I gave one of my first-year university lectures today, on biodiversity and extinction rates, in which I mention the recent population growth of the Earth's most abundant large animal species ever: us.

I still remain completely gobsmacked by the magnitude of the world's recent human population growth.

8.27 billion: today's population, according to worldometers.info.

7.2 billion: in 2015 when I started teaching the course.

6.8 billion: in 2008 when my daughter was born.

3.8 billion: in 1971 when I was born.

2.3 billion: in 1946 when my parents were born.

1.9 billion: in 1923 when my Dad’s Dad was born.

So 1.9 billion to 8.2 billion in just over a century!

I worry about whether we can sustain this many people on the planet long-term while retaining and restoring a thriving wild biosphere that supports us.

Some of us are going to have to learn to use a lot less energy and resources.

#SoManyPeople #HumanPopulation