Timothy inherited attached earlobes because his maternal grandfather had homogenous genes for attached earlobes. Along with this, the woman that his grandfather married and had offspring with either had homogenous genes for attached earlobes, or had mixed genes so both of his grandparents passed on the recessive trait for attached earlobes.
Timothy inherited attached earlobes through a recessive genetic trait passed from his maternal grandfather. His mother, who likely has one recessive allele, contributed to Timothy's genotype of aa, leading to his attached earlobes. The inheritance follows standard Mendelian genetics, where a recessive trait can appear even when parents have dominant traits.
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