How many different species are on earth?

If mankind were to visit Mars and find life, among our first questions would be how many different forms of it exist there. Ironically though, this is not a question that we can answer about our own planet.

 

On earth, life is on the bottoms of the ocean, it is floating on the dust in the atmosphere, and it is found in every crevice in between. Try as we might, it is nearly impossible to count all the species. But so far, we have cataloged over 1,600,000 of them. And we can only estimate how many are yet to be  found and identified.

 

Back in 2011, a group of scientists actually did produce such an estimation. Their approach to doing this was a bit like estimating the number of jellybeans in a jar based on how many are visible, and doing so for each color. Except with way more sophisticated math.

Based on the number of known species cataloged at the time, they came up with the estimate of 8,749,900 species, not counting the microbes (bacteria and archaea).

 

If we were to break this number down into the classification groups (plants, animals, etc.), it would look like this graphic below. It’s mostly animals, which includes all insects, spiders, and other crawly things.

 

Now, let's talk about the microbes - all the creatures we can't see. In May 2016, a couple of other researchers came up with a new estimation for those guys: 100,000,000,000 species (or, 100 billion). And this is the low end of their estimation*. 

 

To put this in perspective, here’s how that number compares to the 8,749,900 forms of higher life shown above (eukaryotes).

 

You can see how the number of more complex species is almost insignificant.

 

This amount of microbial diversity is incomprehensible. To me, it seems impossibly high. But how would I know? I can’t see all the microbes around me (and inside me). That is part of what makes this a tough estimation to make. The other part is that at the microbial level, it is difficult to distinguish one species from another when you are trying to classify them. A given species of bacteria will usually have many different strains, and it’s a fuzzy genetic line sometimes that separates a 'strain' from a 'species'. Microorganisms are indifferent to our attempts to classify them. They just are what they are, and they are evolving.

 

In any case, consider that as human beings, we are only one of billions of species on a planet where "life finds a way". Lots of ways. In a universe that is otherwise sterile for as far as we can see, we should be humbled by the diversity of life that surrounds us. If we protect life in all of its forms, there is still much we can learn from it.

*I used the lower end of the estimation because it included microscopic fungi, which were also included in the 8,749,900 value. The upper estimation was 10-fold higher: 1 trillion.

 

 

 

 

 

Evolution From Blog to Website

For the scientist, the process of peer-reviewed publication forms the foundation for all research. It is a feedback loop - a self-perpetuating and co-dependent exchange of input and output between scientists.

There was a nice piece written a few years ago in Wired magazine about the power of feedback loops. That article explains that all feedback loops have four components: 

1. Evidence

2. Relevance

3. Consequence

4. Action

In regards to science, Evidence = Data.

But raw data alone won't persuade the majority of your audience. From the Wired article:  

"..the information must be relayed to the individual, not in the raw-data form in which it was captured, but in a context that makes it emotionally resonant. This is the relevance stage."

In other words, relevance is a function of how well you are able to communicate your data.

Communicating science to the general public is a notorious challenge for most scientists. But communication even among scientists can be a challenge too. In part, because most scientists today work across disciplines.

In either case, few things can be as helpful to the process as a clear diagram that distills and translates the cognitive beauty of really good data into something that is equally pleasing aesthetically. Since I enjoy producing diagrams, I recently decided to expand this blog into a website (www.cognitivefeedbackloop.com), and offer up my services to other scientists. 

For a nominal fee, I will gladly draw up a publication quality vector diagram according to publisher specifications for any scientist that is interested. I will continue with the blog too, which will also now serve as a gallery for some of my past work (albeit with a different intended audience in mind).

Good science communication with the public feeds back to the researcher in the form of continued funding support for further work. And good science communication within the scientific community feeds back to the researcher in the form of new discoveries, that enable deeper questions to be explored. 

In either case, I believe that a beautiful diagram will reach far more people than data or text can on its own. If you are a scientist, and you think I might be able to help you out in this regard, let's chat. Send me an email through robert@cognitivefeedbackloop.com