why is evolution so slow?

Answer 1

Evolution occurs slowly because it is a product of genetic mutation, which happens at a slow rate. DNA replicates by a highly conserved process and when a mutation occurs in a genome it is usually purged by DNA replication mechanisms. However, when a mutation is not repaired it alters the genome of its host. If the uncorrected mutation occurs in an open reading frame (gene) then that mutation will be visible in the host as the mutation will be present in a protein that is mutated due to a DNA base change.
(Also the generation time answer provides another good aspect of why evolution seems to be slow.)
Most DNA mutations are seen as deleterious and are therefore purged by the process of natural selection. So the mutation rate is slow to start off with and then most mutations are removed fro mteh gene pool by natural selection. If a mutation is a good mutation that increases the fitness of the organism carrying it then the mutation must be spread throughout the population by means of reproduction. If the gene is spread through the population and reaches a stable frequency, or even if it just spreads through the population, the population is said to evolve. It takes a number of mutations to produce a significant difference between populations.

For speciation to occur populations pretty, much have to be separated geographically. (Yes there are other speciation mechanisms but this is the most common by far.) So even though one species may be changing over time it does not necessarily mean that the species will split into two species. Just look at the human lineage. Humanoid forms changed quite a bit morphologically since complete speciation from chimps. But it took quite a while for two races of humanoind forms (or humanoid species depending on your viewpoint formed) to evolve, the sapiens and neandethals.

On a species will diverge into two separate species after a period of 3 million years due to the slow mutation rates and requirements for speciation.

Answer 2

It's a function of generation time, as the basis for change is mutations in inheritable DNA.

That's why things that divide fast, for example bacteria, can basically be seen evolving in front of our eyes. One example out of many, many is that bacteria that weren't penicillin resistant for ~4 billion years ended up that way 20-50 years after the widespread introduction of penicillin.

There are bacteria that degrade all sorts of exotic compounds for energy. These are compounds that did not exist until recently. So if the bacteria derive energy solely from these compounds then it follows that that trait must have evolved after the introduction of thse compounds to the environment.

Answer 3

Because only slight changes happen to the genes every time two animals reproduce. And it takes many, many changes for an identifiable change to occur. So it really has to do with how DNA and genetics reproduce. They don't allow for huge changes to occur.

Answer 4

evolution need the time to pick out what to evol to and time to change the thing it is changing

Answer 5

because the changes literally take generations...it takes many rounds of offspring for most genetic changes to become prevalent

Answer 6

because transcription takes time, and then it takes time to see if the organism survives to perpetuate their genes

Answer 7

because it takes forever and a day for something to evolve.

Answer 8

Because if it was any faster it would be obvious that at least most parts of it aren't true.

Answer 9

what else would you like to evolve into

Answer 10

Yeah.........yawn......boring...just sitting waiting .....waiting......waiting.......(finger tap)....still hasn't happened.......