What is one effect of the loss of genetic diversity in honeybee populations?

The loss of genetic diversity in honeybee populations primarily affects their resistance to diseases. Genetic diversity plays a critical role in a population's ability to adapt and survive in changing environments. When honeybees have a limited gene pool, it can result in a population that is more susceptible to diseases and pathogens. This is because diverse genetic traits often confer different resistances and strengths, enabling a population to fend off various health threats. By losing genetic diversity, the overall resilience of the population diminishes, making it easier for diseases to spread and impact colony health.

In contrast, other options would not relate directly to genetic diversity. Increased production of royal jelly and improvements in nectar gathering or hive temperature regulation are typically influenced by environmental factors, hive management practices, or specific breeding programs rather than genetic variation within the population. Due to the significance of genetic diversity in maintaining the health and survival of colonies, decreased resistance to diseases is a major consequence that highlights the importance of maintaining a robust genetic pool within honeybee populations.