MOLECULAR DATA
It occurred to me within the past day that I have ignored one of the things I learned in my youth - how to get some use out of discarded materials in the city dump!
Such experiences were something few children in modern cities get. So many of the products we use are not designed to be repaired, just throw the whole thing away and get a new one, or at best, get a module to replace a portion.
So my criticism of the Ecdysozoa and Lophotrochozoa studies [post of May 31, 2013] overlooked the fact that, if the errors introduced by linking most ancient ancestors were taken in to consideration, and some such ancestors were omitted in a new analysis, the remaining data might lead us closer to the reality of the ancestral paths. Even so, the inadequate sample sizes and the limited portion of the genomes examined are unlikely to be very useful.
I don't think it is worth trying because the sample sizes were already inadequate and might still be if clusters could be reanalyzed omitting the nematodes in the Ecdysozoa study. Nematodes need omission not only because they may have extreme retention of genomic identity giving them "long-branch attraction" to diverse distantly related groups, but they also are a separate lineage that is not basal to any other major modern group.
The Lophotrochozoa represent newer evolutionary events. Because uncertainty due to variable length of lineages from common ancestry of early coelomate animals, and the "long-branch attraction" problem affecting some of the members descended from annelids via the Pogonophora, the relationship of various "lophophorate" clusters can not be determined with simple corrections.
EMBRYOLOGICAL DATA
As discussed in my posts regarding isopod egg comparisons it is clear that the old idea of the "biogenetic law" where animals were thought to repeat some steps of their evolutionary development in their individual embryonic development is not valid. But I hope I made it clear that the concept is still a useful model that may suggest investigation for support from other evidence.
The isopod eggs, and ecological factors involved in deep-sea selection, helped me see how the Pogonophora explain the close relationship of ancestry of deuterostomes to advanced protostomes. Judging from the number of views of my blogs on the topics, I think people studying such things are unlikely to know about them and thus will be unable to apply the concepts.
ANATOMICAL DATA
Amazing data can be found in studies of anatomy. But it is increasingly unlikely to be helpful, not because it can't be, but because modern researchers are swamped with so much useful information they will never get far into older studies and approaches. Anatomy and its changes not only reflect evolutionary history but are intimately connected with the genomes of animals.
The environment imprints it natural selection role on structure, development, and the responsible genes. But the complex interaction is so nebulous I pity the researchers of today who are certainly more technically advanced than I have ever been. The day is not long enough, nor their life long enough, to have much chance of putting it all together. Still, I anticipate the continuation of the string of remarkable advances science can make in many areas. I hope they can still get the benefits study of the humanities can make in their lives.
Joseph G. Engemann Kalamazoo, Michigan January 23, 2015
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