Continuing our classic ID the Future series on the long-necked giraffe, that evolutionary icon, we confront a sort of sub-icon, a commonly cited support to arguments for dysteleology, or “poor design.” It’s the recurrent laryngeal nerve.
As Wikipedia explains:
The extreme detour of the recurrent laryngeal nerves, about 4.6 metres (15 ft) in the case of giraffes,:74–75 is cited as evidence of evolution, as opposed to Intelligent Design. The nerve’s route would have been direct in the fish-like ancestors of modern tetrapods, traveling from the brain, past the heart, to the gills (as it does in modern fish). Over the course of evolution, as the neck extended and the heart became lower in the body, the laryngeal nerve was caught on the wrong side of the heart. Natural selection gradually lengthened the nerve by tiny increments to accommodate, resulting in the circuitous route now observed.:360–362
Darwinists including Richard Dawkins and Jerry Coyne have called it one of “nature’s worst designs,” “obviously a ridiculous detour,” asserting that “no engineer would ever make a mistake like that.” Geneticist Wolf-Ekkehard Lönnig returns for a discussion on this point, emphasizing that it’s not a “ridiculous detour” or a “mistake” at all. Download the podcast or listen to it here.
Dr. Lönnig is the author of The Evolution of the Long-Necked Giraffe. See also, “Giraffe Weekend: ‘You Cannot Simply Stretch out the Neck.’”