A new species of fly was discovered on an island in the South Pacific. Several different crosses were performed, each using 100 females and 100 males. The phenotypes of the parents and the resulting offspring were recorded.
Cross I: True-breeding bronze-eyed males were crossed with true-breeding red-eyed females. All the F1 offspring had bronze eyes. F1 flies were crossed, and the data for the resulting F2 flies are given in the table below.
| F2 Phenotype | Male | Female |
| Bronze eyes | 3,720 | 3,800 |
| Red eyes | 1,260 | 1,320 |
Cross II: True-breeding normal-winged males were crossed with true-breeding stunted-winged females. All the F1 offspring had stunted wings. F1 flies were crossed, and the data for the resulting F2 flies are given in the table below.
| F2 Phenotype | Male | Female |
| Normal wings | 1,160 | 1,320 |
| Stunted wings | 3,600 | 3,820 |
Cross III: True-breeding bronze-eyed, stunted-winged males were crossed with true-breeding red-eyed, normal-winged females. All the F1 offspring had bronze eyes and stunted wings. The F1 flies were crossed with true breeding red-eyed, normal-winged flies, and the results are shown in the table below.
| Phenotype | Male | Female |
| Bronze eyes, stunted wings | 2,360 | 2,220 |
| Bronze eyes, normal wings | 220 | 300 |
| Red eyes, stunted wings | 260 | 220 |
| Red eyes, normal wings | 2,240 | 2,180 |
What conclusions can be drawn from cross I and cross II? Explain how the data support your conclusions for each cross.
What conclusions can be drawn from the data from cross III? Explain how the data support your conclusions.
Identify and discuss TWO different factors that would affect whether the island’s fly population is in Hardy-Weinberg equilibrium for the traits above.
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