Answer:
I'm sure there's some truth to the idea that if you don't have time to be depressed, you won't be. When I first noticed something more than unhappiness, it was about getting out of bed in college. Monday through Friday I did what it took to get to class. I don't remember feeling anything. But some Saturdays and Sundays it was amazing how little energy I had to get out of bed, not mere laziness, but a dead feeling.
This is not just about psychology. Patients with Parkinson's can suddenly move much better in a crisis such as a fire. The brain circuits that tell us it's time to panic or something not quite that do have an effect. So life and death situations would have masked depressions for those who lived long enough for depression to be likely. But how often did our ancestors really face life and death? Warfare was not common until after the agricultural revolution. There were no spoils to fight wars for until then.
It's bad if you don't take care of the hunting/gathering or the crops, but that might take as long to destroy your life as not going to work today. Depression in the past might have been a lot like today, but interpreted differently.
However much depression is genetic, it must have some reason to persist in the population. How much reason depends on how much these genes are actually present. Do whatever genes that cause bipolar diorder exist just in the 2% of people who are bipolar, or are those 2% the ones who combine several genes that are much more common individually? Is the evolutionary payoff for the genes that cause bipolar disorder to be found in periods of higher productivity or just having a lot of sex or something else? Is the payoff for any mood disorder not in the disorder itself, but in lesser expressions of the same genes that make people more sensitive, more emotional, more successfully romantic, leading to more sex and more offspring?
Sometime later in this century there will be answers to these questions. Once all 20,000 of our genes are understood, some of them will certainly be represented more in those with mood disorders. Variations in DNA sequences will let researchers track their history just as Y-chromosome analysis tells a story of male human migration today. I bet these genes didn't just start recently. What exactly their payoff is will be interesting to know. Maybe it's simple. Maybe it's complex. Maybe it's predictable. Maybe it's beyond what anyone today would guess. I like the idea that this is something that inevitably will be understood. Then once it's clear what is genetic, that will leave what's not genetic to be better understood as well. That will be so much better than speculation.
I believe that early man was so busy surviving that he had little time to be depressed. During the day he would be hunting - a dangerous activity. He would likely be exhausted at nightfall, perhaps huddled around a campfire, terrified of predators and of evil spirits that he supposed were all around him. With our leisure time, only we have the luxury of being depressed. By the way when we say early man it is meant to include both sexes.
Wouldn't you be depressed. going home to a cold cave and sleeping on a dirty old skin,after a hard days hunting!.
No early man had depression it's to slow you down so you don't need so much energy. Alcohol was early mans first treatment for depression.
Maybe a little discontent but depressed? They didn't have much time for that. They grew their own food, killed their own meat, NO grocery stores--no modern conviences--stop and think about what you have that they didn't. They didn't even have toilet paper--nor bathrooms. They had no doctors--as such. They didn't have lumber to build, If they sat around depressed, they would die--if they sat around they would die. You had to walk everywhere you went. (unless you had an animal to transport you and they you had to rovide food and water for than animal. Think about it. My opinion is that the modern world is the cause of depression.
No, he was too busy raping and pillaging. Then again, maybe there was a few downtimes in between bursts of bloodlust.
of course
That's interesting because i watched a documentary about the early man and they were quite caring. The females sometimes had there new babies taken away and killed because it meant the breastfeeding mothers needed more food, sometimes they couldn't afford this. The mothers were shown to be very distressed at having the babies taken away. They buried the dead too like they cared about them, graves with stones on top and there possessions with them, why bury them with such thought? Surely these emotions could mean that they would feel depressed?