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[DaoiCarpates]

Biological evolution is descent with modification. This definition encompasses small-scale evolution (changes in gene frequency in a population from one generation to the next) and large-scale evolution (the descent of different species from a common ancestor over many generations). Evolution helps us to understand the history of life. While evolution is very widely accepted, many people hold to misconceptions about it. This list should help to dispel some of those myths.

15. Evolution is a theory about the origin of life

The theory of evolution primarily deals with the manner in which life has changed after its origin. While science is interested in the origins of life (for example the composition of the primeval sludge from which life might have come) but these are not issues covered in the area of evolution. What is known is that regardless of the start, at some point life began to branch off. Evolution is, therefore, dedicated to the study of those processes.

14. Organisms are always getting better



While it is a fact that natural selection weeds out unhealthy genes from the gene pool, there are many cases where an imperfect organism has survived. Some examples of this are fungi, sharks, crayfish, and mosses – these have all remained essentially the same over a great period of time. These organisms are all sufficiently adapted to their environment to survive without improvement.

Other taxa have changed a lot, but not necessarily for the better. Some creatures have had their environments changed and their adaptations may not be as well suited to their new situation. Fitness is linked to their environment, not to progress.

13. Evolution means that life changed 'by chance'

In fact, natural selection is not random. Many aquatic animals need speed to survive and reproduce – the creatures with that ability are more suited to their environment and are more likely to survive natural selection. In turn, they will produce more offspring with the same traits and the cycle continues. The idea that evolution occurs by chance does not take the entire picture in to account.

12. Natural selection involves organisms 'trying' to adapt



Organisms do not "try" to adapt – it is natural selection that enables various members of a group to survive and reproduce. Genetic adaptation is entirely outside of the power of the developing organism.

11. Natural selection gives organisms what they 'need'

Natural selection has no "intelligence" – it can not tell what a species needs. If a population has genetic variants that are more suited to their environment, they will reproduce more in the next generation and the population will evolve. If a genetic variant is not present, the population will most likely do – or it will survive with little evolutionary change.

10. Evolution is 'just' a theory



Scientifically speaking, a theory is a well substantiated idea that explains aspects of the natural world. Unfortunately other definitions of theory (such as a "guess" or a "hunch") cause a great deal of confusion in the non-scientific world when dealing with the sciences. They are, in fact, two very different concepts.

9. Evolution is a Theory in Crisis

There is no debate in science as to whether or not evolution occurred – there is, however, debate over how it happened. The minutiae of the process is vigorously debated which can cause anti-evolutionists to believe that the theory is in crisis. Evolution is sound science and is treated as such by scientists worldwide.

8. Gaps in the Fossil Record Disprove Evolution



Actually, many transitional fossils do exist – for example, there are fossils of transitional organisms between modern birds and their dinosaur ancestors, as well as whales and their land mammal ancestors. There are many transitional forms that have not been preserved, but that is simply because some organisms do not fossilize well or exist in conditions that do not allow for the process of fossilization. Science predicts that there will be gaps in the record for many evolutionary changes. This does not disprove the theory.

7. Evolutionary Theory is Incomplete

Evolutionary science is a work in progress. Science is constantly making new discoveries with regard to it and explanations are always adjusted if necessary. Evolutionary theory is like all of the other sciences in this respect. Science is always trying to improve our knowledge. At present, evolution is the only well-supported explanation for all of life’s diversity.

6. The Theory is Flawed



Science is an extremely competitive field – if any flaws were discovered in evolutionary theory they would be quickly corrected. All of the alleged flaws that creationists put forth have been investigated careful by scientists and they simply do not hold water. They are usually based on misunderstandings of the theory or misrepresentation of the evidence.

5. Evolution is not science because it is not observable

Evolution is observable and testable. The confusion here is that people think science is limited to experiments in laboratories by white-coated technicians. In fact, a large amount of scientific information is gathered from the real world. Astronomers can obviously not physically touch the objects they study (for example stars and galaxies), yet a great deal of knowledge can be gained through multiple lines of study. This is true also of evolution. It is also true that there are many mechanisms of evolution that can be, and are studied through direct experimentation as with other sciences.

4. Most Biologists have rejected Darwinism



Scientists do not reject Darwin’s theories, they have modified it over time as more knowledge has been discovered. Darwin considered that evolution proceeds at a deliberate, slow pace – but in fact it has now been discovered that it can proceed at a rapid pace under some circumstances. There has not been, so far, a credible challenge to the basic principles of Darwin’s theory. Scientists have improved and expanded on Darwin’s original theory of natural selection – it has not been rejected, it has been added to.

3. Evolution Leads to Immoral Behavior

All animal species have a set of behaviors that they share with other members of their species. Slugs act like slugs, dogs act like dogs, and humans act like humans. It is preposterous to presume that a child will begin to behave like another creature when they discover that they are related to them. It is nonsensical to link evolution to immoral or inappropriate behavior.

2. Evolution Supports "Might Makes Right"



In the 19th and early 20th century, a philosophy called “Social Darwinism” sprung up from misguided attempts to apply biological evolution to society. This philosophy said that society should allow the weak to fail and die, and that not only is this an ideal situation, but a morally right one. This enabled prejudices to be rationalized and ideas such as the poor deserved their situation due to being less fit were very popular. This was a misappropriation of science. Social Darwinism has, thankfully, been repudiated. Biological evolution has not.

