Approximately what percentage of the energy in one trophic level becomes incorporated into the next level?

One of the purposes of transcription is to produce a sequence of bases that

The idea that all living things are made up of cells is considered scientific law. this means the idea is an emerging scientific idea that has a logical explanation. has been tested with similar results at least twice. is supported by scientific consensus and a large amount of evidence. has been rejected only once by the scientific community

Scientists discover two populations of mice on either side of a major river. the two populations have almost identical genes but the mice from one side cannot breed with mice from the other. this is most likely because