Question

Many butterflies in the genus hellconius are mimetic, which means that they closely mimic the wing patterning and color of highly poisonous species. This is a benefit because many predators such as birds learn to avoid poisonous species by identifying their wing patterns/colors. Some closely related Heliconius species mimic different poisonous species. Although they can successfully hybridize and produce viable/fertile offspring that have high fitness in the laboratory, the hybrids are intermediate in wing patterning/color and are not good mimics. Consequently, they have low fitness in nature. This is an example of:

1) Intrinsic post-zygotic isolation
2) Haldane's rule
3) Extrinsic postzygotic isolation
4) Habitat isolation
5) Prezygotic isolation

Answer 1

The phenomena where Heliconius butterfly hybrids exhibit low fitness in nature because of their non-mimetic wing patterns is an example of extrinsic postzygotic isolation.

Step-by-step explanation:

The scenario described where Heliconius butterfly hybrids have low fitness in nature due to intermediate wing patterning/color that does not closely mimic either of the poisonous species from which they descend is an example of extrinsic postzygotic isolation.

This type of isolation occurs when hybrids are formed between two different species but are at a disadvantage in the natural environment because they do not fit into the ecological niche of either parent species. Their lower survival rates lead to reduced chances of passing on their genes, which in turn reinforces reproductive isolation between the two parent species. It is worth noting that the hybrids are fertile and can produce offspring in the laboratory, which indicates that their reduced fitness is due to environmental factors, and not intrinsic biological issues.