Biologists have found more than 500 species of fruit flies on the various Hawaiian Islands, all apparently descended from a single ancestor species. This example illustrates
a. Polyploidy.
b. Temporal isolation.
c. Adaptive radiation.
d. Sympatric speciation.

Verified step by step guidance

1. Understand the concept of adaptive radiation: Adaptive radiation occurs when a single ancestral species rapidly diversifies into many new species, each adapted to a specific ecological niche. This often happens in isolated environments, such as islands, where there are many unoccupied niches.
2. Analyze the scenario: The problem states that more than 500 species of fruit flies have been found on the Hawaiian Islands, all descended from a single ancestor species. This suggests a process where one species diversified into many species to exploit different ecological opportunities.
3. Eliminate unrelated options: a) Polyploidy refers to the duplication of chromosomes, which is common in plants but not relevant here. b) Temporal isolation refers to species being reproductively isolated due to differences in mating times, which is not mentioned in the problem. d) Sympatric speciation occurs without geographic isolation, but the Hawaiian Islands provide geographic isolation, making this less likely.
4. Focus on the correct option: c) Adaptive radiation is the most fitting explanation, as it describes the diversification of a single species into multiple species in a geographically isolated environment like the Hawaiian Islands.
5. Conclude: The example of fruit flies on the Hawaiian Islands illustrates adaptive radiation, as it involves the diversification of a single ancestor species into many species adapted to different ecological niches.

Key Concepts

Adaptive Radiation

Adaptive radiation is an evolutionary process in which organisms diversify rapidly into a wide variety of forms to adapt to different environments. This often occurs when a species colonizes a new habitat with diverse ecological niches, leading to the emergence of new species from a common ancestor, as seen with the fruit flies in Hawaii.

Speciation

Speciation is the evolutionary process by which populations evolve to become distinct species. It can occur through various mechanisms, including geographic isolation, reproductive isolation, and adaptive radiation, where a single ancestral species gives rise to multiple new species adapted to different environments.

Common Ancestry

Common ancestry refers to the concept that different species share a common ancestor from which they have diverged over time. This principle is fundamental to evolutionary biology, illustrating how diverse species, like the Hawaiian fruit flies, can evolve from a single ancestral species through processes such as adaptive radiation.