Scanning electron microscopy has long been used by paleontologists for the detailed morphological study of fossil organisms. Often, however, as in studies of growth or diagenesis, the researcher is also interested in the chemical composition of the specimen. Traditional methods of chemical analysis, such as “wet” chemistry or atomic absorption, require destructive preparation (crushing, grinding, solution) and provide only bulk chemical analyses; there is no measure of the spatial distribution of elements.

A grain size analysis (including the carbonate fraction) was performed on sediment samples from each of the following environments of Bahia la Choya: tidal flat, spit, beach, and estero. The sediments of the tidal flat have an average grain size of 2.88 phi, range from very well sorted to moderately well sorted, and have a carbonate shell fraction ranging from 1 to 30%. The spit sediments have an average grain size of 0.96 phi, are moderately to poorly sorted, and have a carbonate shell fraction of approximately 50%. The beach sediments have an average grain size of 1.22 phi, range from poorly sorted to moderately well sorted, and have a carbonate shell fraction of approximately 48%. The sediments of the estero average 39% sand, 40% silt, and 20% clay. The carbonate fraction in the estero is approximately 25%. The noncarbonate fraction in all the environments is made up of feldspar, quartz, biotite, heavy minerals, and igneous rock fragments.

The major source for the sediment is the Pelican Point granite on the south side of the bay. Pleistocene rock in and around the bay provides a second source of sediment and volcanic rocks to the north may also contribute to the sediment.

COLLECTIONS OF invertebrate fossils are commonly maintained in museums, at universities, and by individual researchers and interested private collectors. Twenty years ago, the Committee on North American Resources in Invertebrate Paleontology (CONARIP) estimated that there more than 550 institutions housed invertebrate paleontological macro- and micro- fossil collections (Glenister, 1977). Historically, collections have been developed, managed and maintained by paleontologists as a resource for their research (e.g., museum curator or university faculty) (Hebda, 1985). Since the early 1970s, the field of collection management has evolved and the increased professionalization of collection manager positions has been instrumental in improving the management and preservation of invertebrate fossils as well as other natural history collections (Cato, 1991; Simmons, 1993; Simmons, 1995).

Molecular work on ostracodes has thus far either used allozyme-based or DNA-based techniques. The application of allozyme-based methods has provided numerous data on population genetics and reproductive modes in ostracodes. With this technique, it has also been possible to construct phylogenies, although these have been restricted to distance-based methods. With the usage of DNA-based methods, a new era in ostracode research has begun. It is now possible to obtain accurate estimates for genetic diversities at very fine scales, even within individuals. The DNA-based approach is also very useful for reconstructing evolutionary histories at different taxonomic levels. Within species, for example, phylogenies reveal past episodes of dispersal and genetic exchange. Together with morphological data, DNA sequence data can test for congruence of molecular and morphological evolution and variability. At high taxonomic levels, DNA sequence data provide information on mechanisms of evolution and speciation. This allows for testing whether a certain, morphological feature has evolved once or several times independently. By applying the principle of the molecular clock, DNA sequence data provide relative age estimates that can be calibrated against fossil data and be linked to past climatic or geological events.

The Lower Devonian Haragan Formation of Oklahoma has well preserved odontopleurid trilobites found in repeated calcarous mudstones. These layers (5–9cm. thick) represent distal tempestites that rapidly buried and preserved completely articulated odontopleurids which provide important paleobiological information. The genal and pleural spines of Leonaspis williamsi and Dicranurus hamatus elegantus of the Haragan Formation are examined and compared.

In Leonaspis the ventrally directed genal and pleural spines are straight and lay flat. The first pleural spine is the longest followed by progressively shorter pleural spines. Several collected and prepared enrolled specimens have the spines radiating outward. In an enrolled position the spines would protect Leonaspis from a large predator.

The pleural spines of Dicranurus have a very different pattern from Leonaspis. The first three spines are short and laterally directed, the fourth, sixth and seventh are very long, curved and directed ventrally, the eighth, ninth and pygidial spines are short and decrease in length toward the pygidium. There is no pleural spine on the fifth thoracic segment and the genal spine is very long and curved. On these spines at many growth stages there is direct and indirect evidence of being encrusted based on the following: (1) Epibionts such as bryozoans, brachiopods and a crinoid; 2) Endoliths (25–150 microns in diameter) of unknown origin are found all over Dicranurus but are predominantly on the spines; 3) Pyrite (now limonite) coating the spines apparently formed from the decay of organic matter. If the source of the organic matter came from the trilobite, then pyrite would be found all over Dicranurus. However, it is only found randomly on the spines. This pattern is like some of the encrusting bryozoans suggesting that the source of the organic matter may be from an encrusting organism.

It is doubtful that the pleural spines of Dicranurus would be adapted for resting on the bottom when bryozoans are found encrusting the entire surface of the spine. However, the very long pleural and genal spines with attched organisms would break up the outline of Dicraurus making it less conspicuous to a predator.

There were two major kinds of Pennsylvanian-age tropical swamps: coal swamps, represented by most coal seams, and clastic swamps, commonly associated with coal as roof shale or sandstone floras. Such environments were part of depositionally-complex lowlands that also included non-swamp habitats. In general, the Pennsylvanian-age coal and clastic swamps were dominated by non-seed (lower vascular, spore-producing) plants, and the mesic, non-swamp vegetation was characterized by seed-plant (pollen-producing) dominance. On occasion, some drier-site kinds of vegetation are preserved, providing a glimpse of other kinds of plants in the lowland regions of the tropical belt; among these are the earliest known conifers (Scott and Chaloner, 1983) in the Middle Pennsylvanian.

