To determine the dangers of eating salmon which are contaminated by mercury you need to search for the dangers of mercury poisoning. This should be the first step for the research.
Question: Which of these would be best to use as the basis for an Internet search of whether the levels of mercury in salmon make eating it unsafe?
The "diving reflex", or bradycardic response, is the natural reflex of infants on water, is an automatic response that they lose later in development, and it comes in order of survival mode and has an evolutionist logic.