What does the term “endemic species” mean in the context of freshwater biodiversity?

The term “endemic species” refers specifically to species that are native to a particular area and are found nowhere else in the world. In the context of freshwater biodiversity, this means that these species have evolved and adapted to live in unique aquatic environments, such as specific lakes, rivers, or wetlands. Their presence is often linked to the distinct ecological conditions of their habitat, which can include factors like water chemistry, temperature, and the surrounding landscape.

Endemic species are essential to the study of biodiversity because they can provide insights into the evolutionary processes that shaped their development. Additionally, they may be particularly vulnerable to environmental changes or habitat loss, making their conservation critical for maintaining the ecological balance of their specific freshwater ecosystems.

The other options describe different types of species interactions or distributions that do not align with the specific definition of endemism. For instance, species that migrate long distances for breeding, thrive in a range of habitats, or have been introduced by humans all demonstrate different ecological dynamics that do not focus on the concept of being unique to a specific locale.