According to David Bus:

* Physical reasons such as to reduce stress ("It seemed like good exercise"), feel pleasure ("It's exciting"), improve or expand experiences ("I was curious about sex"), and the physical desirability of their partner ("The person was a good dancer").

* Goal-based reasons, including utilitarian or practical considerations ("I wanted to have a baby"), social status ("I wanted to be popular") and revenge ("I wanted to give someone else a sexually transmitted disease").

* Emotional reasons such as love and commitment ("I wanted to feel connected") and expression ("I wanted to say 'thank you'").

* Insecurity-based reasons, including self-esteem ("I wanted the attention"), a feeling of duty or pressure ("My partner kept insisting") and to guard a mate ("I wanted to keep my partner from straying").

Whew... that's cleared up now. But why do you have sex?!!?

Omni Brain now has a Facebook group. Join us!

I'm amiss in reporting recent IRL social news. There was a lovely dinner with SciBling Bora (who's creating a new online community at PLoS) at the sustainable foods Italian restaurant Incanta, in San Francisco.

Then in Vancouver, Bjoern Brembs was in town for the Eighth International Congress of Neuroethology and we filled ourselves with talk of drosophila and free will, invertebrates vs. vertebrates, and all you can eat sushi.

We were accompanied by a mystery blogger who I won't say anything about but I must say congratulations on the new grant. Cheers!

I'm not sure how to feel about this video. Can someone inform me of the correct emotion?
Thanks.