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Quaternary Wapsipinicon Local Fauna (Empty Fissure and Dutch Creek Fissure local faunules), Jones County, Iowa Principle investigator:
This project was founded by the Paleobiological Fund |
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Quaternary Wapsipinicon Local Fauna (Empty Fissure and Dutch Creek Fissure local faunules), Jones County, Iowa Principle investigator:
This project was founded by the Paleobiological Fund |
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The Site:
Wapsipinicon State Park (Jones County, Iowa) is located along the transition between the Southern Iowan Drift Plain and the Iowan Surface landform regions (Prior, 1991). Within the park, the Wapsipinicon River and Dutch Creek have exposed Silurian dolostones overlain by pre-Illinoian glacial drift (Prior, 1991). Dutch Creek valley is the dominant feature in the western portion of the park and it is along the east wall of this valley that Dutch Creek and Empty fissures are located. The fissures, which are members of a large fissure complex, are in a bedrock outcrop, adjacent (the fissure’s talus slopes blend at their bases) and directly across Dutch Creek valley from Horse Thief Cave, a well-known fossiliferous archaeological site (13JN8).
Dutch Creek Fissure contains 0.25-0.5 m3 of light, orangish-red, silty sediment that appears to be in situ. The fissure is roughly 20-25 cm wide, 100-150 cm deep, and 60 cm high. The matrix contains abundant fossils (one liter sampled from the talus slope contained 45 microtine teeth), including a diverse fauna (Table 1). Several taxa recovered from this small sample [the yellow-cheeked vole (Microtus xanthognathus), collared lemming (Dicrostonyx torquatus), northern bog lemming (Synaptomys borealis), and the heather or mountain vole (Phenacomys intermedius)] have modern geographic ranges that are far north of Jones County, Iowa.
As the name implies "Empty Fissure" is nearly devoid of sediment (relative to its large size), but 50-60 cm of dark, dense, organic-rich sediment is present. Empty Fissure is roughly 30-40 cm wide, 300 cm deep, and 200 cm high. Remains of a “modern” fauna, including the meadow vole (Microtus pennsylvanicus), prairie vole (M. ochrogaster), and the woodland vole (M. pinetorum), were recovered within a small sediment sample taken from Empty Fissure.
Goals of my Dissertation (including this project):
The paleoecological investigation of the Wapsipinicon local fauna will include the following: 1. Removal of sediment samples (defined above) from Dutch Creek and Empty fissures, (roughly 50-75 lbs. from Dutch Creek Fissure and 100-150 lbs. from Empty Fissure); 2. Processing of the matrix to concentrate paleontological material using the techniques outlined by Hibbard (1949); 3. Identification of mammals (Table 1) and plant macrofossils (if recovered) in each faunule to evaluate ecological conditions at the time of deposition; 4. Utilization of fluorine content to establish species contemporaneity and to chose specimens (from clusters of similar fluorine concentrations) for radiocarbon dating in cooperation with Dr. Kenneth Tankersley, Kent State University, Ohio; 5. Dating (AMS 14C) of non-analog species pairs as needed to confirm contemporaneity of those species and to establish the site's chronological position within the geologic record; 6. Qualitative comparison of the climatic signatures produced by mammals and plant macrofossils for paleoecological agreement within and between the Wapsipinicon faunules; 7. If late Wisconsinan in age, comparison of the community represented by the Dutch Creek faunule with other late Wisconsinan age local faunas in Iowa and the eastern United States as compiled in FAUNMAP (FAUNMAP working group, 1994) – to include DCA or cluster analysis if feasible; 8. Comparisons of mammalian biogeography from the Wapsipinicon and other Iowa local faunas to late Quaternary environmental fluctuations as recorded by FAUNMAP (1996); 9. Documentation of the biogeographic variation of selected species over the last 25,000 yr.; 10. Identify standards of schmelzmuster for species of Microtus now residing from the Rocky Mountains to the East Coast (M. longicaudus, M. montanus, M. pennsylvanicus, M. chrotorrhinus, M. pinetorum, and M. ochrogaster); 11. Identify geographic trends of schmelzmuster within the taxa; 12. Apply these standards to fossil teeth, including those in the Wapsipinicon local fauna, to increase the accuracy of their faunal lists; 13. Perform a cladistical analysis similar to that of von Koenigswald and Martin (1984) for the six species of Microtus using schmelzmuster; 14. Sample various populations within the modern geographic range of Microtus taxa to establish morphological (landmark) characters that can be used to distinguish species and create standards for each; 15. Use a statistically significant sample of > 30 specimens to establish the modern standard variation of each species; 16. Identify evolutionarily significant aspects of the m1 morphology; 17. Morphometrically analyze a sample of fossil Microtus teeth from the Wapsipinicon local fauna to increase the accuracy of its faunal list; and 18. Morphometrically analyze the Microtus teeth from other late Pleistocene faunas of Iowa and the surrounding area to increase the accuracy of their faunal lists.
