I think the way you are going to have to approach this to make it understandable to nonscientists is by first explaining how the DNA of known close relatives looks, so we can see the relevance of the sequencing.
Known relatives (ie related by a few generations) would show up as 100% for the tests noted...since most of them examine highly conserved parts of the genome. Paternal tests do it differently.
Also please explain "nested hierarchy."
All of life falls into a nested hierarchy. I think I'll leave it up to an expert to explain:
http://evolution.berkeley.edu/evosite/lines/IVDhierarchies.shtml writes:
Evolution predicts that living things will be related to one another in what scientists refer to as nested hierarchies”rather like nested boxes. Groups of related organisms share suites of similar characteristics and the number of shared traits increases with relatedness. This is indeed what we observe in the living world and in the fossil record and these relationships can be illustrated as shown below.
Its the classic 'tree' which has a branch of verterbrates, which has sub-branches of reptiles, mammals etc which have sub branches which have sub branches. It forms a hierarchy with sub hierarchies...hence 'nested' hierarchy.
abe: I just remembered
this explanation (which I recommend you read)
29+ Evidences for macroevolution writes:
The difference between classifying cars and classifying languages lies in the fact that, with cars, certain characters (for example, color or manufacturer) must be considered more important than other characters in order for the classification to work. Which types of car characters are more important depends upon the personal preference of the individual who is performing the classification. In other words, certain types of characters must be weighted subjectively in order to classify cars in nested hierarchies; cars do not fall into natural, unique, objective nested hierarchies.
Because of these facts, a cladistic analysis of cars will not produce a unique, consistent, well-supported tree that displays nested hierarchies. A cladistic analysis of cars (or, alternatively, a cladistic analysis of imaginary organisms with randomly assigned characters) will of course result in a phylogeny, but there will be a very large number of other phylogenies, many of them with very different topologies, that are as well-supported by the same data. In contrast, a cladistic analysis of organisms or languages will generally result in a well-supported nested hierarchy, without arbitrarily weighting certain characters (Ringe 1999). Cladistic analysis of a true genealogical process produces one or relatively few phylogenetic trees that are much more well-supported by the data than the other possible trees.
I know we're generally encouraged to use our own wordings, but I feel that a well worded page like this one should be referred to first, if you need further clarification, gimme a shout.
Yes it does, because design-wise, as far as basic physical structure goes, chimpanzees ARE more similar to humans than turtles.
Indeed. However, this also works for those areas of the DNA which are known to have no effect on the morphology (the way an organism looks/physical structure). The classic example is cytochrome c. Its a protein that (as far as I am aware) all life has because it essential for cells to function properly. There are countless ways (ok, not countless, but its an astronomical number) to make functional cytochrome c.
The thing is, we know that the cytochrome c that humans have is perfectly functional in yeast. Cytochrome c can be used alone to detect relatedness, though it won't give totally accurate results it will give a good general trend.
This message has been edited by Modulous, Wed, 22-February-2006 05:52 PM
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