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How does evolution make humans?
How does evolution make humans?
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How does evolution make humans?
25/11/2006 22:29:31 »
?'s about evolution always come up on this board, and alot of the time the question only exists because of the following superstitions. if anyone know better than i do, please correct me. really.
Superstition one: man is the apex of evolution
. .and is the winner of a natural competition.
Man is an animal. Disbelief or avoidance of this notion has existed since recorded history. Many respectable scientists and spiritualists alike point to mans many supposed “advancements” over other animals. They may include but are not limited to: the use of tools to create and hunt, the making and wearing of clothing, the creation of jewelry, the building of shelters and advancements in technology and sanitation, walking upright, complex communication, and empathy for people and other living things.
Obviously, man does have many unique properties as a species, but they need not be “advancements” any more spectacular than any other animals. Is a spider, who weaves a web to catch its pray more advanced than a man who expends energy chasing it? Is a chameleon, whose pigments blend with its surroundings any more advanced than a man of only one color? The answer is yes, and no. Every animal is specialized to its environment, which is different in any case. Believing any animal is more “advanced” is dependant on the criteria used.
A crocodile is advanced because it has not needed to adapt much or at all in some millions of years, along with most insects. A man is advanced because it has quickly developed complex means of communication within his species. A cobra is advanced because it has developed venom capable of not only defending itself but disabling pray. A whale is advanced because it is large. A flea is advanced because it is small. All of these things are advancements for the species itself, given what environment it lives in and the prey and predators that surround it. Animals should not be judged alongside one another, as a rhinos giant horn would not be advancement for a sheep and a sheep’s woolen fur would not be advancement for a rhino.
The most common argument posed is than mans adaptations are so unique that they are advancements beyond any another animals. The most common and ironic one believed is mans self-conciousness. Because a man is aware of itself, it supposedly poses some advantage in survival. While self-conciousness may be considered a blessing now, it may or may not be in millions of years. It is just as likely to be a curse to mankind as any other of its strange adaptations. Just because it is unique does not mean it is an advantage.
Superstition two: ape to man
A common misconception, originally arising from early interpretations of Darwinism and evolution, is that man evolved from apes. This was published and argued many times, and according to modern science and further study of fossils, is probably not true. In a textbook I own from the late 1960s, a diagram is drawn of “the modern theory of the decent of man”. It is numbered by animal, going from amoebas and protoplasm, to various fish, aquatic lizards, land reptiles, mammals, higher primates and then to man. Although this is not an attempt to include every animal and explain everything, it still shows the existance of 2 basic myths- the aforementioned idea that man is more advanced than other animals, and more importantly that evolution moves in a straight line.
To think evolution moves in a straight line, is to believe that one animal directly becomes another animal, and that that recently evolved animal becomes another. This is in conflict with observed natural selection. A species changes from a mutated gene. If this mutation is advantageous, it will prosper and the gene will be carried on, and none of the species will soon exist without the gene. So then, if an ape becomes a man, why do both still exist? The ape would have been rendered inferior to man. Evolution does not move in a straight line. It branches off; a huge family tree. Modern apes are our cousins, not our fathers. What man and modern apes share is most likely a mammalian prototype that lived billions of years ago. Because of changing climates or other factors, it became one or more other species, which in turn continued to develop into man and ape over millions of years.
It is however, unquestionable, that man has developed from one or several primates. These are however different than modern primates, as they lived among completely different species under different conditions than primates today.
Superstition three- the missing link
The widely sensationalized “missing link”, meaning an animal evolutionarily between modern man and modern ape, is an empty phrase. It is a fabrication arising from the misconception of what evolution is. Modern humans evolved from a prehistoric primate or possibly several of them. We would not have evolved if said primates were suitable for living anymore, as they would have no need to adapt.
Any animals found in recent history that are a species seemingly “in-between” modern apes and man evolved separately, and obviously, had to develop similar characteristics to be living in the same times both other animals are.
Superstition four- aesthetics
It is said that man is the only animal that has an eye for beauty and chooses its partners, surroundings, clothing and jewelry accordingly, regardless of the benefit or detriment to its own survival. This is partially true. Man is not the only animal that notices aesthetics. A famous incredible animal, the Irish elk, at the time of its sudden extinction, wore antlers 15 feet across, as observed from fossils. It was originally brought up as proof of creationism, as these massive antlers of the males could not possibly benefit its survival and are too strange to have evolved. After many studies attempting to suggest the antlers helped in fighting, which they may or may not have, it is most possible that it is simply what the females were attracted to.
The misunderstood and misinterpreted Darwin himself claimed that sexual selection was probably more a factor than survival selection in the current state of some animals. Sexual selection happens faster, as a gene can be bred out of bred into dominance just by selective breeding, while “survival of the fittest” is fierce competition over possibly a very long time. Sexual selection is unquestionable in humans. In only the last few centuries, though partially because of nutrition differences, humans are becoming taller and developing less body hair. Both common ideals of beauty, that seem to be against survival in some climates. Birds that develop plumage, fiddler crabs that develop an unusable claw, are both examples of similar situations.
Although humans are the only animal that makes jewelry and worries about if they are attractive, this is only a combination of other traits. If a man uses its hands to make its tools and home, and has an eye for aesthetics and what is attractive to it, jewelry naturally follows.
this isnt a near complete list of what i think are misconceptions about evolution but its a start.
Last Edit: 24/12/2006 09:06:55 by chris
Neilep Level Member
keep banging the rocks together
Re: How does evolution make humans?
Reply #1 on:
26/11/2006 10:29:17 »
As with many topics like this that keep coming back, your feelings that there are misconceptions are mostly based on deep thinking about the topic as presented in popular scientific literature. The essential simplifications of ideas presented in this sort of scientific literature often give rise to apparent misconceptions. I would advise you to study some more serious scientific texts on the subject and you will find that most of your ideas are valid but need to be placed in the concepts of the different types of selection processes that can cause a species to evolve. I cannot off hand reccommend very strongly any books at the moment but would suggest a look at the works of Richard Dawkins like "the selfish gene" and others as a starting point (but he has a few hangups about social development like religion). A good "popular book that I found gave quite a good overview of evolution generally is "the book of life" by Stephen Jay Gould which does admit its limitations and try to point out some common misconceptions created by other literature.
Learn, create, test and tell
evolution rules in all things
God says so!