How many species are living around you right now? The answer may be larger than you think. Last week I was in the mountains of Greece with a group of biologists, and we challenged ourselves to answer this question. In two hours of walking around the forest, how many species could we find and positively identify?

The landscape, while beautiful, was heavily impacted by urban development and agriculture.

And the forests appeared to be not very diverse, with chestnut trees dominating the landscape.

Yet we surprised ourselves – with expert searchers like Miguel Araújo and Jon Fjeldså (shown here), we found over a hundred species we could positively name. Perhaps a fifth plants, a fifth fungi, two-fifths arthropods, and the rest birds and mammals. What appeared to be a very empty landscape held much diversity!

Here is one of our favorite finds – an interesting fungus that is certainly not recommended for eating!

So consider trying this game yourself – you may be surprised at how much diversity surrounds you, and perhaps also how many species you do not know. We probably found an equal number of species that were definitely different than others, but were mysteries to us.

Of course, diversity is higher in some parts of the world – generally the tropics have the most species (learn more here). Why this is the case is one of the great mysteries of ecology, and a subject for another much longer post…