Various extra-local species have been recovered from these two sites. Below are three specimens of Lemmus sibiricus that have been recovered (not to scale). Click here to see the modern
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Class Amphibia
Order Anura
Isolated vertebrae
Class Aves
Unknown bird
Class Reptilia
Order Testudines
Shell fragment
Order Squamata
Suborder Serpentes
several morphotypes (vertebrae)
Class Mammalia
Order Marsupialia
Family Didelphidae
Didelphis virginiana
Order Insectivora
Family Soricidae
Blarina brevicauda
(Short-tail shrew)
Soricidae sp.
Cryptotis parva (Least
shrew)
Family Talpidae
Scalopus aquaticus
(Eastern mole)
Order Chiroptera
Family Verspertilionidae
Myotis sp.
(Plain nose bat)
Order Lagomorpha
Family Leporidae
Sylvilagus sp.
(Cottontail)
?Lepus sp.
Order Rodentia
Family Sciuridae
Tamias sp.
Sciurus sp.
Spermophilus cf.
S.
tridecemlineatus (Thirteen-lined ground squirrel)
Tamiasciurus hudsonicus
(Red or Pine squirrel) *
Marmota cf. M.
monax (“Marmot”)
Glaucomys sp. (Flying
squirrel)
Eutamias sp.
Other large ground squirrel
Family Geomyidae
Geomys bursarius (Plains
pocket gopher)
Thomomys talpoides (Northern
pocket gopher) *
Family Cricetidae
Peromyscus sp. (“Deer
mouse”)
Microtus ochrogaster
(Prairie vole)
M. pinetorum
(Woodland vole)
M. pennsylvanicus
(Meadow vole)
M. xanthognathus
(Yellow-cheeked vole) *
M. cf. M. miurus
(Singing
vole) *
M. cf. M. chrotorrhinus
(Yellow-nosed vole)
Synaptomys borealis
(Northern bog lemming) *
S. cooperi (Southern
bog lemming)
Clethrionomys gapperi
(Boreal red-back vole) *
Phenacomys intermedius
(Heather vole) *
Dicrostonyx sp. (Collard
lemming) *
Lemmus sibiricus
(Brown lemming) **
Family Muridae
Mus musculus (House
mouse)
Family Zapodidae
Zapus sp. (Jumping
mouse)
Order Carnivora
Family Mustelidae
Mustela sp.
(Weasel family)
Family Procyonidae
Procyon lotor
(Raccoon)
* Not present in Jones County, Iowa today.
** Southern most record of the genus. One of only three sites in U.S.
Click here (Smithsonian Mammal Species of the World) to find the modern ranges of most of these taxa.
Wallace, S.C., In Press, Schmelzmuster (enamel microstructure) and morphometric analyses of Microtus ochrogaster and M. pinetorum from the Wapsipinicon Local Fauna, Jones County, Iowa: Journal of Vertebrate Paleontology.
Wallace, S.C., 2008, Preliminary report on mammals of the Late Pleistocene Wapsipinicon Assemblage, Jones County, Iowa, pp. 105-121 in Farley, G.H., and Choate, J.R., eds., Unlocking The Unknown: Papers Honoring Dr. Richard J. Zakrzewski: Fort Hays Studies, Special Issue Number 2, 153 p.
Wallace, S.C., 2006, Differentiating Microtus xanthognathus and M. pennsylvanicus lower first molars using discriminant analysis of landmark data: Journal of Mammalogy, v. 87. no. 6, p. 1261-1269.
Semken, H.A., Jr., and Wallace, S.C., 2002, Key to Arvicolinae (Microtine) and Arvicoline-like first lower molars from the Late Quaternary of eastern North America: Journal of Archaeological Science, v. 29, no. 1, p. 23-31.
Wallace, S.C., 2001, Confirmation of Microtus montanus (mountain vole) from the late-Wisconsinan Jones Local Fauna, Meade Co., Kansas: Current Research in the Pleistocene, v. 18, p. 117-119.
Wallace, S.C., 2000, Four New AMS 14C Dates on Microtus xanthognathus with comments on Midwestern paleoecology: Current Research in the Pleistocene, v. 17, p. 138-139.
References cited:
FAUNMAP working group, 1994, FAUNMAP: a database documenting late Quaternary distributions of mammal species in the United States: Illinois State Museum Scientific Papers, v. 25, 690 p.
—— 1996, Spatial response of mammals to late quaternary environmental fluctuations: Science, v. 272, p. 1601-1606.
Hibbard, C.W., 1949, Techniques of collecting microvertebrate fossils: Contributions from the Museum of Paleontology, University of Michigan, v. 8, no. 2, p. 7-19.
Prior, J.C., 1991, Landforms of Iowa: Iowa City, University of Iowa Press, 153 p.
von Koenigswald, W., and Martin, L.D., 1984, Revision of fossil and recent Lemminae (Rodentia, Mammalia): Special Publications of the Museum of Natural History, v. 9, p. 122-137.