Social media promises us an ever-expanding circle of friends, but that may be an empty promise. Social behavior is firmly rooted in biology, and our brains are hard-wired to maintain meaningful relationships with no more than around 150 people.

In an SFI Community Lecture on March 12 in Santa Fe, evolutionary psychologist Robin Dunbar explored how our brains have evolved to support the complex social structures that ensure our survival, and how the sizes of our social groups are defined by our DNA. Dunbar's research suggests real limits not only to our personal relationships, but to the size and capacity of every community in which we participate -- Facebook “friends” and Twitter “followers” included.

Watch Dunbar's lecture (77 minutes, March 12, 2014)

Hear Dunbar's interview on the Santa Fe Radio Cafe (March 12, 2014)

Read the Santa Fe New Mexican's preview of the lecture (March 11, 2014)

Read the Albuquerque Journal North's preview of the lecture (March 7, 2014)

Dunbar is director of the Social and Evolutionary Neuroscience Research Group, Department of Experimental Psychology, University of Oxford.

SFI Community Lectures are broadcast live online. To watch a lecture as it happens, visit SFI's YouTube page. You can participate in the live Twitter discussion at #sfi_live or @sfi_live.

SFI’s 2014 Community Lectures are made possible through the generous support of Thornburg Investment Management.

For a complete listing of upcoming community events, please check here.

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