Final answer:
The Los Angeles cover band of New Wave of British Heavy Metal songs is not specified, but the transition from Surf Rock to grunge in the Pacific Northwest and its contrast to Los Angeles-based hair metal scene is detailed, emphasizing grunge's heavier sound, introspective lyrics, and subdued aesthetics.
Step-by-step explanation:
The group that originally started out as a Los Angeles cover band of New Wave of British Heavy Metal songs is not clearly identified in the information provided. However, the history of rock music from the Pacific Northwest, particularly Seattle, demonstrates a shift from the pop-oriented Surf Rock of the 1960s to the emergence of grunge in the 1980s. This movement incubated in isolation before gaining mainstream recognition, differentiating itself significantly both in sound and aesthetics from the Los Angeles-based hair metal scene. Bands in Seattle eschewed themes of girls, cars, and partying for more introspective and politically charged lyrics, turning to a heavier sound through downtuned guitars and a distinct punk-rock aesthetic.
Comparatively, Los Angeles-based bands like Poison embraced the glitz and glam of hair metal, exemplified in hits like "Talk Dirty to Me," and a very different look that included spandex, makeup, and an up-tempo vibe. The sharp contrast between the looks of the bands in both regions, from the flannel and work boots of Seattle's grunge bands to the spandex-and-makeup of Hollywood's hair metal bands, highlights the divergence in the evolution of rock culture in the United States during the late 1980s and early 1990s.