
Pearson eText Life in the Universe -- Instant Access (Pearson+)
4th Edition
ISBN: 9780135234457
Author: Jeffrey Bennett, Seth Shostak
Publisher: PEARSON+
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Chapter 6, Problem 19RQ
When did hominids arise, and when did modern humans arise?
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Chapter 6 Solutions
Pearson eText Life in the Universe -- Instant Access (Pearson+)
Ch. 6 - What are the three lines of fossil evidence that...Ch. 6 - How do studies of DNA sequences allow us to...Ch. 6 - Based on current evidence, what locations on Earth...Ch. 6 - What was the MillerUrey experiment, and how did it...Ch. 6 - What do we mean by an RNA world, and why do...Ch. 6 - Briefly summarize current ideas about the sequence...Ch. 6 - Briefly discuss the possibility that life migrated...Ch. 6 - Why do we think that evolution would have...Ch. 6 - Briefly discuss the early evolution of life, from...Ch. 6 - How do we think that eukaryotes evolved? What time...
Ch. 6 - What was the Cambrian explosion? Briefly discuss...Ch. 6 - How and when did life colonize land? Why did it...Ch. 6 - How do we know that the early Earth could not have...Ch. 6 - Summarize the history of the oxygen buildup as it...Ch. 6 - What was the KT impact, and how is it thought to...Ch. 6 - Briefly discuss the evidence for other mass...Ch. 6 - Discuss the threat that future impacts may pose to...Ch. 6 - Describe several adaptations that evolved so...Ch. 6 - When did hominids arise, and when did modern...Ch. 6 - Briefly describe and clarify a few common...Ch. 6 - Prob. 21RQCh. 6 - Briefly describe two main approaches to creating...Ch. 6 - We discover evidence of life, in the form of a...Ch. 6 - We discover an intact fossil of a eukaryotic cell,...Ch. 6 - We discover a preserved, 3.5-billion-year-old...Ch. 6 - We discover clear evidence that life arose on a...Ch. 6 - We discover a fossil of a large dinosaur that...Ch. 6 - We discover that, contrary to present belief,...Ch. 6 - We discover a crater from the impact of a...Ch. 6 - We discover an asteroid about 300 meters across...Ch. 6 - We find fossil remains of an early primate that...Ch. 6 - The first life created in the laboratory has an...Ch. 6 - The origin of life on Earth most likely occurred...Ch. 6 - The earliest living organisms probably were (a)...Ch. 6 - Prob. 35TYUCh. 6 - RNA world refers to (a) the possibility that life...Ch. 6 - Early life arose in an oxygen-free environment,...Ch. 6 - The oxygen in Earths atmosphere was originally...Ch. 6 - The Cambrian explosion refers to (a) a dramatic...Ch. 6 - Prob. 40TYUCh. 6 - The hypothesis that an impact killed the dinosaurs...Ch. 6 - According to the fossil evidence, modern humans...Ch. 6 - Origin of Life Studies. We cannot go back in time...Ch. 6 - A Brief History of Life on Earth. Take all the...Ch. 6 - Geology and Life. In Chapter 4, we discussed the...Ch. 6 - Prob. 48IFCh. 6 - Prob. 49IFCh. 6 - Impact Movie Review. Watch one of the Hollywood...Ch. 6 - Artificial Life Review. Numerous science fiction...Ch. 6 - Bacterial Evolution. Suppose that a mutation...Ch. 6 - Deep in Bacteria. In Cosmic Calculations 6.1, we...Ch. 6 - Prob. 54IFCh. 6 - Human Population Growth. During the twentieth...Ch. 6 - Impact Energy. Consider a comet about 2 kilometers...Ch. 6 - The Missing Link. As we discussed in this chapter,...Ch. 6 - Evolution by Choice. Consider the technology we...
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