Areas of Current Research
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Evolution of galactic morphologies 
M101
"The first step in the development of most sciences is a classification of the objects under study. Its purpose is to look for patterns from which hypotheses that connect things and events can be formulated... If the classification is useful, the hypotheses lead to predictions which, if verified, help to form the theoretical foundations of a subject."
Allan Sandage, 1975.
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A revised classification of galactic forms In 1923, Edwin Hubble wrote in a letter and manuscript that he sent only to V.M. Slipher that he was searching for "the thread of physical significance that shall vitalize a system of classification of non-galactic nebulae." In discussing the nebulae, Hubble seemed confident that an evolutionary sequence existed. "There is thus some grounds for using the terms early type and late type spirals and considering the elliptical nebulae and spirals as a single evolutional sequence." Yet when he published his classificatory scheme in 1926, Hubble retreated from that vision and stated that his classifications were "based primarily on the structural forms of photographic classification which should be entirely independent of theoretical considerations." However the process of classification and the simultaneous identification of an underlying organizing principle cannot be easily separated from one another philosophically. One begets the other. The work reported here offers such a "vitalizing thread," albeit in reversed order from the sequence originally envisioned by Hubble for the evolution of spirals. Our current understanding of the evolution of galactic morophologies remains filled with a significant number of unresolved puzzles. The unconventional argument advanced in this work is that episodic expulsions of collimated mass from the galactic nucleus are the generative processes that forms galactic bars, and in turn all of the "grand design" galactic forms. Nonetheless, it is this putative process that makes the evolutionary sequence mechanistically simple and coherent, as outlined in this modified Hubble diagram:
A corollary to the argument is that these mass expulsions are "written" rather indelibly onto a dark matter frame that surrounds the galactic nucleus. The more commonly argued hypothesis regarding the evolution of galactic morphologies is more prosaic: the observed structures are the result of recurrent gravity density waves circulating through the orbiting gas surrounding the galactic nucleus. However, the computational models produced to date have not been particularly satisfying. Newtonian/Keplerian considerations do not appear to be sufficient to explain the evolution of galactic morphologies. These two hypotheses are sufficiently distinct that tests discriminating between the two theses are easily described, and seven such tests are outlined in the work presented below.
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Biogeography & the distribution of species 
o The rate at which relaxation occurs will be faster for small
reserves than for large ones.
o Different species require different minimum areas to support
an enduring population.
J.M. Diamond, 1975. The island dilemma: lessons of modern
biogeographic studies for the design of natural preserves.
Biological Conservation 7:129-146.
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Measuring species extinction order Species distributions within naturally fragmented habitat have been found to often exhibit patterns of pronounced nestedness. Highly predictable extinction sequences are implied by these nested species distribution patterns, thus the patterns are important to both the philosophy and practice of conservation biology. The mechanism that creates this pattern of ordered extinctions appears to be quite straightforward: it is the differing minimum sustainable habitat area requirements of the various species that populate an archipelago of islands. As island area shrinks, there will always be one species more at risk of local extinction than any other due to its areal requirements. As island area continues to decrease and the most suspectible species disappears, another species takes its place as the species-most-at-risk. If this pattern is reliably repeated, island-to-island, then a pattern of nested subsets of species occupation is created. The work reported here attempts to measure the extent of the nestedness order in presence-absence matrices, as well as to provide a risk assessment of the extinction probability of the various species' populations isolated on islands of fragmented habitat. All physical observations are a mixture of signal and noise. Nestedness is no different. The continuum that exists between the extremes of complete order and complete randomness can be described in the simplest of thermodynamic terms. A perfectly ordered system (perfectly nested), absent of all randomness, may be described as maximally "cold" (0°). Similarly, a system absent of all order may be labeled as maximally "hot" (100°). A presence-absence matrix that contains both a degree of nestedness order and randomness will register an intermediate "temperature" between these two end-points. A Windows-based nestedness "temperature" calculator has been developed to calculate the degree of nestedness order within a species presence-absence matrix and is available for immediate downloading from the Field Museum of Natural History's web site. The calculator includes 294 presence-absence matrices taken from the primary ecological literature.
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Sexual selection & the maintenance of germline informational integrity 
Skull of the male Babirusa Pig
"In the full-grown male Babirusa pig of Celebes, the lower tusks
are formidable weapons, like those of the European boar in the
prime of life, whilst the upper tusks are so long and have their
points curled inwards, sometimes even touching the forehead, that
they are utterly useless as weapons of attack."
C.R. Darwin, 1875. The Descent of Man and Selection
in Relation to Sex. 2nd Ed. p. 518.
