Final answer:
True, by age 4, the tongue and larynx have descended anteriorly and are anatomically separated from each other, an adaptation that facilitates complex verbal communication and a wide range of sounds.
Step-by-step explanation:
The statement that by age 4, the tongue and larynx descend anteriorly and the base of the tongue is anatomically separated from the larynx is true. The descent of the larynx and the position of the tongue enable humans to produce a wide range of sounds. This anatomical configuration is very unusual compared to other primates and is part of what allows for complex verbal communication. The larynx extends from the laryngopharynx and the hyoid bone to the trachea, with the epiglottis playing a crucial role in swallowing by covering the trachea, ensuring food is directed towards the esophagus and not into the respiratory tract. Furthermore, the descended larynx, found in humans, plays a role in our ability to speak and is indicative of the vocal abilities shared with Neanderthals, which emerged around 500,000 years ago according to the fossil record.