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Despite tongue rolling being probably the most commonly-used example of a genetic trait in humans, it is a myth that a single gene is responsible for the skill. Studies demonstrate that tongue rolling is influenced both by genetics and by the environment. 1)
Humans have only 46 chromosomes. The mammal with the most chromosomes is the visceral rat. The North African blue atlas butterfly has between 448 and 452 chromosomes. It has the largest number of chromosomes of any multicellular aerobic organism. 2)
The amount of eumelanin and pheomelanin determine the hair color in humans. Eumelanin is dark brown, and pheomelanin is reddish. People who have large amounts of pheomelanin have red hair. 3)
The Drosophila melanogaster is a small insect from the order of flies that lives on rotting fruit. It is an invertebrate organism. Due to its easy breeding, simple crossbreeding and rapid growth, it was used by Thomas Morgan in his research on the chromosome theory of heredity. 4)
Johann Friedrich Miescher (1844-1895) was a Swiss researcher of cell metabolism and the discoverer of nucleic acids. In 1869, he isolated nucleic acids, which he called nuclein, from oil-soaked bandages of patients. He later discovered that they are found mainly in chromosomes. 5)
Only three genes are associated with sight, two with hearing and five with taste, while 1000 are associated with smell. 6)
It is a myth that earwax is dependent on genetics. A single gene is not responsible for the kind of earwax one has, whether it is wet or dry and what color. The wet wax allele is also not dominant over the dry one. 7)
Batology is the science that deals with the study of blackberries. Narrow specialization in the study of this genus serves to understand the very complex variation at the genetic and morphological level of blackberries, consequently also the systematics of these plants. 8)