There are many ways that an ecosystem can lose it's equilibrium or balance.
A few potential causes can be, the introduction of a new species, the sudden death of some species, and natural hazards (weather related or seismic changes). Lastly, one of the biggest causes are man-made hazards.
The best answer in terms of how organ cultures are an improvement on this transport method is "<span>Cultured organs can be kept alive for several weeks before transplant."</span>
