Final answer:
The first pharyngeal arch gives rise to the lower jaw (mandible) and muscles of mastication (chewing muscles) in humans, as well as the middle ear bones (malleus and incus) in mammals.
Step-by-step explanation:
The first pharyngeal arch, also known as the mandibular arch, gives rise to several structures in the head and neck of vertebrates. In humans, it gives rise to the lower jaw, called the mandible, as well as the muscles of mastication (chewing muscles) such as the masseter and temporalis muscles.
Additionally, the first pharyngeal arch contributes to the development of the middle ear bones (malleus and incus) in mammals. These structures are derived from the initial cartilaginous arches formed during embryonic development.
Overall, the first pharyngeal arch plays a crucial role in the formation of various anatomical structures involved in feeding, jaw movement, and hearing.