Lecture 6

Lecture 6 - The Origin and History of Life 2/14/11 History...

Info iconThis preview shows pages 1–13. Sign up to view the full content.

View Full Document Right Arrow Icon
2/14/11 The Origin and History of Life
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
2/14/11 History of life on earth 1) Before life began and the emergence of life 1) Some general patterns in earth’s history 1) Overview of geological timeline /
Background image of page 2
2/14/11 Before life began Universe came into existence 14 billion (14,000,000,000) years ago
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
2/14/11 Before life began Universe came into existence 14 billion (14,000,000,000) years ago Note: This is a really really really really really really really long time ago…
Background image of page 4
2/14/11 Before life began Universe came into existence 14 billion (14,000,000,000 years ago) The emergence of life Simplest living things were complex aggregations of molecules; left no fossil record and thus can only be studied theoretically and experimentally ‘Life’ is a difficult concept to define, but generally it is agreed that an assemblage of molecules is ‘alive’ if it can capture energy from the environment, and then use that energy to replicate itself, and thus be capable of evolving The most likely early replicators were short RNA- like molecules (“RNA world”)
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
2/14/11 History of life on earth 1) Before life began and the emergence of life 1) Some general patterns in earth’s history 1) Overview of geological timeline /
Background image of page 6
2/14/11 1) The distribution of land masses and oceans have changed over time, affecting the geographic distributions of organisms Some general patterns in the history of the
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
2/14/11 The distribution of land masses at several points in geological time
Background image of page 8
2/14/11 Continental drift and fossil distributions
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
2/14/11 1) The distribution of land masses and oceans have changed over time, affecting the geographic distributions of organisms 2) Catastrophic events have occurred… repeatedly. These include meteorite impacts, volcanic eruptions, massive changes in sea levels. Some general patterns in the history of the
Background image of page 10
2/14/11 Mass extinctions – catastrophic decline of species Invertebrate extinctions over the past 600 million years
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
1) The distribution of land masses and oceans have changed over time, affecting the geographic distributions of organisms 2) Catastrophic events have occurred… repeatedly. These include meteorite impacts, volcanic eruptions, massive changes in sea levels. 3)
Background image of page 12
Image of page 13
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 02/13/2011 for the course BIO 124 taught by Professor Dr.duran during the Winter '11 term at Drexel.

Page1 / 35

Lecture 6 - The Origin and History of Life 2/14/11 History...

This preview shows document pages 1 - 13. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online