Life by the Numbers | It's Okay to be Smart | PBS Digital Studios

There are now more than 7 billion human beings on Earth, and that got Joe Hanson wondering: How successful are we compared to other species? Joe takes a look at out how our numbers stack up to some other domains of life. It turns out that biomass, or what things weigh, can be more important than how many of something there are. Find out how our numbers stack up against everything from bugs to bacteria, and get ready for some mind-blowing numbers!

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