Answer:
Nutrients makes the most sense.
The best explanation that best predicts what happens to the trait over time is that the incidence of mid-digital hair will not change because it offers no selective advantage or disadvantage. A mutation is a sudden, spontaneous random change that occurs in the genetic make up of an organism. The presence or absence of mid-digital hair is controlled by a single gene with two alleles, and the allele H is dominant.
They are inherited from different parents
Crossing over does helps in genetic diversity as it provides with new genes combinations. In crossing over, chromatids exchange genetic information during the meiosis. This mixing of genetic information provides the offspring with its own unique genetic makeup with some similarities with the parent’s genetic system. Crossing over is very beneficial in terms of giving the offspring more variability that helps in becoming more resistant to a disease and be a better version than parents.
Lots of hand waving as is in the current field of much of molecular biology. Other than that experiments and observations. Basically the utilization of the scientific method and then trying to find the mechanism by which something occurs through even more research/experimentation.
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