You are expecting complex systems to evolve as a unit, it doesn't happen that way as per my understanding. The gene is the evolutionary unit. The ear didn't evolve to be an ear, the genes that code the structure and function of the ear are what evolved. All genes want nothing more than to replicate themselves, whether it is for the benefit or detriment of the host is irrelevant to the gene. Luckily, having an ear lessens natural selection pressure.

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90 300TE 4-M
Turbo 103, T3/T04E 50 trim
T04B cover .60 AR
Stage 3 turbine .63 AR
A2W I/C, 40 LB/HR
MS2E, 60-2 Direct Coil Control
3" Exh, AEM W/B O2
Underdrive Alt. and P/S Pulleys,
Vented Rear Discs, .034 Booster.
3.07 diffs 1st Gear Start

90 300CE 104.980
Milled & ported head, 10.3:1 compression
197° intake cam w/20° advancer
Tuned CIS ECU
4° ignition advance
PCS TCM2000, built 722.6
600W networked suction fan
Sportline sway bars
V8 rear subframe, Quaife ATB 3.06 diff