1. Teachers Should Teach Both Sides

There are tens of thousands of different religious views concerning creation. It is simply impossible for all of these views to be presented. Furthermore, none of the theories are based in science and therefore have no place in a science classroom. In a science class, students can debate where a creature branched off in the tree of life, but it is not right to argue a religious belief in a science class. The "fairness" argument is often used by groups attempting to inject their religious dogmas in to the scientific curricula.

[DaoiCarpates]

Top 10 Signs Of Evolution In Modern Man


Through history, as natural selection played its part in the development of modern man, many of the useful functions and parts of the human body become unnecessary. What is most fascinating is that many of these parts of the body still remain in some form so we can see the progress of evolution. This list covers the ten most significant evolutionary changes that have taken place – leaving signs behind them.

10. Goose Bumps (Cutis Anserina)



Humans get goose bumps when they are cold, frightened, angry, or in awe. Many other creatures get goose bumps for the same reason, for example this is why a cat or dog’s hair stands on end and the cause behind a porcupine's quills raising. In cold situations, the rising hair traps air between the hairs and skin, creating insulation and warmth. In response to fear, goose bumps make an animal appear larger – hopefully scaring away the enemy. Humans no longer benefit from goose bumps and they are simply left over from our past when we were not clothed and needed to scare our own natural enemies. Natural selection removed the thick hair but left behind the mechanism for controlling it.

9. Jacobson’s Organ (Vomeronasal organ)



Jacobson's organ is a fascinating part of animal anatomy and it tells us a lot about our own sexual history. The organ is in the nose and it is a special "smell" organ which detects pheromones (the chemical that triggers sexual desire, alarm, or information about food trails). It is this organ that allows some animals to track others for sex and to know of potential dangers. Humans are born with the Jacobson’s organ, but in early development its abilities dwindle to a point that it is useless. Once upon a time, humans would have used this organ to locate mates when communication was not possible. Single's evenings, chat rooms, and bars have now taken its place in the process of human mate-seeking.

8. Junk DNA (L-gulonolactone oxidase)



While many of the hangovers from our "devolved" past are visible or physical, this is not true for all. Humans have structures in their genetic make-up that were once used to produces enzymes to process vitamin C (it is called L-gulonolactone oxidase). Most other animals have this functioning DNA but at some point in our history, a mutation disbled the gene – whilst leaving behind its remnants as junk DNA. This particular junk DNA indicates a common ancestry with other species on earth, so it is particularly interesting.

7. Extra Ear Muscles (Auriculares muscles)



Also known as the extrinsic ear muscles, the auriculares muscles are used by animals to swivel and manipulate their ears (independently of their head) in order to focus their hearing on particular sounds. Humans still have the muscles that we would once have used for the very same reason – but our muscles are now so feeble that all they can do is give our ears a little wiggle. The use of these muscles in cats is very visible (as they can nearly turn their ears completely backwards) – particularly when they are stalking a bird and need to make the smallest movements possible so as to not frighten its future meal.

6. Plantaris Muscle



The plantaris muscle is used by animals in gripping and manipulating objects with their feet – something you see with apes who seem to be able to use their feet as well as their hands. Humans have this muscle as well, but it is now so underdeveloped that it is often taken out by doctors when they need tissue for reconstruction in other parts of the body. The muscle is so unimportant to the human body that 9% of humans are now born without it.

5. Wisdom Teeth



Early humans ate a lot of plants – and they needed to eat them quickly enough that they could eat a sufficient amount in one day to get all of the nutrients they needed. For this reason, we had an extra set of molars to make the larger mouth more productive. This was particularly essential as the body lacked the ability to sufficiently digest cellulose. As evolution made its selections, our diets changed, our jaws grew appropriately smaller, and our third molars became unnecessary. Some human populations have now all but completely stopped growing wisdom teeth, while others have almost 100% likelihood of developing them.

4. Third Eyelid



If you watch a cat blink, you will see a white membrane cross its eye – that is called its third eyelid. It is quite a rare thing in mammals, but common in birds, reptiles, and fish. Humans have a remnant (but non-working) third eyelid (you can see it in the picture above). It has become quite small in humans, but some populations have more visible portions than others. There is only one known species of primate that still has a functioning third eyelid, and that is the Calabar angwantibo (closely related to lorises) which lives in West Africa.

3. Darwin's Point (Plica semilunaris)



Darwin's point is found in the majority of mammals, and humans are no exception. It is most likely used to help focus sounds in animals, but it no longer has a function in humans. Only 10.4% of the human population still has this visible left-over mark of our past, but it is possible that a much larger number of people carry the gene that produces it as it does not always cause the ear tubercle to appear. The point (shown in the picture above) is a small thick nodule at the junction of the upper and middle sections of the ear.

2. Coccyx



The coccyx is the remnant of what was once a human tail. Over time we lost the need for a tail (as tree swinging was replaced by hanging out at the local water hole grunting Neanderthal gossip), but we did not lose the need for the coccyx: it now functions as a support structure for various muscles and a support for a person when he sits down and leans back. The coccyx also supports the position of the anus.

1. Appendix



The appendix has no known use in modern humans and is often removed when it becomes infected. While its original use is still speculated on, most scientists agree with Darwin's suggestion that it once helped to process the cellulose found in the leaf-rich diet that we once had. Over the course of evolution, as our diet has changed, the appendix became less useful. What is particularly interesting is that many evolutionary theorists believe that natural selection (while removing all of the abilities of the appendix) selects larger appendices because they are less likely to become inflamed and diseased. So unlike the little toe, which may eventually vanish and is equally useless, the appendix is likely to stay with us for a long time – just hanging around doing nothing.