These fluctuations may also affect the predators that feed on these prey items, such as wolves, foxes and owls. These predators must either find an alternate source of prey or risk starvation and death. Ecological Succession. When changes to either abiotic or biotic factors affect an entire ecosystem, ecological succession occurs.
A temporary decrease in blood flow to the brain results in unconsciousness, or fainting. Many disorders, some of them serious, can cause this.
Fainting, which medical professionals call syncope (pronounced SIN-ko-pea), is a temporary loss of consciousness. Fainting is caused by a temporary loss of the brain's blood supply and can be a sign of a more serious condition. People of any age can faint, but elderly persons may have a serious underlying cause. Fainting accounts for a small portion of emergency department visits and 6% of hospital admissions.