Douglas Burbank
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Oregon Miocene Fruits & Seeds

  A collection of 15 specimens of fruits and seeds containing Vitis (grape), Zanthoxylum (Szechuan Peppercorn/Yellow wood), Allophyllus and perhaps a Walnut/Hickory type thing, among others, has been given to me. The preservation is not great, and I suspect several specimens are just not identifiable. However, the locality and age data are quite good, and the Allophylus and Zanthoxylum, while present in the Eocene of Oregon, are absent in the present day, so the record may provide a modern limit to their occurrence in the area.
     The Project: a) Photograph all the culprits (light photography) b) SEM those specimens which warrant such treatment to see if they yield characters. c) Describe the fossils in detail. d) Make further identifications as necessary (decide if the Walnut/Hickory thing really is one or the other... or unidentifiable. e) Check literature on the geology of the area & write a brief "geological setting". f) Check literature on leaf floras from western North America to see if the Zanthoxylum & Allophylus records are indeed the youngest reports of these genera (they certainly are among fruits & seeds). - Publish in Oregon Geology?
 


Nevada Miocene Wood

  Describe a suite (? 5-7 different species) of fossil woods from NW Nevada. The woods are silicified. They were collected as "float" (not in place or associated with in-situ trunks) from an area rich in vertebrate fossils. There are two fossil faunas in the immediate area, which provide "age control" for the woods. There is a fossil leaf flora 40-50 miles to the west which gives some idea of the flora, although not at the same level.
     The project: Section the woods (cut with diamond saw, grind to optical thin-ness) each wood in cross, tangential & radial section. Examine slides under compound microscope & tally characters on a tally sheet (Considerable literature exists on wood anatomy, so you would learn as you went how to identify the characters). Photograph the sections & characters as you collect them. Then put the characters into a computer program which will return to you the closest matches. Check the fossils against examples of the "close matches". Photograph matches as necessary.
     The paper would include a summary of the woods & their identification, and an assembly of the wood data, vertebrate data & scrappy paleobotanical data into a reconstruction of the Miocene vegetation of NW Nevada. Possible submission place - Madrono.
 


Brandon Rehderodendron (Styracaceae)

  Describe a large (about 6 cm ) fruit from the Early Miocene of the Brandon Lignite, Vermont. The Project: a) Measure & describe the fossil, but anatomy & morphology. No SEM here, this will likely be all light microscopy. b) See if my impression that this thing is Styracaceae is right. If so, then c) Describe the fruits of the living species (I have all the necessary data, although much of it is in literature, and a good load of comparative modern fruits). d) Place the one other described fossil (auf Deutsch) into the context of the data accumulated. e) Sort it all out & decide on relationships.
     The sticky point here is that the fossil is similar to living Rehderodendron, but differs in some respects. The same is true of a fossil Rehderodendron from Europe. I would need to translate from the German on the European material. The rest would be fairly straightforward description and photography, perhaps involving some but not a lot of SEM work. The sticky point about this project is that I am not 100% certain that the fossil belongs in Rehderodendron. It might be a related extinct genus. This means I would have to be intimately involved in the project at all levels in order to make the call as to what I really think this things is. Nothing wrong with that, but just a slightly more complex problem.
 


Weaverville Flora, California

  H. MacGinitie described a ? Miocene leaf flora from Weaverville, California, but re-examination of the flora reveals a good possibility that it hosts a diverse fruit and seed flora as well. This needs exploration. At the very least, there are diverse remains of a species of Trapa which require description and comparison with species of Trapa described from other localities in North America, and with the living species of the Old World.
 


Novotony Flora

  Describe an about 10 taxon petrified fruit flora from the Eocene of Wyoming. Specimens need to be obtained (they are in Massachusetts now). They are clear silica, so little cellular detail is evident, but the morphology is good. This may involve some fancy literature work to sort out. It is not hard, but would require working with unfamiliar material & probably take a while to "come up to speed".
     Essence: Largely a literature research effort.
 


Sand Draw Flora

  Describe, photograph & write up an approximately 20-entity fossil flora. Fossils = casts & molds. All based on external morphology. You have done some of this with the Mastixia work. Requires literature chasing on each taxon similar to Novotony. Again, most of the Taxa are Old World tropics. A fairly significant project - If you had the full 6 months free, you could almost certainly kill it off, but if you are working, it might be hard to find the time.
     Essence: Largely a literature research effort, but with some interesting problems in interpretation "negative" morphology.
 


Nearest Living Relative Method

  Thought experiment. This is a Bruce project (it could use some purely scutwork computer help, but it really would not give you much chance to do anything really "on your own". It involves finding the present day ranges of taxa that lived in the Eocene in both the Old and New Worlds, then plotting the ranges of these taxa on a common map & creating a density map (contour map) of their occurrences. I know from previous work that the answer is that all these taxa pretty much clump in one area of SE Asia & SE North America, making the point that, by and large, these taxa have retained the same climatic tolerances through the last roughly 35 Ma. Half done.
 


Prodromous to La Porte

  The most diverse and well-preserved of the northern Sierra floras is from a mine at La Porte, California. This is easily a Ph.D. thesis if not more worth of material, involving a full description of the flora and its affinities.
 


LaPorte Paleoecology

  In addition to a systematic study, the La Porte flora affords the potential to undertake a very interesting paleoecological study. The site includes several superimposed beds of plant detritus, each of which extends for over 1000' feet. I have made collections of equal volume from several vertical transects along the face of the mine, which would allow one to compare the diversity and abundance of fossil material both along individual beds, and from bed to bed up the section.
     Recent taphonomic work with leaves has raised our awareness of how local a leaf flora can be in its "sampling" of the original community. The La Porte collections offer the opportunity to duplicate this work with fruits and seeds, to see if these more vagile structures also exhibit localization.
 


Dormancy

  An "idea" paper between Tiffney & K. Niklas. Premise. Dormancy of spores is not homologous w/ dormancy of seeds. Spores germinate & create gametophytes upon which sperm & egg are borne. Dormancy occurs between the production of the spore & the growth of the gametophyte. In seed plants, the spores go right through to maturity to create the pollen grain & the ovule, go through fertilization, and create a seed. Only then does dormancy come into play - between fertilization & establishment of the new plant. What influence does this transition have on the evolution of early land floras?
 


Gymnosperm Dispersal

  Susan Mazer (EEMB) and I wrote a paper on a careful statistical analysis of the correlation of dispersal mode to habit and diversity in angiosperms. A companion paper involving the dispersal modes of Gymnosperms is a very good candidate for a further research project. . The question is, does dispersal mode show correlation with habit (herb/shrub/tree) and diversity (# of species) in gymnosperms? The data base format is set up, and I have collected much data. This should be checked and the data base completed and then subjected to statistical analysis.
 


Cycad reproductive biology

  It is unclear (and of interest) to me how cycad reproductive biology works. How large does the female gametophyte get before fertilization, and thus how much does it "place a bet" on the reality of pollination before pollination occurs? Lotusland Botanic Garden has a huge collection of living cycads, as does one local cycad grower., Between them there is adequate material to sample across all of the genera of cycads, and to get multiple samples, to determine how this reproductive system works, and whether it varies between primitive and advanced members of the group.

 

 

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