Why does Spider-Man shoot webs from his wrist in the movies?

Question

From what I remember, in the original comics, Spider-Man shot webs from his wrist because Peter Parker used his science background to design mechanical web shooters.

In the Sam Raimi movies, however, the webslinging is a side effect of the genetically-modified spider bite that gives him the rest of his powers.

My question is this: why would the spider DNA result in webs originating from his wrists? Natural spiders create webs with spinnerets located at the tip of their abdomen. Wouldn't it have been more believable if Spider-Man's webs came from, well, behind him?

Is there some explanation given as to why his web-producing organs appeared in his wrists, and not elsewhere?

Answer 1

There's no in-universe answer.

Out-of-universe, they would have had to complicate an already long-running movie to add in an explanation of Peter's father's inventions, how Peter finally solved the adhesive problem, his testing of the fluid, etc. It would have taken another 30-45 minutes to give any satisfactory explanation, which would have pushed the running time up to a fiscally inadvisable level.

The spinnerets become located in his wrists for no good reason. The only reason they're there is because that's where Spiderman's webs come from. Anything even approaching an accurate physical location would have taken the movie into an entirely different direction.

The studio would never have gotten behind that. It would have been a waste of their assets to even consider it.

Answer 2

Actually, scientifically and biologically it's fine for him to have spinnerets in his wrists. Research earlier this year has confirmed several species of tarantula (and therefore likely other spider species) really DO produce silk from their limbs as well as their abdomens; it's part of what helps them climb surfaces.

http://jeb.biologists.org/content/214/11/1874.abstract

Answer 3

They wanted to keep the classic Spider-man look with his middle and ring fingers touching his palms while spinning webs, which is why they come from his wrists.

On the DVD behind the scenes they talk about the change from the web-slinging technology to the organic spinnerets. Stan Lee said that if he had thought of the spinnerets originally he would have used that, but since he didn't he had to come up with a technological explanation.

Answer 4

There IS a reason Spider-Man shot organic webbing from the top of his wrists. But to know how this came about, you need a bit of Spider-Man lore that is overlooked in the movie. This was the costume that changed where webbing came from in Spider-Man lore nearly thirty years ago.

The Famed (or infamous) Black Costume, first seen in the Secret Wars (1984)

• Up to this point in Spider-Man comics, Peter Parker used his famously-home-designed web shooters which ejected a custom-made, super-strong, incredibly-adhesive, yet fast-dissolving polymer that Peter Parker called his webbing. (First seen in Amazing Fantasy #15)

• These webshooters were versatile and could create any number of uses for webbing from protective gear to handcuffs. Their greatest failing was they could run out of webbing and did so at the most inopportune times.

Then came 1984 and Marvel created a character called the Beyonder and the Secret Wars were born. One of Marvel's largest crossover events at the time (possibly one of the earliest) and it brought a wide array of Marvel's most well-known and well-loved characters together in a cosmic struggle including one Peter Parker.

The famed Black Costume was discovered during the Secret Wars run of stories and was an alien symbiote which bonded with Parker giving him a number of new abilities.

• He could change his costume's appearance to any street clothes he desired. For the first time, Spider-Man could change without having to duck into an alley, or a phone booth or hanging upside down on someone's fire escape.

• His speed and agility were increased as the symbiote augmented his existing powers further.

• The most impressive change which found its way into movies 30 years later was the position of his web shooters. Previously held under his wrist, Parker had to turn his hand upward and depress the stud to launch his webbing.

• His new organic web shooters were on the back of his wrist marked by a large white patch. The suit made its own webbing! And it appeared to have an inexhaustible supply. This location is the same location they used in the movie.

• If this character design seem familiar to you, it should. The suit and Parker had a falling out when it tried to take over his mind and claim Parker's body as its own. With the help of the Fantastic Four, Parker quits dating the suit and they agree to see other people.

• The first person who wore the suit was a fellow named Eddie Brock and he took the name Venom. The suit eventually spawned (don't ask) and produced other symbiotes, one of them took the colorful sobriquet, Carnage.

• When the movies decided to take on the genetic transformation to Spider-Man, they decided to go with the positioning of the organic webshooters seen on the Black Costume, maybe as tribute, maybe to be different. But anyone who knew the Black Costume smiled remembering the first time we saw it in action.

So now you know, true believer.