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New species since humans?Moderator: BioTeam
35 posts • Page 1 of 3 • 1, 2, 3
New species since humans?The perception in much of the religious world is that humans (more specifically homo sapiens) were the last life form created on earth. I realize evolution says they weren't "created" at all, and that there were other "humans" before homo sapiens. Those issues aside for the moment, is there evidence of animal or plant species that came into being after modern humans were already on this planet?
Oh yes. There is a long list of Observed Speciations both in the lab and in nature. For example, Humans created the new genus Triticale by crossing rye and wheat. A natural hybridization occurred in the last 50 years between common groundsel and the Oxford ragwort in England. New species of Cichlid fishes evolved in lakes in East Africa in the last 300,000 years.
Also, there are Ring Species, which show speciation in action. In these cases, populations that undergo genetic variation (subspecies)form a circle or loop where adjacent variants interbred, but those at either end do not, even where meet. Examples include: Larus gulls, Ensatina salamanders, and the Greenish Warbler.
Re: New species since humans?Yes, I've heard of the gull situation, but didn't know when that took place. You mentioned cichlids in the past 300,000 years. So a question I should be clear on now is "how far back to modern humans date?"
Re: New species since humans?
OK. The diverisfication of 14 Cichlid fish species in Lake Victoria took only 12,000 years, since the lake was dried up for 5,000 years, until about 12,000 years ago. http://hagblomfoto.com/article_evolution.htm Humans evolved in East Africa about 200,000 years ago, so that puts these species in the timeframe you asked about.
but you must bear in mind natural selection does not account for the generation of species as colin leslie dean has pointed out http://gamahucherpress.yellowgum.com/bo ... ection.pdf this sites definition of NS is
so if a trait appears in an off spring which is not present in its parents then that shows ns is wrong as ns is about traits already present i being passed on as colin leslie dean has argued
you must also bear in mind that biologist dont know what species is http://en.wikipedia.org/wiki/Species
some say species interbreed but the case of the bactrian camel and dromardry camal which are considered different species can breed with fertile of spring this show that this definition of species ends in contradiction ie bactrian camel and dromardry camel inter breed should mean they are the same species but they are different species so should not breed but they do thus a contradiction thus all this talk in this thread about species speciation is really meaningless nonsence as colin leslie dean has shown biologist dont know what a species is or when they give a definition ie breeding together they end in self contradictionn Last edited by gamila on Wed Sep 16, 2009 2:42 pm, edited 1 time in total.
Re: New species since humans?Yes, I was under the firm belief that NS did lead the speciation.
as colin leslie dean has shown NS cannot lead to speciation- it is a logical impossibility http://gamahucherpress.yellowgum.com/bo ... ection.pdf
NS is -definition from this site [quote]It is the process by whichheritable traits that increase an organism’s chances of survival and reproduction are favoured than less beneficial traits. Originally proposed by Charles Darwin, natural selection is the process that results in the evolution of organism [quote]
Re:Instead of coming to a serious thread and quoting yourself in the third person over and over, try reading up on Population Genetics. Evolution is a change in gene frequency in a Population over time. Populations evolve, not Individuals.
as i said before if a trait appears in population which is not present in its parents population then that shows ns is wrong as ns is about traits already present i being passed on
Re:
NO, you said this: "if a trait appears in an off spring which is not present in its parents then that shows ns is wrong as ns is about traits already present i being passed on " Individuals in a population vary in their traits. The population evolves by changing the frequency of those traits.Thus, the average size, beak shape, coloration, etc. of a population can change over time, even without new mutations. This is the basic definition of natural selection as presented by Darwin. Read On the origin of Species if you don't believe me. Many traits are quantitative (under contol of many genes) and thus can change rapidly by this process. New mutations add to this variation over longer time frames.
35 posts • Page 1 of 3 • 1, 2, 3
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