Final answer:
The number of species tends to increase with the distance from the city center or the size of the habitat. Speciation is more likely to occur when there is a greater distance between two groups of the same species. Habitat loss or fragmentation leads to a decrease in the number of species.
Step-by-step explanation:
The relationship between the number of species and the distance from the center of the city is similar to the relationship between an island's area and the number of species present on the island. As the distance from the city center or the size of the habitat increases, the number of species also tends to increase. However, this relationship is not linear; it follows a curve.
Scientists have found that as the distance between two groups of the same species increases, speciation is more likely to occur. This is because as the distance increases, the environmental factors between the two locations become less similar. Different ecosystems, behaviors, and habits can lead to evolved differences in the species, ultimately resulting in speciation.
Similarly, when habitats are fragmented into smaller pieces or when there is habitat loss, the number of species decreases. The species-area relationship shows that smaller fragments or reduced habitat sizes result in fewer species. This is because smaller fragments have lower diversity of habitats, support smaller population sizes, and represent a smaller sample of the original habitat.