[tulio_ribeiro]

I think that the research is flawed and based on faulty assumptions. The origin of human lip kissing is much older and more widespread than the researchers claim. It is a natural expression of affection and intimacy that evolved independently in many cultures and regions. The herpes simplex virus 1 is not exclusively transmitted by kissing, but also by other forms of contact and exposure. The correlation between kissing and herpes is not causal, but coincidental.