Final answer:
The statement is true; giraffes' long necks are an adaptation allowing them to reach high leaves and survive better in their environment, leading to the long-neck trait being passed to offspring.
Step-by-step explanation:
The statement that "A long neck is a physical adaptation that helps a giraffe survive in its environment" is true. Giraffes with longer necks had a significant survival advantage because they could reach leaves high in trees that were out of reach for other animals. This trait would increase their fitness, given that they could access a food source unavailable to others, leading to higher rates of survival and reproduction among the long-necked giraffes. As a result, the long-neck trait was passed down to subsequent generations, and over time, it became a characteristic feature of the species.
Similarly, long-necked tortoises in the Galápagos Archipelago exemplify how animals well-suited to their environments survive better in harsh conditions. The tortoises with longer necks could access more food, particularly during times of scarcity like droughts, giving them a better chance to survive and reproduce. This process of natural selection eventually led to populations where only the long-necked individuals remained.
Through this process, it's evident that the long necks of giraffes are an adaptation shaped by their environment to help them survive, an example of natural selection in action.