Visit http://TED.com to get our entire library of TED Talks, transcripts, translations, personalized talk recommendations and more.

The common thinking on biological sex goes like this: females have two X chromosomes in their cells, while males have one X and one Y. In this myth-busting talk, science writer and podcaster Molly Webster shows why the so-called “sex chromosomes” are more complicated than this simple definition — and reveals why we should think about them differently.

The TED Talks channel features the best talks and performances from the TED Conference, where the world’s leading thinkers and doers give the talk of their lives in 18 minutes (or less). Look for talks on Technology, Entertainment and Design — plus science, business, global issues, the arts and more. You’re welcome to link to or embed these videos, forward them to others and share these ideas with people you know. For more information on using TED for commercial purposes (e.g. employee learning, in a film or online course), submit a Media Request here: http://media-requests.TED.com