Mitochondrial Eve

According to Wikipedia:

"In the field of human genetics, Mitochondrial Eve refers to the matrilineal most recent common ancestor (MRCA) of modern humans. In other words, she was the woman from whom all living humans today descend, on their mother's side, and through the mothers of those mothers and so on, back until all lines converge on one person. Because all mitochondrial DNA (mtDNA) is generally passed from mother to offspring without recombination, all mitochondrial DNA (mtDNA) in every living person is directly descended from hers by definition. Mitochondrial Eve is the female counterpart of Y-chromosomal Adam, the patrilineal most recent common ancestor, although they lived thousands of years apart.

Each ancestor (of people now living) in the line back to the matrilineal MRCA had female contemporaries such as sisters, female cousins, etc. and some of these female contemporaries may have descendants living now (with one or more males in their descendancy line). But none of the female contemporaries of the "Mitochondrial Eve" has descendants living now in an unbroken female line.

Mitochondrial Eve is estimated to have lived around 200,000 years ago,^[2] most likely in East Africa,^[3] when Homo sapiens sapiens (anatomically modern humans) were developing as a population distinct from other human sub-species.

Mitochondrial Eve lived later than Homo heidelbergensis and the emergence of Homo neanderthalensis, but earlier than the out of Africa migration.^[4] The dating for 'Eve' was a blow to the multiregional hypothesis, and a boost to the hypothesis that modern humans originated relatively recently in Africa and spread from there, replacing more "archaic" human populations such as Neanderthals. As a result, the latter hypothesis became dominant."

(http://en.wikipedia.org/wiki/Mitochondrial_Eve)

Imagine - we all came from Mitochondrial Eve:

 

Animal Testing

I am personally against the use of animal testing for cosmetic purposes. I found a website that clearly outlines strong arguments against the practice. I wish to echo the sentiments of this excerpt:

"Arguments against:

• Cosmetics testing on animals is not required by govts In Defense of Animals. - "These [cosmetic] companies claim they test on animals to establish the safety of their products and ingredients for consumers. However, the Food and Drug Administration (FDA) does not require animal testing for cosmetics, and alternative testing methods are widely available and lead to more reliable results."

• Cosmetic testing on animal skin is irrelevant to human skin.

• Cosmetic testing on eyes is faulty; caustic chemicals can be determined by chemistry. Humans can easily determine that a chemical is bad for the eyes simply by studying the pure chemistry involved, rather than putting an animal through intense pain and discomfort"

-http://debatepedia.idebate.org/en/index.php/Debate:_Animal_testing

Animal testing is not completely effective. Also most individuals would subject a family pet to this type of treatment - why should other animals experience these cruel and unusual conditions? There are plenty of alternatives to animal testing - using human cell cultures, computer models, willing and consenting humans, all of which are significantly more ethical and likely effective options.

How to make a Peanut Butter and Jelly Sandwich

Date Created: March 26, 2012

Created By: Brandon Alvarado, Sarah Richardson, Yvonne Rodriguez, Ellen Schneider, Elbert

Overview: This procedure details how to make a peanut butter and jelly sandwich step by step.

Supplies: 

Crunchy or Smooth Peanut Butter

Your choice of Jelly (Raspberry, Blackberry, Blueberry, Mixed Berries)

Your choice of Wheat of White Bread

Equipment:

Plate

Knife

Spoon

Procedure:

1. Pull out two slices of bread out of the bag of your choice and place them on your plate.
2. Dip the knife in the peanut butter and spread on one side of one slice of bread. 
3. Dip the spoon in your choice of jelly and spread on one side of the other slice of bread.
4. Place one piece of bread on top of the other, so that the peanut butter and jelly touch.
5. Use the Knife to cut the sandwich in half or in quarters.
6. Wash the utensils used.
7. Enjoy your sandwich.

Quality Control: To make sure your peanut butter and jelly sandwich was made correctly check for two things:

No peanut butter or jelly is on the outside of the bread

It tastes GOOD.

Phlogiston Theory

WHAT?

"a nonexistent chemical that, prior to the discovery of oxygen, was thought to be released during combustion" - http://dictionary.reference.com/browse/phlogiston

WHO?
Robert Boyle, Joseph Black, Joseph Priestly, Henry Cavendish, Antoine Lavoisier - http://web.fccj.org/~ethall/phlogist/phlogist.htm

WHEN?
Latter half of the 17th century; lasted for 100 years. - http://web.fccj.org/~ethall/phlogist/phlogist.htm
WHY (was it abandoned)?

