Evolution

What is Evolution?


1.

The idea that organisms change over time, and that is change occurs through natural selection which allows favorable traits to be passed along through generations. It has been refered to as a theory, which, in science, means it is an idea that has not been disproven. Many scientists are moving towards calling it the Law of Evolution, similar to the Law of Gravity, in order to help reduce frivolous claims that it is "only a theory" by people ignorant of what a scientific theory entails.

Some (especially miseducated critics) refer to macro and microevolution. There is no such thing. Evolution is evolution. Fruit flys, rats, frogs, etc., have all been observed undergoing character change in laboritories, resulting in the inability to mate with other members of the base species (the control), thus forming a new species. Several examples of so-called macroevolution (the change at a genus level) have been observed by biologists in the rain forest. Furthermore, good fossil evidence shows transition between genera, and even higher taxanomic orders (incorrectly called Kingdom, Phylum, etc. - current work in phylogentic taxonomy does away with Linnean ranks). Representatives of higher order change in the fossil record includes change with fish, fish to amphibians, with amphibians, within reptiles, "reptiles" to dinosaurs, within dinosaurs, dinosaurs to "birds", within "birds", "reptiles" to mammals, within mammals, and other mammals to humans. I am not mentioning invertebrates here, as I do not deal with them in my line of work. See current molecular and physical phylogenetic phylogenies in Nature, Science, Journal of Vertebrate Paleontology, etc., all of which are peer reviewed, something most parties who oppose evolution will not do (publish in peer-reviewed journals).

Evolution has nothing to do with The Big Bang - that is astronomy, not biology.

The synthysis and subsequent radiation and adaptation of life is a wonderful and beautiful thing, and far more complex than the, "We don't look like fish, so can't have evolved," argument presented by many whom view evolution/natural selection as the work of the devil.

A good example of evolution is the fossil record showing the transition between fish and amphibians, or dinosaurs and birds.

2.

1. The process by which one state changes into another. Anything which is not static evolves over time. The word evolution specifically excludes any connotation of improvement or progress, so even 'negative' changes are evolution. In biology, this definition is often observed in terms of the change of gene frequencies in natural populations. There is no controversy about this definition.

2. The theory that species give rise to other species. This process of speciation can be accomplished in a number of ways, all of which must result in two (or more) populations becoming genetically isolated. This can be accomplished physically (allopatry and peripatry) or through division of patch types or through behavioral mechanisms (sympatry). This has been observed at low taxonomic levels. For instance, wheat is a modern species resulting from 2 instances of non-disjunction and one hybridization event that all occurred within the last 5000 years. The original plant has been identified from seeds from tombs in Egypt.

The creation of new higher level taxa is often referred to as macroevolution by non-scientists, but this usage is incorrect. The only difference between the origins of higher taxa and species is time. Today's species will eventually give rise to genera as they continue to diverge from their sister-taxa and continue to speciate themselves. All higher taxa were once just a species. Macroevolution properly refers to selection that operates above the species level, such as the selective pressure across the K-T boundary on gastropods which favored genera (but not species) with wide geographic ranges.

I'll note that theory is the most certain science ever is. In this case, it means that over the last century and a half, plus the observations from before the theory's proposal, no evidence has been found that contradicts the theory of evolution. By the same token, gravity is a theory, and thermodynamics is a theory. 'Law' is just scientific shorthand for a theory that no one thinks will ever be disproved, and may soon be applied to evolution.

1. The reaction was in a critical phase of its evolution.

2. The fossil sequence of horses is an excellent example of evolution

3.

1. In biology: Descent with modification. Change in the genetic composition of a population during successive generations, as a result of natural selection acting on the genetic variation among individuals, and resulting in the development of new species.

2. In everyday speech: A gradual process in which something changes into a different and usually more complex or better form.

1. Darwin's theory of evolution does for biology what quantum mechanics does for physics.

2. It is interesting to note the evolution in computers over the years.

See science, development, genetics, lions, tigers, humans, creation

4.

Something that "$LAYER" and other religous people continue to deny in incredibly lame fashion.

Billy: "Why don't people realize religion is obsolete and misleading?"

Me: "Because people are stupid and they don't understand thee concept of evolution."

See darwin, religion, stupid, god, monkey

5.

Evolution, the combination of such processes as Natural Selection, Sexual Selection, and others, is the subsequent collection of scientific processes that eventually change one organism into another. It is important to discount a few widely held myths here that Creationists often erroneously use to discount Evolution, bringing up half-baked ideas about how one or more "facts" disprove evolution, without bothering to actually know what they're talking about. However, a little care and attempt at education can easily clear up these mistakes:

1.) Evolution does NOT necessarily dictate that animals (or plants, or fungi, or whatever you fancy) must evolve into something more complex. If all animals over the size of cockroaches were wiped out tomorrow, that would be a form of evolution: the Cockroaches and smaller animals would be the surviving species, and "Survival of the Fittest" (a common saying used in evolution) would hold true.

2.) Evolution does NOT, I repeat NOT suggest that humans "magically appeared from crawling fish". Evolution takes time. HUGE amounts of time. We're talking about half a billion years here (~500,000,000)for the total evolution from the first protochordates into the modern Homo sapiens. Not a couple days. Not even a couple centuries. This time span is so long that it's often hard to comprehend. The changes were gradual, as some random "mistakes" in our DNA made some animals better able to adapt, and others not as able to adapt. It is NOT like throwing sand in the air and having it come down as a sand castle. It is, however, like sprinkling little tiny bits of sand here and there - sometimes a grain at a time - and eventually building up to a sandcastle. And sometimes having bits of the sandcastle knocked down.

3.) Species that died out, such as Homo neanderthalis (Neaderthal Man) are not counterexamples. In fact, it shows that two different species, with two different natural "sets of equipment", have different ways (and thus chances) of surviving or outlasting eachother. We and Neanderthals DID stem from the same common ancestor. However, whereas Neanderthals had stocky, tough, but not to bright build, we went the lean and brainy root. That was fine for a little while, but soon we outcompeted them, and they died out.

4.) In regards to the comment above that some species were found in the wrong area: The earth moves. Ever see a volcano? An earthquake? Rocks don't always just sit there.

5.) Any educated biologist will not respond by saying "oh, you're right, evolution didn't happen."

Bill: But monkeys and fish look real different, so evolution must be wrong! Fish change into monkeys suddenly? LOL!

Jill: That's not really what Evolution says...

See evolution, creation, creationism, philosophy, god, theology, science, debate

6.

1. Gradual change in life over millions of years, confirmed by both genetics and fossils. Anyone who's seen the evidence and still denies it likely has religious motivations.

2. Something that is clearly going downhill in the Bush family.

Homo habilis was a major milestone in the evolution from ape to man.

See darwin, natural selection, biology, life

7.

Any change in an organism or population, there is no such thing as good or bad evolution.

Grey bugs survive better on grey rocks than black bugs, this is evolution.

See Loller


57

Random Words:

1. The 1:16th scale, retarded love child between a Zamboni and a Street Sweeper. The Zambortion comes fully equipped with a retractible, fl..
1. Connecticut, also known as the "P," a liquour store. probably derived from the brown bags/packages the liquour comes in. If ..
1. An Italian guy with a very long beard, like the classic rock band ZZ Top. Anthony and Paul either need to shave, or start an act called..