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

Cats

We may be surprised at how seemingly small decisions can make for a big impact. Pets are an excellent example. A pet is an animal kept for companionship or pleasure. They serve no purpose other than to help make us happy.

Apparently we need lots of joy. For example, we are enjoying an estimated 200 million to over 1 billion domesticated cats. Chances are good that you’ve encountered domestic cats so we won’t describe them. But do you know their effect? For one, a typical cat needs 250 to 300 food calories a day. Taking this as an average and assuming a median number of cats then these carnivores take about 2.5e+17 Joules of energy each year. That’s a lot of energy.

Also, while cats reportedly originated in Egypt, we’ve placed them everywhere except the Antarctic. And we’ve let some of them run wild. Thus, in the U.S. alone they are responsible for the deaths of about 2 billion birds and 15 billion small mammals annually; including the extinction of some.

Small decisions, such as having a pet, can lead to big consequences. A consequence of having cats as pets has led to them getting a much larger share of (autotrophic) energy than they would have naturally obtained. And through extinctions, they’ve eliminated future competition for this energy. How will other small decisions be affecting our future?

Feral Cat – Unsplash

The Petrol Station

For the privileged few, there’s nothing more carefree than driving along on a big, empty, wide open highway. You aim for the horizon and you’re not too worried about whether you get there or not. Roll down the window, let the breeze blow through your hair and relax as all your worries disappear.

Relax until the dashboard displays a light that you’ve never seen before. It can’t be, it’s the big red Low Fuel warning light. It pulsates steadily. Dimming a little as the sun shines on it then brightening as the dashboard re-enters the shade. With it, somehow the horizon becomes much less inviting and a petrol station, any petrol station, would be gratefully discovered. The petrol station, an oasis from which to fill the car’s tank and perhaps add a bit more to your own tank, your stomach. But the map display on the dashboard shows you that the closest petrol station is a few hundred kilometres away. Your drive is no longer worry free.

While the above is a simple little bit of fiction, it is analogous to humans on Earth. We’re driving along a technological and cultural highway. But where the car in the story consumes the same rate of petrol, humans are consuming more fuel and faster. Each and every day. There are more humans. And each of them want more and better services. We can change our story to reflect this. The change is that once the Low Fuel Warning light appears then you accelerate, which of course burns fuel at a greater rate. But this higher rate doesn’t get you any greater a chance of reaching the petrol station.

One option is to lighten the load in the car. This will allow the driver to go further, would it be far enough? An analogy to this is reflected by the recent UN report stating that over 1 million species are nearing extinction due to humankind.  That’s one eighth of the total. Without those creatures then there’s more energy available for humans. Ever wonder what the Earth will be like once those creatures are gone? Ever wonder if driving a car aimlessly down a highway is truly carefree?

La Fleur