I was talking to someone recently who told me that if we divided up the land between each living human, we would get a surprisingly small area each - of the order of two football fields. I was stunned. But not wanting to take someone’s word for it, I decided to check it out for myself.

The Earth is an oblate spheroid, which means it is a slightly squished ball. It is slightly fatter at its equator (6,378 km) than at its poles (6,357 km) due to its rotation. But, taking its mean radius of 6,371 km and assuming it is spherical, we get a surface area of 5.1 x 108 km2 using A=4πr2.

So it seems that the Earth is a big place. But remember that 71% of the Earth’s surface is water. So only 29% is land. So there is 1.479 x 108 km2 of land.

Some of this land is barren. Approximately 1/3rd of land is desert. This includes sandy deserts such as the Sahara, Gobi and Atacama as well as icy deserts such as Antarctica. So now we are down to 4.93 x 10 7 km2.

How many people are there on Earth? At the time of writing, the world population is estimated to be 7.6 billion and rising fast. It took humans over 200,000 years to hit 1 billion people and only another 200 years to hit 7 billion.

If we were to divide the useable land into plots of equal size and give a slice to each person, we would each get just under 6.5 km2. That about 2.5 x 2.5 km (about 1.5 x 1.5 miles).

To turn that into football pitches (assuming Association rules), that’s about 650 pitches give or take (turns out Association rules allow a range of pitch sizes).

So each person has a bit more that just two football fields. But still, this is a remarkably small area that has to sustain all life (plants and animals) that goes to feeding you. But it is not just yours alone. You will have to share it with one or two other apex predators - maybe a bear, lion, a wolf and an eagle. There will be several prey animals - a small herd of gazelle, a couple of buffalo and a smattering of rodents. There will be insects and other invertebrates.

Some of the land will be forest, some will be bog, some open plains. Not all will be suitable for all animals, resulting in each animal taking a small area based on its niche capabilities. You will have to fit in around this.

Everything you do must take into account the other animals living in the same 2.5 x 2.5 km square. If we were this aware about nature and the influence that our technology and population has on it, then we would take better care. We would be sensitive to the pesticides, emissions, human waste, energy consumption, deforestation and every other influence that our lives have on the plants and animals sharing the tiny plot of land with us.

So whatever you do in life, think about your small plot of land and the life you share it with.