The horrible truth about Spiderman’s Anatomy

striped lynx spider (Oxyopes salticus)I was on a panel a few weeks ago discussing mutations, and what they can and cannot do.  Spider-man was one of the topics, because the sad truth is that the Comics industry has conspired in a G-rated cover-up to hide his terrible, terrible affliction.

Spider-man’s spider webbing talent isn’t what you think it is.  Sure, male spiders do have special appendages on the front of their bodies–they are really noticeable “boxing gloves.”  They actually can be up to 20% of a male spider’s body weight.

Those are not, however, what spiders shoot silk or webbing out of.  These pedipalps have one function. SEX.

That white, sticky stuff Peter Parker is shooting out of his wrist? Um. Yeah.

frame from amazing spiderman #503

This is what guys discovering they are covered with spider jizz look like.

There is a reason that people freak out when he shoots a big blop of splooge at them.

See, spiders have a very odd reproductive system. Male spiders don’t have a penis.  (I don’t know if a side effect of Mr. Parker’s radioactive spider bite was his penis falling off, but that might explain his perpetual whiny attitude.  Even if if he did manage to initially retain his penis, it probably broke off later during mating with Mary Jane.)

Pedipalps are modified appendages at the front of a male spider.  They use these to insert sperm into a female’s body.   To get the sperm out of his gonads in the rear, a male spider creates something called a “sperm web” that he limbos underneath and deposits sperm onto.

He then turns around and “loads” the sperm into his pedipalps, and sets off to find a female and hook up.  Pedipalps are the spider equivalent of a turkey baster.

Don’t see the parallel? Let’s review how Mr. Parker’s “slingers” work.  His arms are modified appendages at the front of his body. He has to “load them” with “fresh wet-fluid.”

NOW YOU KNOW THE TRUTH.

“But, Bug Girl!” You say. “You don’t understand the story!” Ok, let’s suppose, for your collective mental sanity, that Mr. Parker is actually shooting spider silk, not nocturnal emissions, at villains.

The business end of a spiderSpider silk glands are located anterior to the anus, and posterior to the gonads.  If the radioactive spider had actually given Peter Parker silk glands? He would shoot webbing out of his taint.

Is that….an improvement?  I can certainly see why Spider-man would prefer to gather up the silk and dispense it from a gizmo on his arm, rather than have a little flap in the back of his leotard.

If you would like to look at male spider pedipalps in action, check out this video.  The naughty part begins at 2:35 — note that it really is very much like a turkey baster in function!

MORE HORRIBLE TRUTH:

Scientifically Accurate Spider-Man (is not accurate)

Can Stick Insects really mate for 1400 hours?

I saw this tweet a while back, and it made me awfully curious:

stick insects can have sex for 1400 hours

Is that true? Because that seems like not a very smart thing to do, if you are a large and tasty insect.  Or, in this case, two large leaf-eating insects belonging to a group that specializes in being invisible to predators by looking like a stick.  Two sticks having sex is the sort of thing I’d notice, anyway.

mating insectsThe risk of predation while you are making out–or more literally “hooking up” in the case of insects–is a major issue.  You can see from this photo that a fair amount of Kama Sutra-ish contortion is needed to successfully maneuver into place.  This does tend to inhibit one’s ability to run away!

Several different papers I read repeated that stick insects have remained paired for up to 79 days, but I was not able to see an actual reference with the original details.  Some of the references cited date back to 1910, so not surprising that I can’t get my hands on a digital copy.

From one paper describing mating behavior:

“The Indian stick insect Necroscia sparaxes may remain coupled for up to 79 days (a record for insects)”…Intromission may occur only initially or intermittently. In either case, a substantial proportion of male time-investment is not spent in ejaculate transfer. 

In captivity, Diapheromera veliei and D. covilleae pair for 3 to 136 hours and the penis may be inserted and removed up to 9 times. The genitalia are not in contact for ca. 40% of this period, and attachment is maintained by a male clasping organ.

It’s generally thought that the male hangs around in order to have repeated matings, but also to drive off other males that want to get lucky. I found several reports of stick insect menage a trois (or sept) in the literature, including this etching of kinky stick insect activity.  The male is–literally–cock-blocking a competitor.

So, it’s probably correct to say that stick insects can remain paired for up to 79 days, even though I can’t verify that directly. It is less correct to say that they “have sex” for 79 days, just as it would not be technically correct to say you mated for 8 hours if you had sex at 10pm and again at 6am.  Well, unless you are into that tantric stuff, anyway.

Snce 1400 hours = 58 days, the numbers don’t match up, and it is not correct that stick insects mate for 1400 hours.   It’s more like 1,896 hours!

References:

Sivinski, J. (1978). Intrasexual Aggression in the Stick Insects Diapheromera Veliei and D. Covilleae and Sexual Dimorphism in the Phasmatodea, Psyche: A Journal of Entomology, 85 (4) 405. DOI: 10.1155/1978/35784