Sarutobi sasuke
Is an Ape
*Updated 17/08/08*
New title thanks to Vindicare
It has come to my attention that there are aspects of this forum that do not think that Evolutionary theory is valid, I have even come across some posts saying it is a myth. I could not disagree more. So allow me set out the case for Evolution, what it is, the evidence for it and the common misconceptions of its critics.
I have tried to make my arguments and explanations in simple terms so that they will be understood if this upsets any scientist out there then I apologise in advance.
What is Evolution and how does it work
In simple terms the Theory of Evolution describes how life changes from generation to generation and how over many generations these changes can result in new species.
This is based on three basic principles
1. All life dies
2. All life reproduces with variation
3. Life that is not suited to its environment will die sooner than life that is. This is known as Natural selection
Reproduction with variation,
Offspring are not exact copies of their parents, this due to the fact that offspring inherit some traits from their father and some from their mother, also their siblings differ from them as they have inherited different traits from their parents.
How does this occur? Well all life is made of living cells and in these cells there are Chromosomes. Chromosomes are the organised structures of Genes. Genes are made from DNA, and DNA is a complex molecule that contains the information needed to create life, it is in effect a metaphorical instruction book.
Different forms of life have different numbers of chromosomes but for the sake of simplicity and familiarity Humans will be used as an example. Human have 46 chromosomes and they are arranged in pairs so it is more accurate to say that humans have 23 pairs of chromosomes. So each Human cell contains 46 chromosomes in 23 pairs. However there is one type of cell that only contains half the number of chromosomes 23 and they are not arranged in pairs, these are Gametes (sex cells) which are obviously the egg cells in females and sperm cells in males. So a child will inherit 23 from a possible 46 from its father and 23 from a possible 46 from its mother, so child now has complete set of 46 chromosomes. This reshuffling process means the child is different to both its parents.
DNA however can be changed in a process known as mutation. This is a random process. When cells divide for example in a developing embryo DNA makes a copy of itself this copying process is almost always accurate however on occasion this process creates an imperfect copy thus changing the gene and the metaphorical instruction book. Mutations are not only caused by imperfect duplication they are also known to be caused by Radiation, certain chemicals, and viruses coming into contact with DNA. These changes impact the organism in different ways for example some may make it slightly larger some may make slightly smaller some will have no effect and some will be fatal.
Here is a video that talks about mutations
[YOUTUBE]TU-7d06HJSs[/YOUTUBE]
And some links provided by other forum members
Natural selection
Natural selection is the mechanism which drives evolution. All organisms live in an environment and must overcome certain environmental pressures to survive.
The traits an organism inherits from it parents and gains through mutation effect its chances of survival in an environment by giving an individual either advantages or disadvantages over other member of its species.
For example imagine a population of Sea Otters these animals breathe air but hunt under-water so while hunting for fish they need to hold their breath. Now how long an individual can hold it breath is dependent in part on its lung capacity, it is known that life reproduces with variation so no individual in this population should be identical therefore they should all have differing lung capacities. Logic would dictate that individuals with larger lung capacities would be more successful hunters and therefore better fed and more likely to reach sexual maturity and pass on its genes than individuals with a smaller lung capacity. Over time the small lung gene is eliminated and larger lungs become the norm. So it is said that the large lung gene is naturally selected.
Environmental change.
Of course organisms are not restricted to one type of environment, it may change around them for various climatological or geographical reasons or species can migrate. This obviously changes the environmental pressures acting on as species.
For example imagine a herd of antelope grazing on a savannah over time the savannah dries out and vegetation is becomes sparse and individuals with longer necks have access to a larger food source as they can reach leaves on trees and bushes. Thus more long necks reach sexual maturity than short necks and over time the long neck gene becomes more wide spread in the population. But now individuals with very long necks have the advantage and so the process continues.
However what if the savannah did not dry out but became more temperate and colder, vegetation is still abundant what would happen to our Antelope then? Obviously individuals with thicker hair would have the advantage and thus the process of natural selection would generate a population of hairy Antelope.
