I thought better of it to say "Lets do it"

We all know dogs greet by sniffing genitalia to check who it is but untill now I never knew elephants do the same!
While editing video I noticed in a number of cases where an elephant with its trunk would check out the genitalia of another elephant.
I now have hours & hours of video to check but take a look at this
[URL=http://www.youtube.com/watch?v=iHSD5LFKPAY]Watch at 2.36 for the trunk[/URL]

I expect this is a well known fact but I have never ever noticed it before.

I had to watch the film 3 times before I could see it. Who said Lord Kipper needs glasses?
Looks like you have noticed something quite new - I will keep an eye out as well to spot this.

Kipper: I see it all the time both in Amboseli and Tsavo. Usually it is a musth bull checking to see if a female is in estrous or not. Not only will he sniff with his trunk but sometimes will then put his trunk in his mouth to "taste" the smell. I've seen females not in estrous deliberately backing into a musth bull as though to say "check me out". After he checks, he then walks off and leaves the female and her baby alone, still looking for an estrous female.

To check if the bull is in musth, look and see if he is dribbling urine. If he is, he's not just an old man, he is in musth. He may also have temporal gland secretions running down his face. At the beginning of the musth urine dribbling may be sparse, but gets heavier the farther into musth he comes. Af he gets toward the end of musth, the dribbling decreases and then stops. Periods of musth last different times. When a young bull first start in musth he might be in musth for only a few days. The older, larger bulls will often be in musth for as long as 4 - 6 months. If a younger bull in musth meets and older, bigger bull in musth - the younger one almost always immediately drops out of musth and will leave the area. When we see the young bulls play fighting, it isn't only for fun. They are remembering in their huge brains which bull is bigger and stronger so they don't end up having to fight the stronger ones. It is often when two equally matched older bulls both in musth, enter the same areas with estrous females around that fights, sometimes to the death can occur.

Where you do self-drive safaris, you do need to be aware of these things. Musth bulls, even those that are normally placid, can become very dangerous due to the high testosterone levels - so give them plenty of room and don't appoach.

I also have video & photo's of males checking males so I dont think it's a male checking to see if a female is in estrus.
It was a Batchelor herd of young males when joined by an older male that I first noticed this happening.

They could use "crotch sniffer elephants" at the airports to check for explosives!

Excellent Kat, the quip of 2009!