BIOL 1201 Lecture : Biology Lecture 1
Document Summary
We do not have any evidence to suggest that life began anywhere else. A hypothesis- life began 4. 5 billion years ago (earth is 5 billion aprox) Hypothesis are based on observations, they are explanations for things that: people thought that new living things appeared all of the time. Spontaneous generation refuted: mid-1800s louis pasteur, pasteurized milk (heated to kill bacteria, boiling to kill germs, pasteur showed with broth boiling that spontaneous generation was not true and that microbes could be kill and kept away. Earth would not be the way it is today without life. Earth is about 4. 6 billion years old. Earth was aged using rocks from the moon that are intact because no circulation of magma: radiometric dating of meteors and moon rocks. Life arose about 3. 8 billion years ago: possibly when water became liquidized and cooled, chemical traces in rocks 3. 8 by, fossil bacteria in rocks 3. 5 by, no spontaneous generation now, but must have happened then.
