The Pyramid of Life

We dominate the animal kingdom. We are the apex predator on Earth. We control, eradicate, or nurture others, whether as large as a mammoth or small as bacteria.

The trophic pyramid is an illustrative segregation of Earth’s life into 4 levels. A lower level provides energy and nutrients to the higher level. Level 1, the lowest, includes all the autotrophs or plants. Level 2 has herbivores. Level 3 has carnivores. Level 4, the apex, contains the omnivores that consume almost anything. Most people live at Level 4 of the pyramid.

Assume everyone lives at Level 4. People require 12,500 Joules per day. As a rough metric, the ecological efficiency is 10% meaning that only a tenth from a lower level gets transferred to the higher level. Thus, 3.65e+19 Joules of energy from Level 1 supports the 8.012 billion people alive today. On average, Level 1 life annually stores about 2.3e7 Joules per sq.m. of energy. Thus, overall, we annually consume about 32% of energy that is captured by Level 1 life.

Being at the apex and in full control, we can form a future of our choice. So far, people have co-opted more than half the land surface for agriculture to support this consumption. We and our livestock outweigh all other wildlife 24 fold resulting in another mass extinction event. Our future could include wildlife or it will only include living creatures that directly support and maintain the human population? Which do you want and what will you do to achieve it?
Polar_Bear

Wildfires

The human control of fire is often mentioned as the progenitor to civilization. Fire, as we’ve already noted, is the chemical release of energy. Typically it requires three things; fuel, oxygen and an ignition source. When these combine then there’s a release of energy. Wilderness fires are natural and can lead to a huge, acute release of energy. Humans changed this to a slow, chronic, controlled release such as when we chop wood and burn it in a wood stove. And our civilizations thus prospered with this skill.

The current firestorm in Australia vividly demonstrates the natural release that wild bush fires can engender. At least 11 million hectares have released their latent energy stores(about 2.4e19 Joules); that is, the fires have burnt all the plants. The plants are the primary producers as shown in the trophic pyramid. Current estimates arrive at over 480 million primary, secondary and tertiary consumers of the pyramid as being affected by the fire and will likely die. They will starve due to the fire burning all the primary producers.

Consider the consequence. An area about the size of New York state has just lost all its stores of energy. Lack of water means that regrowth may be long in coming or may never come. What does this mean for the future? As more and more regions of the Earth’s surface become barren then there is less for all consumers of the trophic pyramid, including humans. Thus, as the human population continues to grow, they will have less stores of energy from which to draw. And the Earth will have a simpler and simpler ecosystem. Is this the goal of civilization? Can our civilization continue to exist without fire?

Bushfire January 2020
Australia – Bushfire