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Males act as a sacrificial defect filter The information borne in germline DNA cannot be indefinitely replicated, generation-after-generation, without decay. An inescapable entropy is infused into the germline at each generational juncture, eventually causing the senescence of the structures that the information encodes. The observed mutation rate of a lineage, m, is not the basal thermodynamic error rate affecting germline DNA. Rather it is the residual error that has passed uncorrected through whatever cellular repair mechanisms exist. The principal reason for the maintenance of males in the Metazoa appears to center on the necessity of evolving a gender of exaggerated pugnacity and increased physiological fragility, a gender that acts as a last-chance, pre-zygotic filter of these uncorrected genetic defects. A variety of genetic mechanisms promote a general physiological fragility in male animals that is not apparent in females, haplodiploidy being the most obvious. This fragility and relative sacrificiality is argued to serve a fundamental informational purpose: congenital defect exposure and expurgation from the germline. Otherwise, the value of males to a sexual species is unclear. The evolution of two sexually distinct genders is unneccesary to achieve the advantages commonly ascribed to sex. Protracted demonstrations of competitive vigor are common in male animals, especially within polygynous species. The two primary hypotheses that underlie much of the current work are:
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Evolutionary Computation 
"The control that natural selection exercises over random variations is somewhat like an engineer's idea of negative feedback: constant comparison between the representation of the world and new information coming in from it, and constant adjustment and readjustment in the light of that comparison (Young, 1957). The end result, adaptation, simulates deliberate, conscious design." H. Cronin, 1991. The Ant and the Peacock: Altruism and Sexual Selection from Darwin to Today p. 17. J.Z. Young, 1957. The Life of Mammals, pp 23-27. |
Evolving intelligence in machine form The simulation of evolution on computers for the purposes of parameter and function optimization has generally proven itself to be a robust and rapid optimization technique. But it seems reasonable to expect that there exists far more value in simulating evolution on computers than simple parameter optimization. The optimization of system behavior through simulated evolution represents a potentially powerful -- and perhaps the only -- autopoeitic pathway to machine learning and self-organization. Simulated evolutionary optimizations, as a machine intelligence technique, are still in their infancy, yet they are nonetheless a mechanism of machine learning that can reasonably be expected to continue to grow in importance and practical benefit. As the availability of massively parallel processors becomes increasingly common, the value of simulated evolutionary techniques will become increasingly apparent, if for no other reason than the natural match between the technique and the emerging technology. The power of simulated evolutionary techniques cannot be easily exaggerated. The method has been repeatedly demonstrated to successfully find points of global optimality, often astonishingly quickly, when other more traditional methods fail. While the process of simulating evolution is still very young, specific rules have become apparent and are easily stated. There are, however, extremely difficult problems that remain to be resolved -- and indeed, have not yet even been adequately addressed.
Related Material
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The search for
a second genesis of life
"Dreams about the modes of creation... [are] too idle to be worth a single hour of any man's life." Thomas Jefferson, 1804 |
A series of popular articles on astrobiology The new science of astrobiology is transforming our biological perspective, in the same manner that the emerging physical sciences of geology and geophysics did during Darwin's time. Throughout the past century, as our understanding of the forces impinging on the evolution of life on this planet has expanded, our understanding of the role of the astronomical environment on Earth's evolution has simultaneously grown, beginning initially with small curiosities to increasingly one of now being seen as governing life's path. The following is a series of columns on astrobiology written for the High Desert Observer, the newsletter of the Astronomical Society of Las Cruces, New Mexico, an amateur astronomical society. Material available in PDF format
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High-Quality On-Line Science 
"Our heritage and ideals, our codes and standards — the things we live by and teach our children — are preserved or diminished by how freely we exchange ideas and feelings." Walt Disney
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Low-bandwidth, world-wide lecture distribution Internet technologies possess obvious promise for the dissemination of instructional material over very large distances and into remote corners of the world. To that end, AICS Research has created two products, QCShow, a freely-downloadable player, and QCShow Author, an inexpensive content authoring tool that produces very high-quality audio and image slideshows at very low bandwidths. As an adjunct to that development process, AICS Research has been recording at its own expense the very highest quality conferences in cosmology, astronomy, planetology, geology, astrobiology, ecology, behavior and evolutionary biology so that these presentations may be viewed by anyone anywhere in the world.
Example Lecture sets available
Why the emphasis on low-bandwidth? Bandwidth is like money. If you have more than you need, you never think about it. But if you don't, it's all you think about. 150 million people in the United States are estimated to have internet access, but in early 2005 only 26.4 million of those have broadband access (16.7 million cable subscribers; 10.6 million for DSL). But there are two other overriding reasons for low-bandwidth designs. They are:
The second great attribute of low-bandwidth encodings is that they imply small file sizes, both on the server and in the client. Because of the high compression levels used in QCShow, the file sizes associated with QCShow lectures tend to be quite small. A 45-minute classroom lecture generally consumes about 10 MB, thus a standard 39-session college semester class will require only slightly more than half a CD to store. Perhaps even more interesting, all of the core lectures for an entire four-year college education can be stored onto a single DVD. These small file sizes also allow — in areas of the world where internet connections are not readily available — large libraries of QCShow-formatted lectures to be distributed on CDs or DVDs very inexpensively.
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Biography of Wirt Atmar.
AICS Research commercial home page.