and the Question of the Origin of Birds

Of course evolution is a scientific fact, and the origin of birds by progressive sequential development of scientific facts that should not be discussed by anyone scientist! But Michael Denton is a scientist, he has a PhD in developmental biology and has worked as a biology researcher for dozens of years, and he dared to ask: how can the lungs of birds be created? Denton sees no sequential (step-by-step) path to bird lung development that will not be functional in its intermediate stages, and therefore natural selection will not preserve the survival of organisms in which the first stage of this path may have originated, simply because it will not be functional, and nonfunctionality is a dead end to evolution!! In other vertebrates, air is drawn into the lungs through a system of branching tubes that end with very small air sacs or air horns thus moving the air as you breathe in and out of the same passageway. But in the case of birds, the major bronchi branch into tiny tubes that penetrate into the lung tissue. These tiny tubes called the peripheral bronchi eventually clump together again, forming a real cyclical system, so that air moves in one direction in the lung. Keeps air flowing in one direction while inhaling and exhaling through a complex system of connected and interconnected alveoli in the bird’s body, these alveoli contract and expand in a way that ensures continuous supply of air through the bronchi network. The presence of this vesicle system in turn necessitated a unique and highly specialized division of the bird's body cavity into several compressible compartments. Although alveoli are found in some groups of reptiles, the lung structure in birds and the overall way in which the respiratory system works are both very distinct, there is no known lung in any vertebrate species resembling the respiratory system of birds, and this device is also identical in all major details in various birds, from hummingbirds to ostrich and falcons. How could such a completely different respiratory system evolve gradually from the normal design of vertebrates? It is very difficult to imagine, especially if one remembers that maintaining respiratory function is absolutely necessary for the life of the organism, so much so that the simplest defect leads to death in just a few minutes. Just as a feather cannot function as an organ to fly until the hooks and spines are also perfectly adapted to each other, so a bird's lung cannot function as a respiratory organ until each organ develops. The distinctive function and shape of the bird’s lung also requires a number of unique adaptations during the bird’s development. As Dunker19, one of the world’s leading scientists in the field, explains, the bird’s lung is firmly attached to the body wall and cannot expand in size. Second, because of the small diameter of the lung capillaries and the resulting large surface tension of any fluid in the capillaries, the two causes of infection cannot be felt. The final development of the lung, and specifically the growth of the capillary network, begins only after the main air channels are already filled with air, and the capillaries do not contract at all as occurs in the alveoli of other vertebrate species, but as the capillaries grow to form lung tissue, the oceanic bronchi open from the beginning air-filled tubes or a fluid that then absorbs into the capillaries. Gentlemen, scientists who have tons of evidence for the correctness of evolution are bringing it out in Denton's face, to expose his profound ignorance of the greatness of Darwinian evolution! 17. Stahl, B.J. (1974) Vertebrate History: Problems in Evolution, McGraw-Hill Book Co, New York, p349. 19. Duncker, H. R. (1978) "Development of the Avian Respiratory and Circulation Systems", in Respiratory Function of Birds, Adult and Embryonic, ed J. Piiper, Springer Verlag, New York, pp260-73, see Figure on p269. More about Denton's book: https://braheen.com/publications/التطور-نظرية-في-أزمة — Source: Published on Facebook's "Braheen Center" page https://www.facebook.com/braheen.org/posts/pfbid02kYS7aRXPK8UcuSNHpiJWqFoLJ8M2n6ZQP8V679QqaSysB6QoXt3jW2QbEM13vdzMl