spontaneous mutation
Technical term in genetics referring to a mutation that occurs naturally, without artificial induction.
Spontaneous mutation is considered one of the driving forces of evolution.
In this experiment, we compared spontaneous mutations with artificially induced mutations.
突然変異 is a broader term for 'mutation' and can include both spontaneous and induced mutations, while 自然変異 specifically refers to mutations that occur naturally.
Compound of 自然 (natural) and 変異 (variation, mutation). The term is a direct calque from English 'spontaneous mutation' used in genetics.