Speciation
Speciation occurs when the DNA between two or more populations becomes so different due to mutations and natural selection that those populations can no longer successfully interbreed. How can this happen? Well it as been shown that different environments exert different environmental pressures on a species and the species will evolve over time. However take the population of Antelope on the savannah as an example and split it into three groups: the first group stays in the savannah; the second migrates north in to a colder environment with a similar abundance of food; and the third group migrates south where it is drier and food is less abundant. The first population would remain largely the same as they are well adapted for their environment, the second would evolve thicker hair and the third longer necks. The isolation and the differing natural selection of genes would result in three populations so genetically different from each other that individuals from different populations can no longer breed successfully and you get three separate species that evolved from one common ancestor.
This article shows observed examples of speciation.
Here are some videos that explain evolution well.
[YOUTUBE]YZwUV-auY4w[/YOUTUBE]
[YOUTUBE]R_RXX7pntr8[/YOUTUBE]
The Evidence
Age of the earth
Evolution of new species takes a significant amount of time so for the abundance of life we see today to have evolved from a common ancestor the Earth must be old, very old and indeed it is. The Earth is estimated at being 4.54 billion years old
The Fossil record
A very large number of fossils have now been discovered and identified. These fossils serve as a chronological record of evolution. The fossil record provides examples of transitional species that demonstrate ancestral links between past and present life forms. One such transitional fossil is Archaeopteryx, an ancient organism that had the distinct characteristics of a reptile, yet had the feathers of a bird. The implication from such a find is that modern reptiles and birds arose from a common ancestor.
Some videos on the subject
[YOUTUBE]O4GdZOlPrX8[/YOUTUBE]
[YOUTUBE]XUcB_HiCKnM[/YOUTUBE]
Morphology
Different species share common features for example the human hand, a cats paw, a bats wing and a dolphins flipper all share the same bone structure.
Vestigial structures
Vestigial structures are morphological features that serve no purpose but did in an evolutionary ancestor one example of this in Humans is the semi-lunar fold the remnants of a third eyelid in the corner of the eye nearest the nose. This third eyelid or nictitating membrane to give its proper name is found in reptiles, birds and some other mammals such as polar bears.
Other vestigial structures found in humans are ear muscles, wisdom teeth, appendix, tail bone (coccyx) and body hair.
New title thanks to Vindicare
It has come to my attention that there are aspects of this forum that do not think that Evolutionary theory is valid, I have even come across some posts saying it is a myth. I could not disagree more. So allow me set out the case for Evolution, what it is, the evidence for it and the common misconceptions of its critics.
I have tried to make my arguments and explanations in simple terms so that they will be understood if this upsets any scientist out there then I apologise in advance.
What is Evolution and how does it work
In simple terms the Theory of Evolution describes how life changes from generation to generation and how over many generations these changes can result in new species.
This is based on three basic principles
1. All life dies
2. All life reproduces with variation
3. Life that is not suited to its environment will die sooner than life that is. This is known as Natural selection
Reproduction with variation,
Offspring are not exact copies of their parents, this due to the fact that offspring inherit some traits from their father and some from their mother, also their siblings differ from them as they have inherited different traits from their parents.
How does this occur? Well all life is made of living cells and in these cells there are Chromosomes. Chromosomes are the organised structures of Genes. Genes are made from DNA, and DNA is a complex molecule that contains the information needed to create life, it is in effect a metaphorical instruction book.
Different forms of life have different numbers of chromosomes but for the sake of simplicity and familiarity Humans will be used as an example. Human have 46 chromosomes and they are arranged in pairs so it is more accurate to say that humans have 23 pairs of chromosomes. So each Human cell contains 46 chromosomes in 23 pairs. However there is one type of cell that only contains half the number of chromosomes 23 and they are not arranged in pairs, these are Gametes (sex cells) which are obviously the egg cells in females and sperm cells in males. So a child will inherit 23 from a possible 46 from its father and 23 from a possible 46 from its mother, so child now has complete set of 46 chromosomes. This reshuffling process means the child is different to both its parents.
DNA however can be changed in a process known as mutation. This is a random process. When cells divide for example in a developing embryo DNA makes a copy of itself this copying process is almost always accurate however on occasion this process creates an imperfect copy thus changing the gene and the metaphorical instruction book. Mutations are not only caused by imperfect duplication they are also known to be caused by Radiation, certain chemicals, and viruses coming into contact with DNA. These changes impact the organism in different ways for example some may make it slightly larger some may make slightly smaller some will have no effect and some will be fatal.
