The Avian Lung
A recent comment on this blog, challenged me thus:
If evolution is true then how did the avian lung develop.
That’s right I went there. While you atheists can place your store in purposeless fallacies I choose to hope because hope is all that is left of our ignorant race. And maybe one day as I did, instead of closing your eyes maybe you will open them and see your lies, or even accept the truth as I did, instead of trying to bury it!
—thus spoke mattmitch.
feel free to send a rebuttal
Well, mattmitch, I’d firstly like thank you for bringing this to my attention. I was certainly not aware that the entire field of evolution, and the philosophical position of atheism, were both under threat by the structure of the humble avian lung. Frankly, beyond the knowledge that the avian lung was significantly superior to our mammalian lung, I hadn’t really done much reading on the subject. So I can certainly say that thanks to your comment, I am now more educated on the subjects of how bird lungs work, and baseless arguments made by creationists.
As to a rebuttal, there are a couple of ways we could go with this. Let’s start with the obvious one:
I assume that since your comment is both anti-evolution and anti-atheist, you are yourself a creationist. This implies that your opposing position is that God made the avian lung in all its glory. Assuming this is true, please explain why he chose to short-change his favourite creation, humans, in the lung department? Since the avian lung is considerably superior to ours, is God trying to tell us something by giving us shoddy lungs? Were we, perhaps, too busy standing in the brain line when the good lungs were handed out? I challenge you, in fact, to explain this obvious disparity in any way other than appealing to God moving in mysterious ways.
But as satisfying as that response may be, we don’t really learn anything from it. So here’s the other option, the one that requires some research (that’s when you go look stuff up instead of just making it up for yourself, you might like to try it):
Recent evidence suggests that oxygen levels were suppressed worldwide 175 million to 275 million years ago and fell to precipitously low levels compared with today’s atmosphere, low enough to make breathing the air at sea level feel like respiration at high altitude.
Now, a University of Washington paleontologist theorizes that low oxygen and repeated short but substantial temperature increases because of greenhouse warming sparked two major mass-extinction events, one of which eradicated 90 percent of all species on Earth.
In addition, Peter Ward, a UW professor of biology and Earth and space sciences, believes the conditions spurred the development of an unusual breathing system in some dinosaurs, a group called Saurischian dinosaurs that includes the gigantic brontosaurus. Rather than having a diaphragm to force air in and out of lungs, the Saurischians had lungs attached to a series of thin-walled air sacs that appear to have functioned something like bellows to move air through the body.
“The reason the birds developed these systems is that they arose from dinosaurs halfway through the Jurassic Period. They are how the dinosaurs survived,” he said.
So actually, the ‘avian’ lung came before birds, and evolved in dinosaurs because of selection pressures for survival in low oxygen environments that killed off most of their competitors. It’s the resulting enormous network of airsacs, which extend even to within their bones, that allows their avian ancestors to be so much lighter, and therefore to fly. Without the ‘bird’ lung, we probably wouldn’t have birds in the first place. Which I hadn’t known. So again, mattmitch, thanks to your bizarre, almost Tourettesian outburst, I actually did open my eyes and discover some new truth today. I hope you did likewise.