A butterfly hovering near a flower The butterfly effect is the concept that small changes can lead to largely altered outcomes, making the future vastly difficult to predict. (more) butterfly effect chaos theory Actions Share Share Share to social media Facebook X URL https://www.britannica.com/science/butterfly-effect Share Share Share to social media Facebook X URL https://www.britannica.com/science/butterfly-effect Written by Allison Rauch Allison...

　　 　　The Confessions of Nat Turner Title page of 1832 version of The Confessions of Nat Turner, an account of a slave rebellion, as told to and published by Thomas R. Gray. The work was first published in 1831. (more) The Confessions of Nat Turner work by Nat Turner, primary source Actions Share Share Share to social media Facebook X...

　　 　　The Dakota One of the first apartment buildings constructed in the sparsely populated Upper West Side when it was completed in 1884, the Dakota played a notable role in the transition of New York City's elites from living in single-family homes to luxury apartment buildings. (more) the Dakota building, New York City, New York, United States Actions Share Share...

　　 　　Sarah Paulson American actress Sarah Paulson at the 77th annual Tony Awards at the David H. Koch Theater at Lincoln Center for the Performing Arts, New York City, June 16, 2024. (more) Sarah Paulson American actress Actions Share Share Share to social media Facebook X URL https://www.britannica.com/biography/Sarah-Paulson Share Share Share to social media Facebook X URL https://www.britannica.com/biography/Sarah-Paulson Also known...

　　 　　Measuring race Scientists of the 18th and 19th centuries sought to categorize and measure different races. Measurements of the cranium were especially important in their now-debunked hierarchies of human groups. (more) scientific racism racism Actions Share Share Share to social media Facebook X URL https://www.britannica.com/topic/scientific-racism Share Share Share to social media Facebook X URL https://www.britannica.com/topic/scientific-racism Written by Audrey Smedley...

　　 　　Anura Kumara Dissanayake The leader of the leftist Janatha Vimukthi Peramuna party, outsider candidate Anura Kumara Dissanayake won Sri Lanka's 2024 presidential election, reflecting public frustration with the traditional political elite. (more) Anura Kumara Dissanayake president of Sri Lanka Actions Share Share Share to social media Facebook X URL https://www.britannica.com/biography/Anura-Kumara-Dissanayake Share Share Share to social media Facebook X URL...

　　 　　Liz Phair American singer-songwriter and guitarist Liz Phair, 1994. (more) Liz Phair American singer-songwriter Actions Share Share Share to social media Facebook X URL https://www.britannica.com/biography/Liz-Phair Share Share Share to social media Facebook X URL https://www.britannica.com/biography/Liz-Phair Also known as: Elizabeth Clark Phair Written by Laura Payne Laura Payne is a freelance writer whose work covers many topics. She is a...

　　 　　With longevity increasing and retirees wondering if they’ll outlive their nest eggs, some employees are starting to side-eye their 401(k) plans. A 401(k) is a defined contribution plan, meaning the onus is on you to determine how much to put into it and how to invest it, with no guarantee you’ll save enough to last throughout retirement. 　　It’s no...

　　gender-affirming hormone therapy medicine Actions Share Share Share to social media Facebook X URL https://www.britannica.com/science/gender-affirming-hormone-therapy Share Share Share to social media Facebook X URL https://www.britannica.com/science/gender-affirming-hormone-therapy Written by Kara Rogers Kara Rogers is the senior editor of biomedical sciences at Encyclopædia Britannica, where she oversees a range of content from medicine and genetics to microorganisms. She joined Britannica in 2006 and......

　　Project Blue Book United States Air Force program Actions Share Share Share to social media Facebook X URL https://www.britannica.com/topic/Project-Blue-Book Share Share Share to social media Facebook X URL https://www.britannica.com/topic/Project-Blue-Book Written by Michele Metych Michele has a B.A. in English from Southeast Missouri State University and an M.A. from DePaul University. She's a Chicago girl at heart, but she still misses...

　　 　　Challenger Deep Swiss oceanographer Jacques Piccard (back) and U.S. Navy officer Don Walsh making their descent to the Challenger Deep aboard the bathyscaphe Trieste in 1960. (more) Challenger Deep submarine feature, Pacific Ocean Actions Share Share Share to social media Facebook X URL https://www.britannica.com/place/Challenger-Deep Share Share Share to social media Facebook X URL https://www.britannica.com/place/Challenger-Deep Written by Michelle Castro Michelle...

　　 　　Warbonnet Chief Joseph, a leader of the Nez Percé, wearing his warbonnet in a portrait by photographer Edward Curtis, in 1903. (more) warbonnet headdress Actions Share Share Share to social media Facebook X URL https://www.britannica.com/topic/war-bonnet Share Share Share to social media Facebook X URL https://www.britannica.com/topic/war-bonnet Written by Adam Volle Adam Volle is a freelance writer and editor based in...