Here is a video that talks about mutations
[YOUTUBE]TU-7d06HJSs[/YOUTUBE]
And some links provided by other forum members
The Onion
[Shinsen-Subs]_D.Gray-man_-_74_[54BDA99E].avi
Natural selection
Natural selection is the mechanism which drives evolution. All organisms live in an environment and must overcome certain environmental pressures to survive.
The traits an organism inherits from it parents and gains through mutation effect its chances of survival in an environment by giving an individual either advantages or disadvantages over other member of its species.
For example imagine a population of Sea Otters these animals breathe air but hunt under-water so while hunting for fish they need to hold their breath. Now how long an individual can hold it breath is dependent in part on its lung capacity, it is known that life reproduces with variation so no individual in this population should be identical therefore they should all have differing lung capacities. Logic would dictate that individuals with larger lung capacities would be more successful hunters and therefore better fed and more likely to reach sexual maturity and pass on its genes than individuals with a smaller lung capacity. Over time the small lung gene is eliminated and larger lungs become the norm. So it is said that the large lung gene is naturally selected.
Environmental change.
Of course organisms are not restricted to one type of environment, it may change around them for various climatological or geographical reasons or species can migrate. This obviously changes the environmental pressures acting on as species.
For example imagine a herd of antelope grazing on a savannah over time the savannah dries out and vegetation is becomes sparse and individuals with longer necks have access to a larger food source as they can reach leaves on trees and bushes. Thus more long necks reach sexual maturity than short necks and over time the long neck gene becomes more wide spread in the population. But now individuals with very long necks have the advantage and so the process continues.
However what if the savannah did not dry out but became more temperate and colder, vegetation is still abundant what would happen to our Antelope then? Obviously individuals with thicker hair would have the advantage and thus the process of natural selection would generate a population of hairy Antelope.
Speciation
Speciation occurs when the DNA between two or more populations becomes so different due to mutations and natural selection that those populations can no longer successfully interbreed. How can this happen? Well it as been shown that different environments exert different environmental pressures on a species and the species will evolve over time. However take the population of Antelope on the savannah as an example and split it into three groups: the first group stays in the savannah; the second migrates north in to a colder environment with a similar abundance of food; and the third group migrates south where it is drier and food is less abundant. The first population would remain largely the same as they are well adapted for their environment, the second would evolve thicker hair and the third longer necks. The isolation and the differing natural selection of genes would result in three populations so genetically different from each other that individuals from different populations can no longer breed successfully and you get three separate species that evolved from one common ancestor.
This article shows observed examples of speciation.
A paper published by J. Weiner in 2005 in Natural History entitled 'Evolution in action
Here are some videos that explain evolution well.
[YOUTUBE]YZwUV-auY4w[/YOUTUBE]
[YOUTUBE]R_RXX7pntr8[/YOUTUBE]
The Evidence
Age of the earth
Evolution of new species takes a significant amount of time so for the abundance of life we see today to have evolved from a common ancestor the Earth must be old, very old and indeed it is. The Earth is estimated at being 4.54 billion years old
The Fossil record
A very large number of fossils have now been discovered and identified. These fossils serve as a chronological record of evolution. The fossil record provides examples of transitional species that demonstrate ancestral links between past and present life forms. One such transitional fossil is Archaeopteryx, an ancient organism that had the distinct characteristics of a reptile, yet had the feathers of a bird. The implication from such a find is that modern reptiles and birds arose from a common ancestor.
Some videos on the subject
[YOUTUBE]O4GdZOlPrX8[/YOUTUBE]
[YOUTUBE]XUcB_HiCKnM[/YOUTUBE]
Morphology
Different species share common features for example the human hand, a cats paw, a bats wing and a dolphins flipper all share the same bone structure.
Vestigial structures
Vestigial structures are morphological features that serve no purpose but did in an evolutionary ancestor one example of this in Humans is the semi-lunar fold the remnants of a third eyelid in the corner of the eye nearest the nose. This third eyelid or nictitating membrane to give its proper name is found in reptiles, birds and some other mammals such as polar bears.
Other vestigial structures found in humans are ear muscles, wisdom teeth, appendix, tail bone (coccyx) and body hair.
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