In some situations, this makes quite a mess of the neat and tidy tree diagram, and calls into question where the precise 'species' cutoff is. "Interbreeding and genetic exchange have likely played a ...

Modern humans descended from not one, but at least two ancestral populations that drifted apart and later reconnected, long before modern humans spread across the globe. Using advanced analysis ...

The genetic code is a set of rules defining how the four-letter code of DNA is translated into the 20-letter code of amino acids, which are the building blocks of proteins. The genetic code is a ...

The diagram shows the chromosomes of three different people. Individuals A and B both have brown eyes, even though A is heterozygous and B is homozygous (dominant). Only people with a homozygous ...

Each gene might have different forms, and these are called alleles. The diagram shows the relationship between the cell, its nucleus, chromosomes in the nucleus, and genes.