Final answer:
Parthenogenesis in sharks leads to less genetic diversity, which increases vulnerability to diseases and environmental changes compared to sexual reproduction that promotes genetic diversity and adaptability.
Step-by-step explanation:
Parthenogenesis could prove to be harmful to the survival of a species if it were the only method of shark reproduction because this form of asexual reproduction results in offspring that are genetic clones of the parent. Without the genetic diversity that sexual reproduction provides, a population becomes more susceptible to diseases, has reduced adaptability to environmental changes, and may exhibit an increase in the expression of deleterious mutations.
In contrast, sexual reproduction combines genetic material from two parents, producing genetically diverse offspring with potentially greater chances of survival in changing environments.