Week 5
Our Evolution Over the Past 4 Billion Years
Phylogenetic trees help identify the most fundamental features of the last universal common ancestor of all cellular life on Earth. How many domains of life are there? Maybe a viral phylogeny can be grafted as a root onto the tree of cellular life? Did viruses, viroids or ribozymes play a role in the origin of life? Was the RNA world a viral world? The controversial claim is made that there is no minimal amount of information or minimal size to “life”.
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08:20
5.1.1 The Last Universal Common Ancestor (LUCA)
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11:23
5.1.2 Are ET Bacteria Common?
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16:28
5.2.1 What Can Earth Life Tell Us About ET Life?
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10:34
5.2.2 How Many Domains of Life Are There?
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13:31
5.2.3 What Are Viruses? Are They Alive?
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16:55
5.2.4 Viruses and the Origin of Life
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11:25
5.2.5 Viroids
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10:20
5.2.6 Size and Life
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15:53
5.2.7 No Minimum Size
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20:13
5.3.1 Why did the Cambrian explosion happen so late?
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03:26
5.4.1 Charles Marshall: evolutionary biologist
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03:30
5.4.2 Tim Lenton: Earth systems scientist
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05:10
5.4.3 Simon Conway Morris: paleontologist
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08:26
5.4.4 Malcolm Walter: astrobiologist
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04:09
5.4.5 Joe Kirschvink: geobiologist
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26:29
5.5.1 Student Discussion
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06:31
5.5.2 Alien Misconceptions
Gaia: a new look at life on Earth
by James Lovelock, 1979, Oxford University Press
Revolutions that Made the Earth
by Tim Lenton and Andrew Watson, 2011, Oxford University Press