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The author's characterization of this assertion is grossly wrong. He shows a lack of understanding of how a reptile's lungs operate as compared to a bird's lungs (and this comparison is a central thesis of his article).

Furthermore, he engages in the favorite creationist tactic of "quote-mining" and "expert shopping".

"Quote-mining" is hunting for quotes, usually out of context, in order to "prove" something by the simple tactic of "if I can find someone saying it, it must be true". Or even if the creationist can find a quote that *sounds* like what the creationist wants to "prove", even if that wasn't the author's original meaning. For countless examples, and an explanation of why "quote flinging" doesn't prove a damned thing, see: Quotations and Misquotations: Why What Antievolutionists Quote is Not Valid Evidence Against Evolution , and also: The Quote Mine Project: Or, Lies, Damned Lies and Quote Mines.

"Expert shopping" is where the creationist finds one alleged authority (even one of very questionable expertise or credentials) who agrees with him, or sounds like he does, and cites him as "the expert" in the field, whose conclusions ought not be questioned, while at the same time totally discounting the work of all other authorities (no matter how numerous, how expert, or even if they are the acknowledged top authorities in their field) as being "obviously" mistaken because they differ with the "unquestionable" conclusions of the creationist's handpicked "authority". The dishonesty of this technique should be obvious to all -- it's a variation on "I'll believe whatever I want to believe, and ignore the rest".

An example of the latter is the author's reliance upon Ruben, who made an offhand remark in a paper about another subject, and to the creationist author that makes him "the" authority on the topic of theropod/avian respiration, despite Ruben's conclusions being disputed by many other researchers.

A look at Ruben's full paper, in contrast with the creationist's quote from it, shows that Ruben's paper did not primarily concern when the avian-style lungs might have developed (or how), it covered when *endothermy* might have arisen. The remark on the rise of the avian-style lung was an offhand comment near the end of the paper, and rather an odd inclusion at that. The creationist took it to mean that Ruben was arguing that birds could not have arisen from theropod dinosaurs due to alleged incompatibilities in their respiratory systems, BUT in the context of the rest of Ruben's paper, the same argument could have been applied to claim that modern birds couldn't have arisen from early *birds* either, since Ruben had concluded that both groups (theropod dinosaurs *and* early birds) had diaphram-driven lungs. So the comment doesn't make much sense unless Ruben also wishes to argue that modern birds are unrelated to more primitive birds! And from the rest of his paper, it is quite clear that he does *not* believe that -- Ruben believes in evolution and common descent.

So the creationist was taking an offhand and apparently rather garbled comment, out of its context, and waving it around as "proof" of the conclusion he was trying to make, while *ignoring* all research results to the contrary. Not very honest, eh?

In any case, Ruben's comment appears to be mistaken, because it falsely presumes (and fails to even attempt to establish) that a diaphram can't co-exist with an avian-style respiratory system. It also incorrectly assumes that air flow to air sacs would have to take place *through* the diaphram, and yet it's well-known that air flow in birds includes vertebral diverticula -- in layman's terms, air tubes extend into and through the spinal column. It's entirely possible that airflow between abdominal air sacs and the thoracic lungs took place through the spine in birds' ancestors which still had a diaphram, thereby *bypassing* the diaphram instead of having to pass *through* it.

In any case, Ruben's conclusion that early birds and theropod dinosaurs did not have avian-style "pass through" respiration has been superseded by subsequent findings (which the creationist webpage has "forgotten" to update accordingly):

Basic avian pulmonary design and flow-through ventilation in non-avian theropod dinosaurs (2005)
Abstract: Birds are unique among living vertebrates in possessing pneumaticity of the postcranial skeleton, with invasion of bone by the pulmonary air-sac system. The avian respiratory system includes high-compliance air sacs that ventilate a dorsally fixed, non-expanding parabronchial lung. Caudally positioned abdominal and thoracic air sacs are critical components of the avian aspiration pump, facilitating flow-through ventilation of the lung and near-constant airflow during both inspiration and expiration, highlighting a design optimized for efficient gas exchange. Postcranial skeletal pneumaticity has also been reported in numerous extinct archosaurs including non-avian theropod dinosaurs and Archaeopteryx. However, the relationship between osseous pneumaticity and the evolution of the avian respiratory apparatus has long remained ambiguous. Here we report, on the basis of a comparative analysis of region-specific pneumaticity with extant birds, evidence for cervical and abdominal air-sac systems in non-avian theropods, along with thoracic skeletal prerequisites of an avian-style aspiration pump. The early acquisition of this system among theropods is demonstrated by examination of an exceptional new specimen of Majungatholus atopus, documenting these features in a taxon only distantly related to birds. Taken together, these specializations imply the existence of the basic avian pulmonary Bauplan in basal neotheropods, indicating that flow-through ventilation of the lung is not restricted to birds but is probably a general theropod characteristic.
Vertebral pneumaticity, air sacs, and the physiology of sauropod dinosaurs (2003)
Abstract: The vertebrae of sauropod dinosaurs are characterized by complex architecture involving laminae, fossae, and internal chambers of various shapes and sizes. These structures are interpreted as osteological correlates of a system of air sacs and pneumatic diverticula similar to that of birds. In extant birds, diverticula of the cervical air sacs pneumatize the cervical and anterior thoracic vertebrae. Diverticula of the abdominal air sacs pneumatize the posterior thoracic vertebrae and synsacrum later in ontogeny. This ontogenetic sequence in birds parallels the evolution of vertebral pneumaticity in sauropods. In basal sauropods, only the presacral vertebrae were pneumatized, presumably by diverticula of cervical air sacs similar to those of birds. The sacrum was also pneumatized in most neosauropods, and pneumatization of the proximal caudal vertebrae was achieved independently in Diplodocidae and Titanosauria. Pneumatization of the sacral and caudal vertebrae in neosauropods may indicate the presence of abdominal air sacs. Air sacs and skeletal pneumaticity probably facilitated the evolution of extremely long necks in some sauropod lineages by overcoming respiratory dead space and reducing mass. In addition, pulmonary air sacs may have conveyed to sauropods some of the respiratory and thermoregulatory advantages enjoyed by birds, a possibility that is consistent with the observed rapid growth rates of sauropods.