exchemist
Valued Senior Member
If you tried to fill in my "time/action" table I think you see why (I. e. you can't do it without internal conflict, I think.) but I'll try a different approach:
here is diagram of simple two-way breather inhaling:
At t = 0 : ---> O and then at t = 2- inhale nearly completed (lungs "O" is larger, lungs have expanded) --->O
Now at t= 2+: <--- O and at t = 4- exhale is nearly completed <---- O
You want to postulate this creature gets second air flow bath (two different paths for air flow between outside and lungs) but why would separate paths evolve in a two way breather? That is what I call an impossible "binary change." If the creature needed channel with greater air flow the existing single nose and tube to the lungs could INCREMENTALLY enlarge over the course of many generations - Evolution CAN do that.
I'll use bold to indicate an enlarged airway.
At t = 0 : ---> O and at t = 2- ---> Oetc. for the exhales
Note the 2- is time almost 2 & the 2+ is times just a little more than 2
At t =2+ <--- O Etc for t = 4- I.e. like second line but with arrow bold
I.e. we now still have a 2-way breather but with greater air flow.
If you cold make a binary change to increase the air flow
It might be drawn as:
Path A : ---> ....
Path B: ---> ....
I don't want to tell you how the 1-way final creature looks, even assuming getting new path were not a binary change, but let you use colors (first one bold to indicate it has 75% of the inhale flow and then the other bold for 75% of the exhaling flow. In all cases and at all times your one way flow must have the arrow path thur the lungs going the same way:
----> O ----> then:
----> O ---->
The above, I think, is what you are telling me works, but I'm not sure and don't see how it would even if you could justify the entirely new flow path (A binary change) It would not have any advantage in the first born with it. Why would it be selected for?
BTW now I see another great problem with the new sciforums. When you have made something bold or with color wrong and edit to change it the [b ] or [color= ] commads do not show, but take effect.
For example I am now editing as don't want this or "commnds.... to be bold aand don't want any of these last two paragraphs to be in color, but as this is an edit the commands making that don't show for me to remove!
Ah, I see, so now you are claiming that the appearance of a second air connection to the lung is a "binary change" and thus impossible. I disagree. Without knowing the layout of the bronchi and lungs in these early creatures, it seems to me illogical to say it is impossible, any more than a hole in the heart is "impossible" - when in fact it is very common.
As for the asymmetric tidal flow which I am suggesting as a half way house, it is clear you still either can't understand it or else are determined to make artificial difficulties for some reason. I do not have the patience to spend more time on this with you.
As I say, I'm grateful to Trippy and others for an enlightening discussion.