"Eventually, quantitative experiments revealed problems, including the fact that some metals, such as magnesium, gained weight when they burned, even though they were supposed to have lost phlogiston. Mikhail Lomonosov attempted to repeat Robert Boyle's celebrated experiment in 1753 and concluded that the phlogiston theory was false." - http://en.wikipedia.org/wiki/Phlogiston_theory

Burgess Shale Creatures

Canadaspis perfecta (a crustacean)

Researchers have encountered the Canadaspis perfecta over 4,000 in the Burgess Shale. Its structure and bodily functions have been the subject of many research intiatives. As a crustacean, it is an early ancestor of crabs and lobsters. It has a segmented tail, a chitinous shell surrounding its body, and walking legs equipped with gills. The functions of these body parts are only speculative, conclusive results have not been reached.

 For more information... http://www.fossilmuseum.net/Cambrian-Explosion/Canadaspis-perfecta/CE05.htm

A helpful article conerning deductive/inductive reasoning

DEDUCTIVE VERSUS INDUCTIVE REASONING

Inductive and deductive reasoning are two methods of logic used to arrive at a conclusion based on information assumed to be true. Both are used in research to establish hypotheses.

Deductive reasoning arrives at a specific conclusion based on generalizations. Inductive reasoning takes events and makes generalizations

Deductive reasoning is reasoning that involves a hierarchy of statements or truths. Starting with a limited number of simple statements or assumptions, more complex statements can be built up from the more basic ones. For example, you have probably studied deductive geometry in mathematics; in it you start with a few principles and prove various propositions using those principles. To prove more complicated propositions, you may use propositions that you have already proved plus the original principles. In more formal logic terms deductive reasoning is reasoning from stated premises to conclusions formally or necessarily implied by such premises.

Deductive reasoning can be described as reasoning of the form if A then B. Deduction is in some sense the direct application of knowledge in the production of new knowledge.

If-then deductive reasoning is how scientists (and other people!) can test alternate hypotheses. Making deductions is important when we cannot directly observe a cause, and can only observe its consequences. This kind of reasoning can be modeled by the following:

If ...

Then...

But...

Therefore...

For example, we might hypothesize that "The color of a mineral is determined by its crystal structure."

And so we could test this hypothesis using deductive reasoning:

If the color of a mineral is determined by its crystal structure; then all purple minerals should have the same crystal structure. But purple amethyst has a hexagonal structure and purple fluorite has an isometric structure (determined by observations). Therefore, the hypothesis is not supported or strengthened.

Inductive reasoning is essentially the opposite of deductive reasoning. It involves trying to create general principles by starting with many specific instances. For example, in inductive geometry you might measure the interior angles of a group of randomly drawn triangles. When you discover that the sum of the three angles is 180° regardless of the triangle, you would be tempted to make a generalization about the sum of the interior angles of a triangle. Bringing forward all these separate facts provides evidence in order to help support your general statement about the interior angles.

This is the kind of reasoning used if you have gradually built up an understanding of how something works. Rather than starting with laws and principles and making deductions, most people collect relevant experience and try to construct principles from it.

Again the distinction between the two types of reasoning is not always sharp. In mathematics it is important to know which kind of formal system you are using and to stick to it. Inductive proofs are not allowed in a deductive system.

Inductive reasoning progresses from observations of individual cases to the development of a generality. (Inductive reasoning, or induction, is often confused with deductive thinking; in the latter, general principles or conditions are applied to specific instances or situations.) If a child puts his or her hand into a bag of candy and withdraws three pieces, all of which are red, he or she may conclude that all the candy is red. Inductive reasoning, or induction, is the process by which a general conclusion is reached from evaluating specific observations or situations.

Many people distinguish between two basic kinds of argument: inductive and deductive. Induction is usually described as moving from the specific to the general, while deduction begins with the general and ends with the specific; arguments based on experience or observation are best expressed inductively, while arguments based on laws, rules, or other widely accepted principles are best expressed deductively.

  SOURCE: http://www.nakedscience.org/mrg/Deductive%20and%20Inductive%20Reasoning.htm

Burgess Shale - Google Earth