Coal is the most abundant fossil fuel resource, acting as a terrestrial carbon sink since the evolution of forests in the Late Devonian. Debate concerning its accumulation began centuries ago when naturalists ascribed its formation to catastrophism associated with the Genesis Flood. With empirical data derived from both modern peat accumulations and ancient coal deposits in the mid-to-late 19th Century, the general scientific community developed a set of criteria upon which to demonstrate the autochthonous (in situ) nature of most peat accumulations. At the same time, adherents to the teachings of Ellen G. White, the Seventh Day Adventist leader, and George McCready Price continued to propagate the idea that our global coal (and oil) reserves were the result of the Noachian Flood. In Price's model, adapted and changed by recent creationists, all continents were denuded by strong tidal activity inherent in the Flood waters. Rafts of floating vegetation were transported to ocean basins where they sank en masse, forming coal deposits, with subsequent burial by siliciclastics and limestones derived from the erosion of alternative source areas. The alternation of vegetation mats derived from one source area and sediments derived from another throughout the year of the Flood accounted for the stratigraphic sequence in coal-bearing strata.

Fusulinacea are an extinct superfamily of small to large, to very laurge, calcareous Foraminiferida. They were entirely marine sind made their first appearance near the end of Early Carboniferous time (Text-fig. 1). They thrived during Middle and Late Carboniferous and Permian time. During that 100 million year existence, they evolved more than 150 genera and more than 6000 species before starting a decline in the later part of the Permicm and finally becoming extinct near the end of that period. Members of the Fusulinacea became giants, typically reaching 1 cm or more in length, and some became enormous giants, reaching 4 and 5 cm in length in the mid-Permian, and a few as much as 10 cm! Not bad for a single celled organism. Fusulinaceans are usually large enough that field geologists can spot them quickly in their stratigraphic units.

Sponges or Porifera are among the most primitive and simplest of metazoan organisms and have a long geologic record, based largely on mineralized skeletal elements termed spicules. Spicules, then, are of interest to micropaleontologists, and their study and interpretation provide opportunities for wide-based research by researchers ranging from student beginners to professionals and for research throughout the geologic column and across the country. Much of the detailed geologic record of spicules is yet to be discovered.

Curiosity about the history of life on our planet is a major motivational force for earth scientists. Fossil organic compounds, the components of petroleum and sedimentary organic matter, record aspects of the evolution of the biosphere from as far back as 1.8 billion years and perhaps longer. Elucidation of this record is continually advancing as a result of the concerted interests and efforts of geologists, biologists and chemists. It is also aided by advances in technique and instrumentation. Fascinating new developments and insights abound. In this paper I review some early landmarks and discuss the recent progress made in organic geochemistry, particularly as it applies to biomarker research. The examples of recent work are heavily biased toward my own interests and are not intended to be comprehensive. Because the literature citations are also selective and rely heavily on reviews, readers are advised to seek out the primary literature for accurate detail of specific subjects.

The technique of freeing fossils from carbonate rocks by the use of various acids has been known for many years, but still is not used as widely as might be expected. Cooper and Whittington (1965) cited early uses of acid to prepare graptolites and eurypterids (Holm, 1890; 1898). Common practice among early paleontological users of acid was to pick up a silicified specimen, or carefully chip one out of the matrix by hammer and chisel, and use the acid to clean it or to expose internal features. For example, Waagen (1882, p.354) mentioned exposing the internal features of silicified brachiopods by use of “dilute acid” (kind unspecified) from Permian rocks in the Salt Range of India (now Pakistan).

Historically, the greatest freshwater bivalve species diversity in the world was in the Tennessee, Cumberland and Alabama River systems. The Tennessee River System had 94 and the Cumberland River System had 85 taxa reported (Starnes and Bogan, 1988). Ortmann (1918, 1924, 1925, 1926), Wilson and Clark (1914), Neel and Allen (1964), van der Schalie (1939, 1973) and van der Schalie and van der Schalie (1950) documented this diverse fauna. However, even in the early days of this century these authors noted the decline in the mussel populations and the loss of species from certain rivers (e.g. Ortmann, 1909a, 1918).

Speculation about the behavior and life activities of any kind of extinct animal seems to be a waste of time. But people are curious, and they do it all the time. Their favorite subjects, of course are dinosaurs. You don't have to be an expert and it doesn't cost any money. Anybody can do it. Did Diplodocus swim? Or just soak in those Mesozoic lakes and streams? Did Tyrannosaurus chase its prey, or did it just scavenge on left-overs? Did Mononykus burrow in the ground to hide its head, or did it just scratch its arm pits? It is obvious that it didn't fly, but it must have run fast. You don't have to be a paleontologist, or an ethologist. In fact, it is probably an advantage not to be a scientist at all. (How come? Then you're free to let your imagination run wild. That sure would help Mononykus.) The only equipment you need is a powerful imagination, some common sense, and a certain amount of evidence. That evidence will be the clues, the tips that stimulate your imagination–in this case, how a long-dead animal that lived many millions of years ago behaved. Let me show you how that works.

Why plants? – Why include plants in a course on dinosaurs? They don't move, lack large teeth and sharp claws, and are non-sentient. The average student (who can spell Deinonychus correctly) hasn't a clue to the genera of even the most common plants. However, without plants, dinosaurs (or any other heterotroph) would not exist. Plants are the basis for global life, trapping the sun's energy in a form useful to consumers. Thus, the photosynthetic efficiency, palatability, and digestibility of plants define the total energy in the system available for use by consumers – and therefore the total biomass of consumers. Additionally, the morphology of individual plants determines the “packages” of food available to herbivores, and in the aggregate, the three-dimensional environment in which the herbivores and their carnivores live.