How many steps are there in human evolution?

Question

I know it was gradual, but how many obvious stages were there?

Answer 1

It all depends on how far back you want to go. I'll assume you want to go back from the beginning...

http://en.wikipedia.org/wiki/RNA_World
Stardust
Comet
Primordial Soup and/or clay
Organic goo
RNA replicator
Cell
Many many single celled organisms
Mitochondria and chloroplast join cell
Many many single celled organisms
Multicellular organism
Many many multicellular organisms
Vertebrate
Lungfish
Land lungfish
Various obscure animals
Mammals
Primates

At the stage of primates, the following is believed to have occurred...
http://en.wikipedia.org/wiki/Human_evolution#Before_Homo
"The evolutionary history of the primates can be traced back for some 60 million years, as one of the oldest of all surviving placental mammal groups. Most paleontologists consider that primates share a common ancestor with the bats, another extremely ancient lineage, and that this ancestor probably lived during the late Cretaceous together with the last dinosaurs. The oldest known primates come from North America, but they were widespread in Eurasia and Africa as well, during the tropical conditions of the Paleocene and Eocene. With the beginning of modern climates, marked by the formation of the first Antarctic ice in the early Oligocene around 40 million years ago, primates went extinct everywhere but Africa and southern Asia. The surviving tropical population, which is seen most completely in the upper Eocene and lowermost Oligocene fossil beds of the Fayum depression southwest of Cairo, gave rise to all living primates - lemurs of Madagascar, lorises of Southeast Asia, galagos or "bush babies" of Africa, and the anthropoids, i.e. platyrrhines or New World monkeys, and catarrhines or Old World monkeys and the great apes and humans.

The earliest known catarrhine is Kamoyapithecus from uppermost Oligocene at Eragaleit in the northern Kenya rift valley, dated to 24 Ma (millions of years before present). Its ancestry is generally thought to be close to such genera as Aegyptopithecus, Propliopithecus, and Parapithecus from the Fayum, at around 35 Ma. There are no fossils from the intervening 11 million years. No near ancestor to South American platyrrhines, whose fossil record begins at around 30 Ma, can be identified among the North African fossil species, and possibly lies in other forms that lived in West Africa that were caught up in the still-mysterious transatlantic sweepstakes that sent primates, rodents, boa constrictors, and cichlid fishes from Africa to South America sometime in the Oligocene.

In the early Miocene, after 22 Ma, many kinds of arboreally adapted primitive catarrhines from East Africa suggest a long history of prior diversification. Because the fossils at 20 Ma include fragments attributed to Victoriapithecus, the earliest cercopithecoid, the other forms are (by default) grouped as hominoids, without clear evidence as to which are closest to living apes and humans. Among the presently recognized genera in this group, which ranges up to 13 Ma, we find Proconsul, Rangwapithecus, Dendropithecus, Limnopithecus, Nacholapithecus, Equatorius, Nyanzapithecus, Afropithecus, Heliopithecus, and Kenyapithecus, all from East Africa. The presence of other generalized non-cercopithecids of middle Miocene age from sites far distant -- Otavipithecus from cave deposits in Namibia, and Pieroloapithecus and Dryopithecus from France, Spain and Austria -- is evidence of a wide diversity of forms across Africa and the Mediterranean basin during the relatively warm and equable climatic regimes of the early and middle Miocene. The youngest of the Miocene hominoids, Oreopithecus, is from 9-Ma coal beds in Italy.

Molecular evidence indicates that the lineage of gibbons (family Hylobatidae) became distinct between 18 and 12 Ma, and that of orangutans (subfamily Ponginae) at about 12 Ma; we have no fossils that clearly document the ancestry of gibbons, which may have originated in a so far unknown SE-asian hominoid population, but fossil proto-orangutans may be represented by Ramapithecus from India and Griphopithecus from Turkey, dated to around 10 Ma.

Molecular evidence further suggests that between 8 and 4 MYA, first the gorillas, and then the chimpanzee (genus Pan) split off from the line leading to the humans; we have no fossil record, however, of either group of African great apes, possibly because bones do not fossilize in rain forest environments. Hominines, however, seem to have been one of the mammal groups (as well as antelopes, hyaenas, dogs, pigs, elephants, and horses) that adapted to the open grasslands as soon as this biome appeared, due to increasingly seasonal climates, about 8 Ma, and their fossils are relatively well known. The earliest are Sahelanthropus tchadensis (7-6 MYA) and Orrorin tugenensis (6 MYA), followed by:

Ardipithecus (5.5-4.4 MYA), with species Ar. kadabba and Ar. ramidus;
Australopithecus (4-2 MYA), with species Au. anamensis, Au. afarensis, Au. africanus, Au. bahrelghazali, and Au. garhi;
Paranthropus (3-1.2 MYA), with species P. aethiopicus, P. boisei, and P. robustus;"

Answer 2

7

Answer 3

Hi. Human evolution has not stopped, just taking a break. The answer would involve calculating how many generations have developed since 'human' activity started. If each generation was 15 years (this is pre-society now) then dividing 3,000,000 (or a number of your choosing) by 15 would get you close.

Answer 4

Evolution is a continuum of gradual change. It is not divided into discrete steps, so your question is inane.

Answer 5

first there were the perfect humans created by god
then after sin they evolved into less capable beings flawed by sin
there lifespans began to decrease from 1000 years to no more than 120 humans became more and more incapable of intelligent thought the rejected their creator and began to contemplate other ways they could have arrived on the earth. now humans evolved from perfection to shrewed sinful beings with no hope apart from God.