1. Industrial melanism, a prime example of natural selection studied by Kettlewell, involved two UK peppered moth varieties: Biston betularia and Biston carbonaria.
2. In pre-industrial Britain, Biston betularia outnumbered Biston carbonaria. B. Betularia was greyish-white, while B. carbonaria had a melanic form.
3. Nocturnal moths rested on tree trunks during the day. White-winged moths blended with lichen-covered bark, evading predators. Melanic forms were more visible, leading to higher predation.
4. Industrialization and air pollution darkened tree trunks, favoring melanic forms. White-winged moths became conspicuous against changed tree colors, facing increased predation.
5. Natural selection responded to environmental shifts, favoring adaptive traits and impacting population dynamics.
6. The industrial revolution decreased white-winged moths due to increased visibility against altered tree colors.
7. Natural selection highlights the evolutionary role in enhancing adaptability to environmental changes.
8. This process selects genes or traits ensuring optimal adaptability to prevailing environmental conditions.