why not
A transportation barrier is a natural barrier like mountains, rivers, oceans, etc that blocks or slows the way of transportation.
because they form a natural barrier
There are many types of animals that live in rivers. Raccoons, snakes, fish, frogs, platypus, and otters are all animals that stay in the rivers.
A physical barrier is a tangible, often structural feature that prevents or limits access to an area, such as walls, fences, or natural obstacles like rivers and mountains. In contrast, a mechanical barrier refers to devices or systems designed to obstruct movement or flow, such as locks, gates, or security systems. Both types of barriers can serve protective or controlling functions in various contexts, from security to environmental management.
aquatic animals
Drought
Drought
It is a natural feature
Rivers belong in the physical realm, but may also be shown on a political map.
An ecological barrier is a natural or human-made feature that restricts the movement of organisms across a landscape, such as mountains, rivers, roads, or urban areas. These barriers can hinder gene flow, change habitat connectivity, and impact the distribution and diversity of species within an ecosystem.
When a population is separated by a barrier, it is referred to as "allopatric speciation." This process occurs when physical barriers, such as mountains, rivers, or human activities, divide a population, leading to reproductive isolation. Over time, the separated groups may evolve independently, potentially resulting in the emergence of new species.
Fish.