If speciation can happen in 'low level' species, why not humans?

New (genetically new) species have arisen in historical times. For example: * A new species of mosquito, the molestus form isolated in London's Underground, has speciated from Culex pipiens (Byrne and Nichols 1999; Nuttall 1998). * Helacyton gartleri is the HeLa cell culture, which evolved from a human... show more New (genetically new) species have arisen in historical times. For example:

* A new species of mosquito, the molestus form isolated in London's Underground, has speciated from Culex pipiens (Byrne and Nichols 1999; Nuttall 1998).

* Helacyton gartleri is the HeLa cell culture, which evolved from a human cervical carcinoma in 1951. The culture grows indefinitely and has become widespread (Van Valen and Maiorana 1991).

* A similar event appears to have happened with dogs relatively recently. Sticker's sarcoma, or canine transmissible venerial tumor, is caused by an organism genetically independent from its hosts but derived from a wolf or dog tumor (Zimmer 2006; Murgia et al. 2006).

* Several new species of plants have arisen via polyploidy (when the chromosome count multiplies by two or more) (de Wet 1971). One example is Primula kewensis (Newton and Pellew 1929).
Update: In evolutionary biology today, macroevolution is used to refer to any evolutionary change at or above the level of species. It means at least the splitting of a species into two (speciation, or cladogenesis, from the Greek meaning "the origin of a branch") or the change of a species over time into another... show more In evolutionary biology today, macroevolution is used to refer to any evolutionary change at or above the level of species. It means at least the splitting of a species into two (speciation, or cladogenesis, from the Greek meaning "the origin of a branch") or the change of a species over time into another (anagenetic speciation, not nowadays generally accepted). Any changes that occur at higher levels, such as the evolution of new families, phyla or genera, are also therefore macroevolution, but the term is not restricted to those higher levels. It often also means long-term trends or biases in evolution of higher taxonomic levels. - So, if you're gonna say 'well that's not macroevolution, you are using your own Creationist definition of a scientific term, not its actual definition.
Update 2: See http://en.wikipedia.org/wiki/Evolution_of_the_horse also for 'transitional' fossil/bone records. Would you call a tiny horse with 4 toes the same species if it was alive today? From the same family, maybe, but totally different.
Update 3: 'Titanium...' - I believe in the generally accepted fact that humans have not changed as quickly as any of these examples. They are purely examples to illustrate how species can change. Humans, of course, as you say, would take longer due to their lifespans and slow birthing cycle. I also believe in the... show more 'Titanium...' - I believe in the generally accepted fact that humans have not changed as quickly as any of these examples. They are purely examples to illustrate how species can change. Humans, of course, as you say, would take longer due to their lifespans and slow birthing cycle. I also believe in the continental drift, so continents would have at one point, millions of years ago, been altogether, then gradually separated into the continents we have today. Humans, and many other animals species (or indeed their ancestors) may well have lived in one place at a certain time, then as continents split, certain groups would have ended up in totally different places, but likely evolved from the same common ancestor/been a similar species at one point in time. This continental drift theory is supported by the similarity in many species in South America and Africa, and in their shapes, that seem to 'fit' together.
Update 4: And Africa and Denmark are linked by land at any rate, so perhaps at one point they all lived at the North of Africa/South of Europe (as we know them today.)
Update 5: Why are people taking this question differently to how it was intended? I am not saying that the human species has changed as QUICKLY as others, merely that speciation can happen. I am well aware that human speciation would have to take millions of years.
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