What a fun time everyone appears to have had in this thread.
I have read as extensively as my admittedly modest level of education has allowed me to on the issue of biogenesis and the early Earth. People on both sides of the debate are guilty of haphazardly applying faith in the absence of testable data to the question “how likely is the series of supposed processes which trasnforms pre-biotic molecules into operating cells taken against the organizational minimum and the time available”.
Someone like Michael Behe and someone like Richard Dawkins are both arguing from a lack of information on this question. Behe is good at articulating the necessary level of complexity that accompanies life processes on the cellular level, and Dawkins is good at proposing ideas for non-biotic processes that might introduce structural order onto disorganized pre-biotic chemicals. However, this is, without probabilities indexed to time, not very useful. I am not a microbiologist, I can make no more headway in examining the merits of the arguments.
So, I don’t dwell on that.
I design things for a living, machines, and they happen to fly. So, I have an interest, and experience, in mechanical flight. This I can dig into. We do know how a bumblebee flies - or at least we’ve made some more strides in the field of turbulent lift since the famous “the bumblebee shouldn’t fly” headlines. What we know is that flight is very, very complex. There are two basic components to flight - structure and behavior. In each there are many subcomponents.
For a flying thing to work, both components must function. First, the structure: The wing surfaces must be matched in size to the force of the muscles attached to them and the weight of the payload. The cycle speed of the power system must be correct within a range to develop lift and control with a given wing size and shape. Insertion points of adequate strength must be provided for the muscles. Pivot points of adequate travel must be provide for the wings to articulate. The biochemistry of the muscles must the matched to the duration of the powered portion of the flight profile. For many flight systems (see the bee) the stiffness of the wing surface must be within a narrow range to allow the lifting surface to passively change shape during the stroke. The remaining support systems (fuel storage, guidance and nav, landing gear) have a maximum weight value which requires specific structures, or else the load is too great for the flight system to lift.
Then, the behaviors: On some systems, the angle of attack of the lifting surface must be varied actively during the stroke, and error in the angle or attack is not allowed outside a range of only a few degrees. Wings do not “flap”, they describe a complex curve and this travel path must be observed without significant variation. On all systems, the differential lift vectors supplied by two or more lifting surfaces must be managed to supply climbing, turning, banking and other desired maneuvers. On some systems, an articulated tail surface is added and the angle of attack of this aurface must be actively maintained in three dimensions. Recovery behaviors to manage wind gusts and upsets must exist. Takeoff and landing routines are required.
On these systems, large errors cannot be tolerated. Make a change to a flight surface, the system does not function. Make a small change to the musculature of the flying animal, it cannot fly. Take away part of the “flapping” stroke. No flight. Remove only one axis of control on the surfaces, no flight.
Flying animals are very precise solutions to particular engineering problems. This type of solution is called a “mountain top” solution because all of the adjacent data sets do not provide other comparable solutions, but instead are very deficient. Each solution, or particular set of values, exists like a steep mountain on the graph of possible solutions. You cannot iterate to a mountaintop solution.
Every aspect of biology, to hear the experts talk about their own fields, has mountaintop solutions like these. It’s impossible to iterate to these solutions, because any deficiencies (like the ones envisioned by ANY evolutionary scheme in a trasitional form) render the system not just sub-optimal, but profoundly non-functioning.
Anytime complex, complementary structures exist in life-forms, they potentially represent mountaintops. In the case of multiple, complementary, complex structures with necessary, instinctive, highly complex associated behaviors, iteration is not possible and the question of time is rendered moot. Impossible events remain impossible over any time span.
Now, I realize that, as a Catholic, I am allowed to “believe in evolution” with wide latitude, and at one time I did. However, I no longer think mutation+selection represents real possible explanations for organisms. I don’t see any reason why this means the only other possible explanations are supernatural, and if the Church was allowing us to accept Darwinism when it was the best candidate, I don’t see why the Church would seek to prevent us from accepting whatever the next approximation is. But, and I see no alternative to this, there will be a next approximation, and it will have to address the actual level of complentary complexity of structure and behavior in real organisms.