To the point - it is interesting to note that whether or not armor is useful at all, even for soldiers actually engaged in battle, tends to vary over time and place, and depend on the role of the soldier at issue - armor after all, while undeniably providing protection, tends to be at least somewhat mobility- and vision-hampering.
If some soldiers are willing to rationally discard armor because even in battle (when wounding is highly probable) the benefits of going without outweigh the risks …
And on the ‘not worth it’ side of the ledger, there’s the idea that given the general human body plan, the throat is the easiest to defend part of the body (eyes are able to see anything coming at the throat, hands are positioned to fend off anything coming at the throat, and in the extreme a fetal position with the head tucked covers the throat). So in most close-range fights if something is able to get pointy things on your throat, it’s probably pretty much won the fight – throat armor might delay it for a couple seconds, but it will just move on to the eyes, hands, femoral artery, etc.
Kind of like why there aren’t rifles stored on the bridge of a battleship – if you have a chance to use them, you’ve already lost.
It is clever. Mocking it doesn’t make it less clever.
Fighting ignorance, dude. Sometimes, ya gotta repeat yourself (re: purpose, etc).
To address your wording: Sometimes, there is no ‘why’ either. We don’t lack things because they would have negative consequences. ** Sometimes we just lack them. Period.**
Wait…Who says the neck isn’t protected? The spinal cord is there…inside the bones that make up your cervical spine. The jugular and carotid veins are there, but inside thick layers of fascia and muscle (plus, they’re so numerous that cutting just one isn’t really the instant death sentence Hollywood makes it out to be; the others will keep the important things oxygenated as long as you can get pressure on the cut to hold the blood in.) The trachea is made of rings of really tough cartilage that are hard to cut through even with a sharp scalpel, and even if it’s cut, you can still suck air in through the hole.
For a body feature as wonderfully flexible in nearly every direction as the neck is, it’s astoundingly *well *protected, iffen you ask me.
Course for those aquatic dudes, they’ve got the opposite issue- it’s damn cold out there in the ocean and they want to keep their vital bits warm!
What WhyNot said…
I’ve taken some hits to the back of the neck that I wouldn’t want directed at my eyes or nuts. I’m not convinced that the mass of tendons, muscles and pipes do not constitute armor. Put another way, baseball hitters supplement their skulls with additional protection: they don’t add gear to the side of their neck, do they?
Sport fans can discuss football padding and catcher’s helmets here.
Furthermore, I doubt whether hand-to-hand combatants necessarily prefer the neck to other targets: methinks there are superior ones for disabling an opponent. Then again, cougars probably target the neck with good reason.
Looking at Wikipedia, they apparently also have to keep them cool, and have a specialized cooling system do do so. The same article also mentions a number of mammals with internal testicles, and points out that external testicles are in fact the “basal condition” for mammals; most kinds have internal testicles.
I’m gonna quote that.
Pangolins, upper side only.
Thanks, DT, Ignorance fought.
Haha, thanks. 
We appear to populate the world with over 6 billion people. I’d suggest it’s clearly not a deadly error. We clearly don’t need to armor our necks, or we would have.
I have to add armadillos to Tamerlanes’s contribution of Pangolins.
Given that this forum is for factual answers to questions, I’m not sure why you are mocking attempts to give factual answers while engaging in speculation.
The article states that internal testicles is the “basal” condition. “Basal” means that the earliest members of that group had that feature.
I’m not seeing where it says that most “kinds” have internal testicles, although I don’t really know what you mean by the term “kinds”-- “species”? If so, I seriously doubt it, considering that 70% of mammalian species are either rodents, bats or shrew/mole-like creatures.
That’s one of the main ways that evolution works - the “fitter” individuals survive to have lots of children to pass on the helpful traits and the less fit have fewer children or none at all, either because they die before reaching fertile age or they can’t find a willing partner.
This is one of the reasons why Alzheimer’s Disease won’t ever be evolved against (absent a massive forced Eugenics campaign with the ability to predict Alzheimer’s) , since Alzheimer’s Disease doesn’t normally strike or even become reasonably detectable until a person is beyond normal reproductive age and they have had as many children as they are ever going to have.
It’s possible that humans never developed a significant neck armor mutation that provided any sort of material advantage that could be naturally selected (e.g. a mutation that would give an edge in combat, fall survival, etc.). If there are no instances of the mutation, any fraction or multiple of zero is zero.
It’s also possible that humans did at one time have a neck armor mutation, but the downsides/side effects were so bad (perhaps the armor was so heavy it broke your spine by age 10) that it was difficult for children with the mutation to achieve parenthood, and so the trait was evolved against.
I agree with the arguments for reduced neck mobility. I also agree that anything able to kill us with a bite to the neck would be able us kill us if even if we did have neck armor. These are surely sufficient answers.
But I’ll toss out another idea: There’s a hypothesis that humans evolved as run-in-the-heat specialists. Neck armor would slow us down and reduce our ability to shed heat.
It looks like an artichoke with legs.
Awesome.
OK. Let’s revisit the OP and break it down:
The “neck” does not have a 100% kill certainty or anything close to it. Do you mean the Spinal Cord-- the thing protected by the vertebrae. The vertebrae is like the rib cage is like the skull. And note that the rib cage does not protect much more than the heart and lungs. And even at that, it’s full of holes.
See above
The spinal cord is not “right there”. It’s protected by a bony enclosure. The jugular is like the femur and other major arteries.
Not really sure what this means.
All of our traits started out as “mistakes” in the sense that mutations are errors in copying the genetic code.
And yet it hasn’t proven to be so. Just looking at primates, none has neck armor. And yet* H. sapiens* has the largest number of members than any primate (~7 billion), or any large mammal, for that matter. In what sense could that be deemed “deadly”?
And birds, which unlike reptiles and fish are also warm-blooded creatures. They have all their boy parts on the inside, and scientists say their testes simply endure their core body temperatures.
Tell that to Rambo’s victims.
