This represents the example of founder effect.
The founder effect is a term in genetics that describes the loss of genetic variation as a result of new population formation by a very small number of individuals from a larger population. Small group of migrants (the afrikaner population of south Africa) that is not genetically representative of the larger population (Europe population) forms a new population with lower genetic variation.
A dominant trait can be shown both when an organism is homozygous dominant AND heterozygous. Two different genotypes give the same visible result so a testcross is needed to be able to accurately say if the organism is homozygous dominant or heterozygous
The main function of the circulatory system is to move blood and lymph<span> through the body. Doing this transports nutrients and oxygen to the cells of the body and removes waste products such as carbon dioxide.</span>