--- title: Google Doodle Honors 'XY' Genetics Pioneer Nettie Stevens description: Her discovery that X and Y chromosomes combine to determine gender was an immense contribution to the field of genetics. canonical: https://time.com/4396045/google-doodle-nettie-stevens/ author: TIME Staff article:opinion: false article:content_tier: free article:published_time: 2016-07-07T04:26:20.000Z article:modified_time: 2026-04-13T07:34:09.339Z og:title: New Google Doodle Honors Genetics Pioneer Nettie Stevens og:description: Her XY chromosome discovery was a watershed in genetics og:url: https://time.com/4396045/google-doodle-nettie-stevens/ og:site_name: TIME og:image: https://static.time.com/v3/assets/bltea6093859af6183b/blt9bfb2dbe6c080764/69889af0bc6cfc317e3ddb3c/screen-shot-2016-07-07-at-11-54-38-am.png?branch=production&width=514&quality=75&auto=webp&crop=16:9 og:image:width: 514 og:image:height: 289 og:image:alt: Screen Shot 2016-07-07 at 11.54.38 AM og:type: article twitter:card: summary_large_image twitter:title: New Google Doodle Honors Genetics Pioneer Nettie Stevens twitter:description: Her XY chromosome discovery was a watershed in genetics twitter:image: https://static.time.com/v3/assets/bltea6093859af6183b/blt9bfb2dbe6c080764/69889af0bc6cfc317e3ddb3c/screen-shot-2016-07-07-at-11-54-38-am.png?branch=production&width=514&quality=75&auto=webp&crop=16:9 ---  # A New Google Doodle Celebrates Genetics Pioneer Nettie Stevens by [TIME Staff](https://time.com/author/time-staff/) ## TIME Staff Jul 7, 2016 4:26 AM UTC  Google Doodle for Nettie Stevens' 155th Birthday. Google Doodle for Nettie Stevens' 155th Birthday.Google by [TIME Staff](https://time.com/author/time-staff/) ## TIME Staff Jul 7, 2016 4:26 AM UTC That X and Y chromosomes combine to determine gender, now common knowledge taught in biology classes the world over, was discovered by pioneering American scientist [Nettie Stevens](https://www.google.com/doodles/nettie-stevens-155th-birthday). On what would have been her 155th birthday, Google is celebrating her immense contribution to the field of genetics with a Doodle. Stevens was born in Cavendish, Vt. in 1861, and grew up in an era where job opportunities for women were severely restricted. After studying at Stanford University, she got her PhD at Bryn Mawr College, where she did the bulk of the research that led to her breakthrough. Stevens died of breast cancer in 1912, but, as Google [said](https://www.google.com/doodles/nettie-stevens-155th-birthday), “her discovery lives on.” ```json [{"@context":"https://schema.org","@type":"NewsArticle","@id":"https://time.com/4396045/google-doodle-nettie-stevens/","mainEntityOfPage":{"@type":"WebPage","@id":"https://time.com/4396045/google-doodle-nettie-stevens/"},"headline":"A New Google Doodle Celebrates Genetics Pioneer Nettie Stevens","datePublished":"2016-07-07T04:26:20.000Z","dateModified":"2026-04-13T07:34:09.339Z","description":"Her discovery of the XY chromosome system was a watershed moment in genetics","url":"https://time.com/4396045/google-doodle-nettie-stevens/","keywords":["Newsfeed","Genetics","Biology","Google Doodle","Discovery","Stanford"],"thumbnailUrl":"https://static.time.com/v3/assets/bltea6093859af6183b/blt9bfb2dbe6c080764/69889af0bc6cfc317e3ddb3c/screen-shot-2016-07-07-at-11-54-38-am.png?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","author":[{"@type":"Person","name":"TIME Staff","jobTitle":null,"url":"https://time.com/author/time-staff/"}],"articleSection":"","image":[{"@type":"ImageObject","url":"https://static.time.com/v3/assets/bltea6093859af6183b/blt9bfb2dbe6c080764/69889af0bc6cfc317e3ddb3c/screen-shot-2016-07-07-at-11-54-38-am.png?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","width":1200,"height":675,"headline":"Screen Shot 2016-07-07 at 11.54.38 AM","caption":"Nettie Stevens Google Doodle","creditText":"Google","representativeOfPage":true}],"publisher":{"@type":"Organization","name":"Time","url":"https://time.com/","logo":{"@type":"ImageObject","url":"https://time.com/images/logo.png","width":528,"height":156},"foundingDate":"March 3, 1923","sameAs":["https://www.facebook.com/time","https://www.instagram.com/time/?hl=en","https://twitter.com/time","https://www.pinterest.com/timemagazine"]}},{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"/tag/time-section-newsfeed/","name":"Newsfeed"}},{"@type":"ListItem","position":2,"item":{"@id":"https://time.com/4396045/google-doodle-nettie-stevens/","name":"A New Google Doodle Celebrates Genetics Pioneer Nettie Stevens"}}]}] ```