Have you ever been underwater?   Scuba divers carry their own source of breathing gas,
yes i like scuba diving
Unfortunately, Immersion in water and exposure to high ambient pressure have physiological effects
wow i havent been that deep before
 Humans are not physiologically and anatomically well adapted to the environmental conditions of diving
thats why i always wanted to be a fish, i love water
Ecology
Ecology (from , "house", or "environment"; -λογία, "study of") is the branch of biology which studies the interactions among organisms and their environment. Objects of study include interactions of organisms that include biotic and abiotic components of their environment. Topics of interest include the biodiversity, distribution, biomass, and populations of organisms, as well as cooperation and competition within and between species. Ecosystems are dynamically interacting systems of organisms, the communities they make up, and the non-living
Underwater diving
Underwater diving, as a human activity, is the practice of descending below the water's surface to interact with the environment.
Immersion in water and exposure to high ambient pressure have physiological effects that limit the depths and duration possible in ambient pressure diving. Humans are not physiologically and anatomically well adapted to the environmental conditions of diving, and various equipment has been developed to extend the depth and duration of human dives, and allow different types of work to be done.
In ambient pressure diving, the