Marmosets swap brain cells with their siblings

A large number of cells within the brains of marmosets actually come from their siblings, potentially influencing their behaviour – and the same may be true of human fraternal twins.

We already know that marmosets, small monkeys native to South America, carry their siblings’ cells in their blood. This is because, unlike other primates, most marmosets have non-identical twins or triplets, which exchange blood cells while in the uterus via a shared circulatory system. These swapped cells are retained after birth, meaning that up…