Original: The similarity of the structures in other respects, despite the complex nature of the organ, illustrates how there are some biological challenges (vision) that have an optimal solution.
Simplified: doi :10.2277 \/O/ 0521827043, ISBN 0-52-160325-0, OCLC 156902715 The similarity of the structures in most respects, despite the complex nature of the organ, illustrates how there may be some biological challenges which have an optimal solution.