Category: Life and Climate
LC5C. Stay Current—The Origin of Our Oxygen-Rich Atmosphere
Stay current for chapter 5 { Life and Climate Contents } 2021-09-03. Longer Days Likely Boosted Earth’s Early Oxygen. Source: By Damond Benningfield, Eos/AGU. Excerpt: Microbial mats in a Lake Huron sinkhole, combined with modeling work, suggest that the changing length of Earth’s day could have played a key role in oxygenating the atmosphere.… [https://eos.org/articles/longer-days-likely-boosted-earths-early-oxygen] […]
LC4C. Stay Current—The Beginning of Life on Earth
Stay current for chapter 4 { Life and Climate Contents } 2024-04-30. Ancient crystals suggest early Earth had land and freshwater. By ELISE CUTTS, Science. Excerpt: Hardy zircon minerals found in Australian rocks suggest conditions for life existed 4 billion years ago …“We found evidence for two things: There was land above sea level and, […]
LC3C. Stay Current—How Do Scientists Play the Dating Game?
Stay current for chapter 3 { Life and Climate Contents } 2009 June 7. Early rocks to reveal their ages. By Jennifer Carpenter, BBC News. Excerpt: A new technique has been helping scientists piece together how the Earth’s continents were arranged 2.5 billion years ago. The novel method allows scientists to recover rare minerals from rocks. By […]
LC2C. Stay Current—Where Does Earth’s Atmosphere Come From?
Staying current with chapter 2 { Life and Climate Contents } 2016-05-09. Earth’s ancient atmosphere was half as thick as it is today. By Roland Pease, Science. Excerpt: …very little is known about how thick Earth’s ancient atmosphere once was. Now, a new study suggests that Earth’s atmosphere 2.7 billion years ago was between a quarter to […]
LC13. What Does Earth’s Past Tell Us About Our Future?
Chapter 13 { Life and Climate Contents } In Life and Climate we have seen how Earth’s changing climate and evolving life forms have influenced each other over the past 4.6 billion years of our planet’s history. In the first part of this chapter we briefly review highlights of this fascinating story. In the last […]
LC12. Climate and Culture
Chapter 12 { Life and Climate Contents } I. New Ways of Living and Thinking Although anatomically modern human beings had evolved by 100,000 years ago, there is little evidence that they lived and behaved differently from Homo erectus. However, evidence shows that major changes were beginning to get under way about 50,000 years ago. […]
LC11. Climate and Human Evolution
Chapter 11 { Life and Climate Contents } Paleoanthropologists—scientists who study the physical evolution of humans—call our species Homo sapiens. This means that we are part of a category of individuals who share common characteristics, the genus Homo, and that within that genus our group or species is called “sapiens.” Fossil evidence shows that there […]
LC10. The Ice Ages
Chapter 10 { Life and Climate Contents } I. The Climate Record During the Cretaceous period, the dinosaurs enjoyed a climate much warmer than we have today; however, other periods were much colder than it is now. In recent years paleoclimatologists (scientists who study past climates during the Earth’s history) have gathered evidence of ice […]
LC9. What Happened To the Dinosaurs?
Chapter 9 { Life and Climate Contents } For about 150 million years dinosaurs were the dominant animal life on our planet. Then, 65 million years ago, dinosaurs became extinct. That was bad news for the dinosaurs but good news for the small mammals that managed to survive. Since they no longer had to compete […]
LC8.1. Dissolving Rocks
{ Life and Climate Contents } { All GSS Books } In the laboratory, you can simulate the process of chemical weathering by setting up an arrangement as shown here. This apparatus will allow you to control drops of soda water (carbonic acid, H2CO3) to drip onto limestone (CaCO3) for a few days, and collect […]