1.7 billion Tyrannosaurus rexes walked the Earth before going extinct, new study estimates

Global warming will likely cross dangerous 1.5 C threshold within 5 years, UN report warns | Modern humans arose after 2 distinct groups in Africa mated over tens of thousands of years | Yellowstone volcano super-eruptions appear to involve multiple explosive events Created for {EMAIL} | [Web Version]( May 18, 2023 CONNECT WITH LIVESCIENCE  [Facebook]( [Twitter](  [LIVESCIENCE]( Amazing science every day [SIGN UP]( ⋅ [WEBSITE](  [] Top Science News [] [1.7 billion Tyrannosaurus rexes walked the Earth before going extinct, new study estimates]( (Shutterstock) [1.7 billion Tyrannosaurus rexes walked the Earth before going extinct, new study estimates]( The new prediction suggests fewer T. rex individuals roamed our planet than scientists previously thought. [Read More]( [] Climate Change [] [Global warming will likely cross dangerous 1.5 C threshold within 5 years, UN report warns]( (Joaquin Meabe/Getty Images) [Global warming will likely cross dangerous 1.5 C threshold within 5 years, UN report warns]( The U.N. weather agency has warned that El Niño and human-caused climate change will likely push temperatures into "uncharted territory." [Read More]( [] History & Archaeology [] [Modern humans arose after 2 distinct groups in Africa mated over tens of thousands of years]( (Ariadne Van Zandbergen via Alamy Stock Photo) [Modern humans arose after 2 distinct groups in Africa mated over tens of thousands of years]( Modern humans arose after a complex history of intermingling between ancestors on at least two different but closely related evolutionary branches, a new study suggests. [Read More]( [] Planet Earth [] [Yellowstone volcano super-eruptions appear to involve multiple explosive events]( (Holger Leue/Getty Images) [Yellowstone volcano super-eruptions appear to involve multiple explosive events]( The last caldera-forming eruption at Yellowstone "was much more complex than previously thought," according to the annual report about activity at the supervolcano. [Read More]( [] Astronomy & Astrophysics [] [Some black holes may actually be tangles in the fabric of space-time, new research suggests]( (ESA/ATG medialab) [Some black holes may actually be tangles in the fabric of space-time, new research suggests]( A new paper discusses how light interacts with theoretical objects called "topological solitons" — kinks in the fabric of space-time that look just like black holes. [Read More]( [] Health [] [Mpox could surge again this summer, CDC warns doctors]( (Paul Bersebach/MediaNews Group/Orange County Register via Getty Images) [Mpox could surge again this summer, CDC warns doctors]( The United States could see a resurgence of mpox in the coming months, on the heels of spring and summer gatherings, the CDC warns. [Read More]( [] [What are the heaviest organs in the human body?]( (NOAH SEELAM / Contributor via Getty Images) [What are the heaviest organs in the human body?]( Organs come in all shapes and sizes to reflect the myriad of important functions they perform. But which of the body's organs weigh the most? [Read More]( [] Daily Quiz [] In the past, how many T. rexes did scientists think existed on Earth? (Find the answer [here]() [Vote]( [400 million]( [Vote]( [Around 1 billion]( [Vote]( [2.5 billion]( [Vote]( [8 billion](   [Sign Up]( | [Update Profile]( | [Unsubscribe]( [Privacy Policy]( | [Cookies Policy]( | [Terms and Conditions]( CONTACT US: [FEEDBACK](mailto:livescience@smartbrief.com) | [ADVERTISE]( Future US LLC © Full 7th Floor, 130 West 42nd Street, New York, NY, 10036