The hypothesis says, that all species evolved over time from a single common ancestor, through gradual beneficial variations, which has accumulated over millions of years.
This hypothesis is invalid due to the following:
The eye, ear and any other irreducibly complex systems could not have evolved by "slight beneficial variations" as each part is completely and utterly worthless if simple one of the pieces are missing.
Many more scientific counter-evidences can be presented, though the above should be enough for any honest supporter of evolution to abandon the hypothesis.
This logical evidence disproving evolution has not posed much of a problem, due to the fact that supporters of the hypothesis have suspended the use of logic and rationality.
The supporters of evolution have, in their desperate search for evidence to back up the hypothesis, uncovered more than 100 million fossils, all showing that species appeared suddenly, out of nowhere and fully formed, not by gradual changes.
The few so called transitional forms that have been uncovered are simply birds with teeth claimed to come from dinosaurs, dogs with wider tails claimed to be whales and humans with slightly smaller skull capacity claimed to be apes.
These overwhelming empirical counter-evidences have caused the supporters of evolution to become fanatic in their belief, and the "scientific" hypothesis has moved away from science and turned into more of a religious belief.
Evolutionist propaganda can be found in any biology text book, where the dis-proven hypothesis is portrayed as fact. The propaganda authors loves to demonstrate the evolution of man from ape with a line, showing a chimp morphing into a human. This line is totally fictious, a product of the authors imagination and has no basis in the fossil record.
Many supporters find the lack of evidence so embarrassing, they have crafted fossils to prove it, such as piltdown man.
Facing this utter lack of evidence, and abundance of counter-evidences, the supporters of evolution simply attacks any one questioning the hypothesis, refusing any kind of debate and simply labeling the refuter as a "Religious fanatic!!!". They try to portray the hypothesis as a fact, and loves to bring forth completely unfounded claims such as "Evolution is as much a law as gravity".
Normal person: Can you provide any proves?
Evolutionist: uhmmmmm... get out of here, you religous fanatic!
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.
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.
2. The fossil sequence of horses is an excellent example of evolution
2. In everyday speech: A gradual process in which something changes into a different and usually more complex or better form.
2. It is interesting to note the evolution in computers over the years.