population bottleneck

A population bottleneck occurs when a large population experiences a sudden and drastic reduction in numbers due to events like natural disasters or habitat destruction. This sharp decline can cause a loss of genetic diversity because only a small group survives and reproduces. As a result, the genetic makeup of the future population may be less varied, limiting its ability to adapt to new challenges. Once the bottleneck ends, the population may grow again, but its reduced genetic diversity can have long-term effects on health and survival.