Sex On Venus
Sure enough, there's a race of advanced beings there and the two races exchange huge amounts of information. Inevitably, the questions turn to sex.
"How do you reproduce?" one of the Earthling NASA astronauts asks.
The Venusians are pleased to demonstrate. Two of them get together and touch tentacles in a special way. A moment later a sac appears on one of them, grows to the size of a basketball, and breaks open. A tiny tentacled baby pops out and falls to the ground, jumps up and starts running around looking for its first meal.
"Amazing!" exclaim the Earthlings.
"So will you give us a demonstration of how you do it" ask the aliens?
The Earthlings can hardly refuse, so the commander asks for volunteers and a couple steps forward and demonstrates Earthly delights. The Venusians are rapt with interested attention.
When the couple finishes, however, the aliens are confused. "Where is the child" they ask? "Or was the mating a failure"?
"Well", says the commander, "we don't find out right away. If it was successful, it takes a month or two to find out, and the baby doesn't show up for nine months after conception".
"Nine months" asks the incredulous alien leader? "Then why were they in such a hurry at the end"?