Darwin Vs. Freud: How The Brain Evolved Sibling Recognition

Sigmund Freud once expressed his view that family members are the first and most powerful objects of sexual desire. However, a recent study indicates that biological evolution favored the recognition of siblings within a family unit, thus enhancing altruism towards those individuals and naturally preventing incest.

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Fundamental theories in evolutionary biology have long proposed that biological kinship is the foundation of the family unit. It not only creates the sense of altruism that exists among genetically related family members, but also establishes boundaries regarding sexual relations within the nuclear family. Questions have persisted, however, regarding the means by which humans recognize family members – particularly siblings – as close genetic relatives.

Source: Science Daily

This is something I thought had been discovered a long time ago, but a new study just surfaced. I'd appreciate any comments on this, as the article contradicts the common notion that the family unit is culture-dependent.

It's sort of like those stories you hear about siblings seperated at birth who end up working next to each other for years before discovering they are siblings. They usually say they just had some sort of connection with the other person. In an opposite sex thing, often they are best friends but don't date each other. I think it's just something in our DNA. We just know.

Actually, the brain is wired for recognition of the sibling from observation. There are similar cases of children who were not blood-related, but who were raised together; they ended up considering each other siblings and the altruism/lack of sexual interest worked as if they shared the same biological parents.

I haven't got any information about blood-related individuals separated at birth and re-united later. But just remember the legend of Oedipus and Jocasta, each ignoring the fact that they were mother and son. But of course, this is only a legend...

Perhaps it's not genetic or biological, but instead, a level of imprinting we are not yet aware of, as a newborn imprints with mom, then dad, this might continue through out infancy with other family members as well, what i would like to see are the results of a study, where altruism has been discarded and find out if those who have desires or acted sexually with a sibling, were always the eldest sibling, not having the other siblings to imprint with.

Just a thought!

TSG!

According to the study, the 'wiring' in the brain that allows for sibling recognition starts very early and carries on as the child grows up. So, even for an older sibling, seeing the younger one being taken care of by the parents sends the information to the brain for sibling recognition. The reported cases of incest between siblings are most probably pathological and due to an absence of the required 'wiring'. Now, it would be interesting to determine what caused it.