"Hass, C. A., M. DiRado, L. R. Maxson, and S. B. Hedges. 1999. Relationships and biogeography of West Indian hylid frogs: an analysis of serum albumin transcript sequences. Joint meeting of
ASIH, HL, and SSAR. Penn State. 6/29/99.
Hass, C. A., L. R. Maxson, and S. B. Hedges. 2001. Relationships and divergence times of West Indian amphibians and reptiles: Insights from albumin immunology. Pp. 157-174. In C. A. Woods
& F. E. Sergile (eds), Biogeography of the West Indies: Patterns and Perspectives. 2nd edition, CRC Press.
Maxson, L.R. 2001. Micro-Complement Fixation (MC’F). In Encyclopedia of Genetics. W. A. Fitch et al., eds. Academic Press.

Note also that most of the sero-albumin work she has done of late is in CONJUNCTION with mtDNA work . . . the thing is, mtDNA and microsat nuclear DNA simply give so many more characters to evaluate than sero-albumin . . ."

Troy cited a large number of papers by Linda Maxson, in which mtDNA was used. However, he has also noticed that her most recent writings dealt with serum albumin. That supports my earlier assertion that immunological data has not been supplanted by more recently developed techniques and my assertion that Maxson would be the last person on earth to suggest that her immunological data should be discarded or ignored. As I pointed out, the ease with which DNA can be sequenced makes immunological techniques unattractive to the new generation of systematists, especially since the older technique often requires the sacrifice of a live animal if it is small, whereas a small tissue sample from a roadkill or even a preserved specimen is all that is needed with some of the newer techniques. mtDNA has even been extracted from the skull of a Neanderthal.

But as I pointed out earlier as well, serum albumin is a neutral molecule in which amino acid substitutions are unconstrained by natural selection. As such it is an excellent molecule with which to estimate relative lineage ages and timing of divergence events, since amino acid substitutions and the underlying nucleotide substitutions are more clock like than most molecules, even mtDNA, since mtDNA is still a functional molecule. As one can see from the last few papers listed above, immunological data was used for estimating lineage age and divergence times.

Unfortunately, Troy has very little understanding of the advantages of using neutral characters to determine phylogenetic relationships. Hence he thinks he can simply ignore Maxson's immunological data. It is not a good idea to ignore scientific data. Troy is apparently trying to justify dismissing immunological data by showing us that Maxson herself has turned to mtDNA in some of her recent studies. What Troy fails to understand is that mtDNA data does not invalidate immunological data any more than the invention of an electrical nailing gun makes a house built with a hammer a piece of junk. The electrical nailer simply makes buiding houses faster; its use does not guarantee the building of a better house. Similarly, mtDNA data is not necessarily better than immunological data. In some cases, it can even be worse, if one is not careful about choosing an outgroup for example. Immunological techniques and mtDNA sequencing are both tools for the systematist. In the hands of a knowledgeable systematist, either of these tools can be equally effective in constructing a sound phylogeny. In the hands of an inexperienced systematist, they can produce anomalous results.

Of course, it also takes knowledge to be able to judge the results of a systematic analysis. Those who lack the ability to judge the results and/or conclusions of a systematic analysis will simply turn to the Troy method: simply accept the newest data as the most accurate because they must be the best if they are using the latest techniques. Life would be too simple (and boring) for the systematist if the Troy method works, since all one has to do is to obtain a nose ring and attach it to the Troy method. Unfortunately, the Troy method does not work. Life is therefore not simple for the systematist. Nor is life boring for the knowledgeable systematist.

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