1,066
edits
Changes
Jump to navigation
Jump to search
Line 43:
Line 43: + + +
Debate:Is the theory of macroevolution true? (view source)
Revision as of 21:14, February 13, 2007
, 21:14, February 13, 2007→Yes: reply
I specified that evolutionary change is the dependent variable, or Y-value, bounded by a horizontal assymptote, with time as the independent variable, or X-value. Your second remark is entirely correct- I misused the word "species" when I meant to refer only to changes between breeds. Observation has shown that some dominant genetic traits tend to be passed on to an organism's offspring, but alleles place boundaries on the change that can occur through this process. It is true that it is difficult to quantify evolutionary change, since it does not appear to progress in any certain direction- another challenge to the above argument concerning the progress of evolutionary change over time. I chose a rational graph with the dependent variable bounded by a horizontal assymptote as an illustration because the aforementioned argument seemed to assume that evolutionary change could be expressed with respect to time or reproductive cycles by a linear graph. I chose the example of cross breeding because it is an example of the reproductive cycle being manipulated to produce maximum evolutionary change. The natural rate of change would be much slower, if indeed there were any measurable change. My statements about a dog "remaining a dog" and not changing species were meant only as examples of the genetic limitations of evolutionary change through natural reproduction, which is generaly limited by species, though somtimes by more inclusive levels of biological classification.
I specified that evolutionary change is the dependent variable, or Y-value, bounded by a horizontal assymptote, with time as the independent variable, or X-value. Your second remark is entirely correct- I misused the word "species" when I meant to refer only to changes between breeds. Observation has shown that some dominant genetic traits tend to be passed on to an organism's offspring, but alleles place boundaries on the change that can occur through this process. It is true that it is difficult to quantify evolutionary change, since it does not appear to progress in any certain direction- another challenge to the above argument concerning the progress of evolutionary change over time. I chose a rational graph with the dependent variable bounded by a horizontal assymptote as an illustration because the aforementioned argument seemed to assume that evolutionary change could be expressed with respect to time or reproductive cycles by a linear graph. I chose the example of cross breeding because it is an example of the reproductive cycle being manipulated to produce maximum evolutionary change. The natural rate of change would be much slower, if indeed there were any measurable change. My statements about a dog "remaining a dog" and not changing species were meant only as examples of the genetic limitations of evolutionary change through natural reproduction, which is generaly limited by species, though somtimes by more inclusive levels of biological classification.
: I'm not sure I completely follow some of what you said such as "Observation has shown that some dominant genetic traits tend to be passed on to an organism's offspring"- alleles are passed on just as frequently whether they are dominant or recessive. We are however, getting to the crux of the matter (although I incidentally note that you ignored the issue of discrete genetics), saying that change is "generaly limited by species, though somtimes by more inclusive levels of biological classification" is not useful. Beyond the species level all classification has a highly arbitrary element to it, at which point it isn't at all clear *why* you would presume that evolution at that level wouldn't occur (there is no sign of any magic barrier or such). This has also the incidental problem that speciation is in fact common. There are possibly hundreds of observed speciation events and I could easily provide (if you wanted) 10 or 15 of them and the relevant citations. (Also, many creationists support not just that speciation has occured but that rapid speciation occured right after the Deluge(indeed, in AIG's account this speciation happened far more uniformily and far faster than any biologist would ever predict and far faster than any observed level). To some extent this reflects a changing of the goalposts- 100 years ago no creationist acknowledged any form of evolution, then in the 1960s the evidence got overwhelming enough that the creationists conceded "microevolution" meaning evolution within species, and more recently many creationists now agree that evolution above the species level can occur, but not much above it. [[User:JoshuaZ|JoshuaZ]] 16:14, 13 February 2007 (EST)
#*'''Counter:''' Despite a century of teaching evolution in American schools, the majority of Americans still reject it. The burden of proof is on the evolutionists, and the proof just isn't there. Darwinists would be better off looking for another theory to try to replace Christianity.--[[User:Aschlafly|Aschlafly]] 23:54, 21 December 2006 (EST)
#*'''Counter:''' Despite a century of teaching evolution in American schools, the majority of Americans still reject it. The burden of proof is on the evolutionists, and the proof just isn't there. Darwinists would be better off looking for another theory to try to replace Christianity.--[[User:Aschlafly|Aschlafly]] 23:54, 21 December 2006 (EST)