I'm not sure how I feel about animal organs being transplanted into humans, but it could become a possibility soon.
Scientists have transplanted pig hearts into five baboons. One of the hearts has been kept healthy for more than two years, beating all previous records. The hearts were genetically modified to help stop them being rejected by the baboons' bodies.
The scientists hope that one day something similar could be done with humans. Could this be the solution to organ donor shortages?