1493: Columbus created China's population boom and the Little Ice Age (book review)

I’ve found a fascinating new book along the lines of Guns, Germs, and Steel. This one called 1493: Uncovering the New World Columbus Created by Charles C. Mann.

For some insight into what it’s all about, here are some excerpts from the author.

Via the Bloomberg Presents Podcast


The Eastern and Western Hemispheres had been separated for 10s of millions of years, Pangaea. Columbus brought them together again causing an ecological convulsion, effectively creating Pangaea again.

On these European ships were passengers, beyond people, like plants, animals and micro-organisms. The most well-known were the diseases that wiped out some 90% of the population. Going the other way, you get foods, particularly the potato in Ireland.

Also, there is sweet potato and corn, particularly in China, where it has an equally large impact.

Columbus created China’s Population Boom

China, if you look at it on a map, one of the striking things is that it doesn’t have any big lakes or big bodies of water only these two major rivers, the Yellow and Yangtze. Other than that most of China is dry hills. So China has 20% of the world’s people and about 7% of the worlds fresh water.

Beyond that it gets even more out of whack because the main crop of China is rice which has to be grown in big fresh-water swimming pools. This creates a real tension and has been a major problem for every Chinese ruler to the present day.

In about 1600, corn and sweet potato come into China and they resulted in a huge harvest.  It was very, very productive and able to grown in dry land. Those dry hills turned into productive land and the Chinese fanned out into Western China to start planting corn and sweet potato.

The result was big boom in food supply, one historian put it at a 50% increase. As a result the population boomed and led to the crowded China that we know today.

The Little Ice Age – Global Cooling

When the native people died in massive numbers due to European diseases, they stopped impacting their environment. Doing things like burning fields, planting crops. All these open areas across both continents began filling in with trees. The result was that it drew carbon dioxide out of the air. An increasing number of studies show the carbon dioxide levels dropping with the arrival of Columbus.

This caused the Earth to get colder and caused what histories call the Little Ice Age.

Tobacco from the Amazon Ruined Native American Society

Jamestown was the first successful colony. All the ones before it had failed. They found a way to make it by taking a plant from the Amazon: Tobacco. They cleared a large part of the Chesapeake to plant it.

This was a radical transformation of the ecosystem which formerly had been a big patchwork of native american farms, fallow fields for medicinal plants, and other open and park-like woods which were burned every year to encourage fresh growth.

All of this was wiped out over a period of 10-20 years by the colonists to plant a monoculture of tobacco. This plant, which the colonists didn’t understand for a long time, has a unique capacity to suck the life out of the soil. An intensely resource hungry plant and when you harvest it nothing goes back into the soil.

As a result they devastated the soil in the area and made it harder and harder for the natives to make a living in their traditional way. This ecological change helped push the natives farther to the west.

Europeans brought Earthworms to North America

One of things I talk about in the book are the ecological changes that happened. In addition to the microbacterial onslaught and clear-cutting of the Chesapeake Bay, there was the introduction of the earthworm to Northern North America.c

As a result of the last ice age they were all smooshed by glaciers or frozen. There were some in the warmer parts of South America but they don’t have a lot of movement. If you have one in a 10 x 10 area they won’t leave that area in their lifetime. As a result the worms were very slowly moving their way north.

Places like the Chesapeake Bay didn’t have any earthworms and the entire ecosystem developed in their absence. The area didn’t have them moving the nutrients from the top of the soil and moving them to bottom, aerating the soil. As a result, plants evolved to get their nutrients from the top couple of inches.

When the earthworms came over with the Europeans they removed all the nutrients from that top area and moved it to the bottom. Causing another ecological change where the native plants and trees died off and other trees come in to replace them. This has been happening in Northern North America for last couple of hundred years.

Where I live in Massachusetts there are only a couple of worm free areas left. Places like Minnesota and Alberta still have a lot of worm free areas. In fact, ecologists and activists have this Quixotic anti-worm campaign with signs for fisherman like “don’t dump your worms” and “take them back with you like your trash.”

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