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The Last New Papersbender



Simpson, E.L., Hilbert-Wolf, H.L., Wizevich, M.C., Tindall, S.E., Fasinski,
B.R., Storm, L.P., and Needle, M.D. 2010. Predatory digging behavior by
dinosaurs. Geology 38(8):699-702. doi: 10.1130/G31019.1.

ABSTRACT: Minimal direct evidence exists in the rock record of dinosaurs and
mammals behaving as predators and prey, respectively. A newly discovered
Late Cretaceous trace fossil association of digging traces of maniraptoran
theropod dinosaurs and mammalian den complexes indicates a predator-prey
relationship. Three distinct associated trace fossils occur within a
floodplain siltstone-mudstone bed of the Upper Cretaceous Wahweap Formation
in southern Utah, United States. One trace fossil morphology and its
extramorphological variants record digging by a maniraptoran theropod
dinosaur, possibly a dromeosaurid or troodontid. The other two are
interpreted as mammalian den complexes. The proximal association of these
trace fossils suggests that dinosaurs used excavation techniques to prey on
mammals.




Wagensommer, A., Latiano, M., and Nicosia, U. 2010. First report of dinosaur
footprints from Madagascar: two tracksites from the Middle Jurassic Bemaraha
Formation. Ichnos 17(2):127-136. doi: 10.1080/10420941003659527.

ABSTRACT: Here we report the first record of tetrapod tracks from
Madagascar. We document two localities yielding dinosaur footprints, both
within the Middle Jurassic Bemaraha Formation (Morondava Basin) in western
Madagascar. The Sahalaly River tracksite yielded a single trackway belonging
to a quadrupedal dinosaur; probably a sauropod, but a closer determination
is hindered by bad preservation. In contrast, the Tsiandro tracksite yielded
numerous well-preserved theropod tracks that allow some inference about the
behavior of the trackmakers. 





Funston, P.J., Frank, L., Stephens, T., Davidson, Z., Loveridge, A.,
Macdonald, D.M., Durant, S., Packer, C., Mosser, A., and Ferreira, S.M.
2010. Substrate and species constraints on the use of track incidences to
estimate African large carnivore abundance. Journal of Zoology 281(1):56-65.
doi: 10.1111/j.1469-7998.2009.00682.x.

ABSTRACT: Population size and trends of large carnivores are difficult to
determine, but are often needed to inform conservation actions. Direct
counts maintained over long time periods are extremely difficult to achieve.
Indices of population sizes can be used to estimate large carnivore
abundances, but are often case-, species- and site-specific. Here, we test
the general applicability of track-based indices to estimate large carnivore
abundance. We surveyed 15 306.4 km of roads associated with 339 transects
across a wide geographical scale, large range of densities and variable
substrates for tracks of African large carnivores. A combined model for all
carnivore species on sandy soils serves as a robust approach to predict
large carnivore densities. Thus, indices based on track counts can provide
useful estimates of carnivore abundance. We found consistent relationships
between track densities and the actual carnivore densities, having taken
account of substrate.





Fritz, J., Hummel, J., Kienzle, E., Streich, W.J., and Clauss, M. 2010. To
chew or not to chew: fecal particle size in herbivorous reptiles and
mammals. Journal of Experimental Zoology. doi: 10.1002/jez.629.

ABSTRACT: A major difference between reptile and mammalian herbivores is
that the former do not masticate their food. Actually, food particle size
reduction by chewing is usually considered one of the adaptations
facilitating the higher metabolic rates of mammals. However, quantitative
comparisons of ingesta particle size between the clades have, to our
knowledge, not been performed so far. We measured mean fecal particle size
(MPS) in 79 captive individuals of 14 reptile herbivore species (tortoises,
lizards, and Corucia zebrata) by wet sieving and compared the results with a
mammalian dataset. MPS increased with body mass in both clades, but at a
significantly higher level in reptiles. Limited evidence in free-ranging and
captive individuals of Testudo hermanni indicates that in reptiles, the
ability to crop food and food particle size significantly influence fecal
particle size. The opportunistic observation of a drastic particle size
difference between stomach and intestinal contents corroborates findings
that in reptiles, in contrast to terrestrial mammals, significant ingesta
particle size reduction does occur in the gastrointestinal tract, most
likely owing to microbial action during very long ingesta retention. Whether
behavioral adaptations to controlling ingesta particle size, such as
deliberate small bite sizes, are adaptive strategies in reptiles remains to
be investigated.





Eronen, J.T., Puolamäki, K., Liu, L., Lintulaakso, K., Damuth, J., Janis,
C., and Fortelius, M. 2010. Precipitation and large herbivorous mammals I:
estimates from present-day communities. Evolutionary Ecology Research
12(2):217-233.

ABSTRACT: Question: How can mammalian community characteristics be used to
estimate regional precipitation?

Data: Global distribution data of large mammals and their ecomorphology;
global climate data.

Research methods: Non-linear regression-tree analysis and linear regression.

Conclusions: The methods unravelled the complex relationships between the
environment and the characteristics of mammalian communities. The regression
trees described here provide a reasonably accurate estimate of precipitation
values for today?s world. The strongest correlations are for annual
precipitation versus diet (R2 = 0.665), precipitation versus tooth crown
height (R2 = 0.658), and precipitation versus diet and tooth crown height
combined (R2 = 0.742)





Eronen, J.T., Puolamäki, K., Liu, L., Lintulaakso, K., Damuth, J., Janis,
C., and Fortelius, M. 2010. Precipitation and large herbivorous mammals II:
application to fossil data. Evolutionary Ecology Research 12(2):235-248.

ABSTRACT: Background: We developed a method to estimate precipitation using
mammalian ecomorphology, specifically the relative height of the molars of
herbivores (see companion paper, this issue).

Question: If we apply the new method to paleoenvironments, do the results
agree with previous results from fossil mammals and paleobotanical proxies?

Data: Large herbivorous fossil mammals of Eurasia. Data from NOW database
covers 23?22 Ma and is Eurasia-wide.

Method: We apply the new precipitation estimation method (based on
present-day mammalian ecomorphology) to fossil assemblages from different
localities.

Conclusions: The early Miocene retained the overall humid conditions of the
late Paleogene. A shift to more arid conditions began during the middle
Miocene. The late Miocene as a whole was a time of large changes, and there
was continent-wide restructuring of the distribution of environments. Our
new results agree with previous investigations and the mammal proxy data are
in good agreement with palaeovegetation data. Mammals and vegetation produce
similar precipitation values and large-scale patterns.




~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Jerry D. Harris
Director of Paleontology
Dixie State College
Science Building
225 South 700 East
St. George, UT  84770   USA
Phone: (435) 652-7758
Fax: (435) 656-4022
E-mail: jharris@dixie.edu
 and     dinogami@gmail.com
http://cactus.dixie.edu/jharris/


The way to a man's heart is through
his stomach.

                   -- old proverb


"The way to a man's heart is through
the fourth and fifth ribs."

                   -- Katchoo (and others)