10,000 BCE is roughly the end of the most recent ice age. I would expect biomass, especially at the higher end of the food chain, to be unusually low at that time.

Do you have numbers for 6000 BCE? I would think that would be a more accurate comparison as human impact is still low, but animal populations would have had plentiful time to rebound.

I am not trying to undermine your point, it is very valid and thought provoking. I would just recommend using a base number that is less vulnerable to criticism. Even if the base number for 6000 BCE is more in the 350-400 range, the contrast against the current 1800 level is still eye popping.

The estimation technique used for 10,000 BCE was to take the total estimated biomass for wild and domesticated animals along with human beings, from the estimate Vaclav Smil made for 1900, and use that as the prehistoric wild animal mass. So this represents an estimate even more recent than 6,000 BCE. The underlying assumption is that the global carrying capacity was similar between 10,000 BCE and 1900, absent the impact of significant fossil fuel use.

roughly the same as it was 10,000 years ago?

of people and animals, in total, stayed roughly the same from 10,000 BC to about 1700?

Once the natural carrying capacity of the planet fills up, it stays full. Before we began to use fossil fuels to enhance the planet's carrying capacity, the amount of animal life would have depended solely on the climate and the amount of photosynthesis going on. Overall I'd say those factors would have been approximately constant for that period. Once we began to use coal in a big way all bets were off.

I know this is wiki, so accuracy may be in question, but this page seems to be a sourced conglomeration of many different estimates of world population from about 10000 BCE to roughly the present day. While there's no doubt population has been rising at a dramatic rate since the industrial revolution, most estimates put world population somewhere between 1 and 10 million in 10000 BCE and around 600-700 million in 1700. While this isn't nearly the same rate as current growth, it's difficult for me to understand how this can be explained by the use of fossil fuels.

http://en.wikipedia.org/wiki/World_population_estimates

We hunted the wild animals out, used them as food, and appropriated their portion of the biosphere. The overall biomass probably didn't change too much as a result. We were replacements, not additions.

Which makes about as much sense as the 10,000 BC epoch.

What was the biomass at the start of the industrial age?

As was mentioned above, a bit more or less on the estimate in 10,000 BCE doesn't make a whiff of difference compared to what has happened since 1800.

I fear human selfishness will not allow such a logical solution to succeed.

If we wanted to turn things around, we would need to stop all fossil fuel use today, cut the world's population by over 50% well before the end of the century and cut the world's consumption of non-renewable resources by maybe 75% by then as well. That's just not going to happen, of course.

After 10 years of looking at this problem I'm convinced that it's not moral issues like selfishness or greed that are driving most our species' overgrowth behavior. I suspect it's something much deeper, related to how life evolves and the sorts of behavior that support the survival of organisms and species. Our behavior is motivated by positive feelings like, "I just want my kids to have a little better life than I did." When you get 7.3 billion people all thinking like that, and an industrial infrastructure that has learned how to make money by amplifying that desire, you get the situation we're in today. Even most of the people who are running that industrial infrastructure are operating from the same motive: "I just want my kids to have a little better life than I did."

No species on earth worries about the effect that its survival will have on other species or the biosphere. No species tries to control its own numbers. They simply try their best to survive. If they are too good or too lucky at survival, they enter overshoot. Because the system is finite, sooner or later their growth hits an external limit and their numbers get knocked down.

We are just another species.

No species on earth worries about the effect that its survival will have on other species or the biosphere. No species tries to control its own numbers. They simply try their best to survive.

I doubt any other species is thinking, "I just want my kids to have a little better life than I did." Maybe they do, but I'm guessing existence just is what it is.

We're now trying to take everything into account though. We want our kids to have a little better life than we did, but we're also trying to control our numbers, but we can't infringe too much upon personal choice, and we think about our effect on other species and the biosphere, but nobody wants to/can stop the resource concentration mechanism we call civilization from growing, even though the system in finite, but we're as successful as we are as a species because we constantly find ways around those limits, but not really because we have to keep coming up with ways to get around new limits, which we try to take into account, but it's difficult because everything we want is held up by those limits, etc, etc, etc.

All of which comes back around to our issue with death, which is central to the whole thing. We can't stop, but we can't continue.

I agree with every word of your post.

Breeders of humans are out of control, and have been for thousands of years. If you merely adjust your scale so it only goes back a maximum of 6K years, the message might better reach those you most need to reach.

Love it!