It looks like any other mouse. It is small, squeaky and covered in fur and spends its time sniffling around a cage. But this mouse is special. It is one of the first animals ever to be born without a mother.

Scientists in China have managed to create a bi-paternalHaving two genetic fathers. mouse. Researchers combined genetic material from two male mice to create an embryoA fertilised egg that is developing into a foetus. that inherited no female DNADeoxyribonucleic acid is the material in an organism that carries genetic information..

Nearly all animals have male and female members. ReproductionThe process of having offspring, or babies. occurs after a female egg is fertilised by the male. 

But now scientists are finding ways to create animals with two same gender parents. We have pushed beyond the laws of nature.

Many previous attempts have failed. Most embryos have not made it to birth. Those that do have died quickly due to health problems. Only a very small number make it to adulthood. And those that do are themselves unable to reproduce.

Yet it still represents a breakthrough moment. We have managed with mice. Will we soon be able to create new humans with two biological mothers or fathers, rather than one of each?

This would have enormous implications for life on Earth. Human society is organised around the idea of reproduction between men and women. It informs customs like marriage and inheritanceThe rules that determine how characteristics, like eye colour, are passed from parents to children. Or physical items or money that is left to you by someone who has died. .

Same-sex couples currently have to rely on a third party to have a child. This would change that. It could also further loosen the roles that mothers and fathers play in the lives of their offspring. Gender could become more fluid.

The fact that same-sex couples are unable to have biological children causes prejudiceAn idea about something, especially a group of people, that is not based on reality. . This might change in a world where a child can have two fathers.

This might seem a long way off. But there are other advances that suggest bi-paternal and bi-maternal children might be just around the corner. In 2018, scientists in Japan announced they had created human eggs from blood cells. 

Yet others advise patience. Science writer Helen Pitcher says: "For the foreseeable future at least, the stakes are too high, and the process too unpredictable, to consider using on humans."

Could two men have children one day?

Yes: Certainly not tomorrow, and probably not the day after. But the rapid advances in the past few years suggest that the bi-paternal man will be here sooner than we think, for better or worse.

No: It is one thing to create a mouse with two fathers. But the ethical headache of creating a new type of human with a low chance of survival and the inability to reproduce is too much to stomach.

Or... They can already. We need to move beyond the idea that biology determines real parenthood. If two men have a baby via a third party, that still makes both of them parents.

Bi-paternal - Having two genetic fathers.

Embryo - A fertilised egg that is developing into a foetus.

DNA - Deoxyribonucleic acid is the material in an organism that carries genetic information.

Reproduction - The process of having offspring, or babies.

Inheritance - The rules that determine how characteristics, like eye colour, are passed from parents to children. Or physical items or money that is left to you by someone who has died.

Prejudice - An idea about something, especially a group of people, that is not based on reality.