Evolution of life is what Charles Darwin elucidated in his Origin of Species which was partly a summary of his observations on his lengthy trip to South America. Basically, it is whereby all organisms whether plant or animal exhibit variations such as keener vision, ability to run more rapidly etc and the variations that are beneficial to the organism that help it to survive especially in changed environments are naturally selected and after some time the organisms with the beneficial varieties become new species.
The coil generates a stronger magnetic field. The coil generates a weaker magnetic field. The field generated by the coil has a different polarity than the field generated by the length of wire.