How they hell do snakes choose if they are a boy of a girl?

Question

How do snakes choose what gender they wanna be??? I mean they can't just say I wanna be a boy and a **** pops out lol
How do they do it?

Answer 1

There are some cases of sex reversal among vertebrates, but snakes are not among them.
Snakes have the same "choice" that we have, that is to say, no choice at all.
The male or female condition of snakes is determined by a genotypic mechanism, similar to that of mammals; that is to say, a particular combination of chromosomes will determine "boy" or "girl".
Among snakes, the females are (ZW), while males are (ZZ).

This contrasts with most other reptiles, in which the sex of the embryo is not decided by special sexual chromosomes at the moment of fertilization, but by the temperatures during the development of the embryo (Environmental Sex Determination).

This is an interesting article about this:
http://www.seaturtle.org/PDF/Ciofi_1997_AppAnimBehavSci.pdf


That being said, the copulatory organs of male snakes do not protrude from their body except during mating. This may lead people to think of snakes as a "she". However, males have a pair of hemipenises that are proportionally large, and quite impressive when everted from the cloaca. They look like translucent sacks or elongated balloons with spines and ornamentations. See this picture of a snake's cloaca showing the hemipenes (from the source below):
http://www.csus.edu/org/critters/CRITTERS/PICS/probe9.jpg

Answer 2

err.. who said snakes chose what gender they wanted to be? They're born either male or female, it's the temperature that plays the important role in determining the sex the eggs will have