When the mariner was about twelve, he was reading one of his father’s textbooks that had a chapter on Thomas Malthus, a British economist who, in 1798, said that population growth would be destructive and would be the end of the human species. Being impressionable at that age, the mariner never forgot that warning. He has not thought about Malthus for a while but has always been aware of the impact of overcrowding on the earth in general and on the human race in particular.

Malthus based his prediction on the fact that population was a geometric growth pattern (1,2,4,8,16..…) and food sources grew arithmetically (1,2,3,4,5…..). Eventually, he reasoned, people would die of starvation. Among several opinions about how to control human population, the most memorable was to increase the death rate. Little did he know that science would not shorten lives but would extend them; now, on the horizon, people will live greatly prolonged lives. Further, science would boost food production to keep up with population growth.

All this came back to mind when Elizabeth Kolbert was interviewed on television. She is the author of a new book titled The Sixth Extinction, An Unnatural History. (Henry Holt & Company). Readers may be able to watch the interview on Jon Stuart’s webpage, http://www.thedailyshow.com/videos

The title derives from the fact that five great extinctions have occurred in the history of living things on Planet Earth. Most know about a meteorite that hit Earth in Mexico and ended the era of dinosaurs. Check Wikipedia or search “five great extinctions” for more information. Kolbert portends that humans are the cause of the sixth great extinction.

The book is drawn from scientific research and trips around the world with experts on climate, oceanography, ecology, animal and plant specialists and others who study living things and their habitats.

To make a detailed analysis brief, Kolbert’s point is that our species once existed only on the plains of Africa and now has spread to every spot on Earth, that is, every habitat of every plant, animal, fish, invertebrate, bacteria, and has altered every single ecosystem. The result of this overpopulation, especially by a species that is extremely high maintenance in its use of food, space, materials and energy, is that tens of thousands of species are falling into extinction on a continuous basis.

Not only are there so many humans that other species are crowded out (cities and sensitive estuaries filled in for the benefit of real estate development to name two), humans are a dirty and careless bunch. Humans are the cause of innumerable destructions of habitat by deliberately invading them (farming and river dams to name just two). Humans carry diseases that kill not only humans but other plant and animal life as well, spew chemical damage into every habitat on Earth, and alter climates to such a massive degree that animals from whales and polar bears to tiny fish, bees, coral species and plant life over the entire Earth are dying or being deliberately killed.