Closed 10/26

Totaled 10/14 Mr F

Totaled 9/21 Mr F

Spon Gen and Sci Method

Spontainoius generation and the scietific method.  (Who did what) (What is the sci method and how was it applied)

2 Ideas on the origin of life (Spontaneous Generation):

abiogenesis: some life forms spontaneously arose from non-living matter.

heterogenesis: from  material you can get well-organized forms of life.

In the Colonial times, settlers believed that life came from life. For example, killing a cow and leaving it in a field to rot; maggots would come after several days. The settlers didnt realize that the meat attracted the maggots, and maggots weren't "born" from the meat. Scientists like Redi, Needham, Spallanazi, and Posteur proved various facts about spontaneous generation and life. Greek phiosopher Aristotle was one of the scientists that made observations that led to the idea of spontaneous generation 2300 years ago.  Based on what he saw, he reasoned that special "vital" forces caused some living things come into being from nonliving things. An example that the textbook gives for these beliefs is a recipe for bees written by a Roman poet 2000 years ago: "1. Kill a bull during the first thaw of winter. 2. Build a shed. 3. Place the dead bull on the branches and herbs inside the shed. 4. Wait for summer. The decaying body of the bull will produce bees."

STEPS IN THE SCIENTIFIC METHOD:

1. Observation
2. Question

   Summary. Like non living machines, living organisms must be engineered. That means

   planned, organized, coordinated, commanded and controlled. Living organisms are the most

   complicated objects in the universe so the requirement is mega-engineering, not the sub-idiot,

   headless, phantom, superstitious, engineering in the hallucinations of evolutionists.

    

    

3. Hypothesis
4. Predict
5. Testing

• Control group
• Experimental Group(s)
• Replication

    6. Conclusion 

To keep an experiment valid, it must consist of just one changed variable at a time. All others must be kept constant. This is call a controlled experiment. A theory is developed when an idea is tested thoroughly and an experiment is replicated enough times that it is widely accepted by the science community to be an accepted explaination. However, there are always people that question a theory and it is not considered to be the absolute truth.

Francesco Redi (Italian 1621-1697)

• Redi believed maggots developed from eggs laid by flies

He decided to test his theory by setting up an experiment.  He had three groups: meat in an open jar, meat in a jar covered with gauze and the last jar was completely sealed off.  In doing this experiment he realized that the meat had to be exposed to the outside world in order to create maggots.  He concluded this because the two meats exposed to air were covered with maggots, the one with no gauze actually had a swarm of flies.  This was in comparison to the sealed off container which had no maggots nor flies.

Spallanazi (10 January 1729 - 12 February 1799)

Spallanazi proved that air was needed for spontaneous generation by boiling and capping soup right away. After boiling for an hour and capping, the soup became sterile; and Spallanazi let no air into the pot, therefore no bacteria grew. His experiment proved that microbes traveled through air and could be killed.

http://www.kent.k12.wa.us/staff/TimLynch/sci_class/chap01/spallanzani.html

Above is a link for Spallanazi's experiment, step by step. Spallanazi proved Needham wrong, in that microbes travel through air and, as said below, can contaminate a solution.

Needham (1713-1781)

John Needam was an eighteenth century English naturalist.  He began studying natural science after learning about Leeuwenhoek's animacules.  He became a strong believer in spontaneous generation.  This being said, in 1745 Needham conducted an experiment in an effort to test whether or not microorganisms appeared spontaneously after boiling.  Needham's experiment consisted of boiling chicken broth, pouring the broth into a flask, and then sealing it.  Shortly after the broths cooled, they were filled with microorganisms, leading Needham to claim that organisms appeared through spontaneous generation.  Two years later, scientist Louis Pasteur proved that Needham's beliefs were wrong, because microorganisms are present in the air, and therefore contaminated his solution.

Louis Pasteur(1822-1895)

In 1864 the archetype scientist, Louis Pasteur (1822-1895), proved that the

microorganisms causing fermentation were airborne, not spontaneously generated as the evolution

vitalists insisted. Pasteur also provided reproducible evidence that the airborne distribution of

microorganisms is not uniform. Besides these undisputed experiments, Pasteur successfully

applied these findings to his work on vaccines for chicken cholera, anthrax and rabies. Yet in spite

of all this reproducible scientific evidence, and without one experiment to the contrary, the

evolution vitalists like Charles Darwin, as well as modern biology textbook authors, persisted in

propagandizing the ancient Greek spontaneous generation superstitions of 2,300 years earlier.

Figure 2. Pasteur’s experiments proved that microorganisms come from life, not non life.

In 1877, the physicist, John Tyndall (1820–1893), with an ingenious apparatus and

protocol proved most rigorously that life cannot arise from non life. His apparatus demonstrated

that light was invisible in a clean chamber and visible when dust with its invisible cargo of

bacteria was introduced. His protocol provided for the cycling of sterilizing heat which killed the

bacterial spores that hatched and became vulnerable after the first thermal stress. This settled the

issue for all time. Scientifically, vitalism and all of its evolution elaborations to “the many

different kinds of organisms living today, including you,” were disproven and relegated to the

dustbin of superstitions. These reproducible experiments have never been overturned and they

refute forever the superstitions of life coming from non life and endlessly evolving.

http://images.google.com/imgres?imgurl=http://www.josephmastropaolo.com/jmastrop/htdocs/images/meat.gif&imgrefurl=http://www.josephmastropaolo.com/data6.html&usg=__ZTbMkP3Y6lQA0-atOYwosaHos-8=&h=149&w=469&sz=13&hl=en&start=3&um=1&tbnid=8uZlu3KbvYtZTM:&tbnh=41&tbnw=128&prev=/images%3Fq%3Dredi%2Bexperiment%26hl%3Den%26sa%3DX%26um%3D1

     So I chose to add the two great videos because they go right along with what we covered in class on Friday regarding Spontaneous Generation and how it was proven to be false. The first video does a tremendous job of acting out the some of the experiments we learned about. It also deals with how Spontaneous generation came to be an accpeted idea and then how it faded. The second video does a great job of showing how Spontaneous Generation was dispoved by Pasteur's flask experiment. I found this to be a good addition to the helpful figure above.

     In the 19th century, It was common belief that smaller organisms arose spontaneously from organic matter. People relied on what they saw, and did not question the science and the reasoning that could be behind it. For example, people knew that larger organisms reproduced sexually because it was something that they could see when they were raising animals. Before the invention of the microscope, it was impossible to see how smaller organisms, like insects and microorganisms reproduced. People assumed from what they saw that when larger animals died, they decomposed into smaller organisms like maggots and flies.