The Dung File consists of a list of references dealing
with pollen, parasites,
and plant remains in coprolites and latrine fills from
archaeological and palaeoenvironmental
sites. The focus is on studies in North America. The Dung
File is subdivided into ten sections: four
depend on the origin of the deposits being investigated (Part 1: Mostly Human,
Part 2: Mainly Mammal, Part 3:
Animal Middens, Part 4: Other
Critters), there are two
broader categories, Part 5: General and
Review Articles,
Part 6: Field and Laboratory Methods,
one focussed on theses, Part 7: Theses,
and two focussed on modern
comparative studies, Part 8: Comparative
Studies - Human and
Part 9: Comparative Studies - Mammal.
Finally, there are a number of
articles from news magazines and the popular
press (Part 10: Popular Press and
Commentary) and some less readily available items listed in
Part 11: Conference Abstracts and Grey
Literature.
The call numbers are for the library system at the University of
Alberta. The
remarks in green are my comments.
Part 3: Animal Middens: Packrat, Woodrat,
Stick-nest rat, and
Hyrax
- Betancourt, J. L., and T. R. Van Devender
1981
- Holocene Vegetation in Chaco Canyon, New Mexico.
Science 214(Number 4521, 6 November 1981):656-658
.
AEU SCI Q 1 S41 Examined macros from
packrat
middens from north side (drier side) of Chaco Canyon. Reports 24
C14 dates on material from middens, from 22 middens.
Dates span 10,600 to 460 C14 yr BP. Identified 78
plant
taxa from middens, representing about 25% of modern flora. Early
Holocene middens contained Douglas fir (Pseudotsuga
menziesii), Rocky Mountain juniper (Juniperus
scopulorum), and limber pine (Pinus cf.
flexilis)
remains, indicating cooler and moister than present conditions.
Consider these to be relicts of more extensive late Pleistocene
conifer-dominated woodland. Mid-Holocene samples suggest pinyon-
juniper woodland (Pinus edulis, Colorado pinyon). After
5500
yr BP, suggest conditions became more xeric. Youngest sample (460
yr BP) lacks pinyon and juniper but assemblage looks close to
that
from modern vegetation near the site - most taxa (87%) occur
within
30 m of site. Dominated by four-winged saltbush (Atriplex
canescens), cliffrose (Cowania mexicana), and Mormon
tea
(Ephedra torreyana). Probably resembled modern desert
scrub,
with a few juniper and pinyon-juniper stands in favoured locales.
Records document expansion of ponderosa pine (Pinus
ponderosa) in mid-Holocene, associated with greater summer
rainfall (summer monsoon). [Note: seems to contradict suggestion
of
more xeric mid-Holocene conditions made earlier.] Do not feel
that
climate change can explain reduction in pinyon and juniper in
late
Holocene, after about 1230 yr BP. More likely due to human impact
(e.g., firewood gathering), especially reflecting increased local
populations. (19/04/2009).
- Betancourt, J. L., T. R. Van Devender, and
P.
S. Martin (editors) 1990
-
Packrat Middens: The Last 40,000 Years of Biotic Change.
University of Arizona Press, Tucson, Arizona, USA vii + 467
pages
.
AEU SCI QE 720 P119 Twenty-one papers, most
focussed on studies in North America, but four from middens
elsewhere. Papers are listed and discussed individually elsewhere
in The Dung File. (30/07/2009).
- Carrión, J. S., L. Scott, and J. C.
Vogel
1999
- Twentieth Century Changes in Montane Vegetation in the
Eastern
Free State, South Africa, Derived from Palynology of Hyrax Dung
Middens.
Journal of Quaternary Science 13:1-16
.
AEU SCI QE 696 J86 Reviews foraging and
life
behaviour of hyraxes (Procavia capensis) and previous
studies that show potential for long pollen sequences from hyrax
dung accumulations, which often occur in arid areas where other
pollen preservation sites are rare. remains are mainly from dung,
not from nesting materials, which are not collected by these
animals. Reviews local vegetation around the study site, a rock
shelter, Rooiberg Midden II, with a predominantly grassland area.
Used radiocarbon dating to assign ages to midden samples all from
20th century. [However, I don't follow the discussion of how it
was
possible to date these samples.] All samples contain exotic
pollen
types (such as Pinus and Eucalyptus) that are
probably derived from trees planted around homes in the nearby
town
of Clarens. Paper includes some LM and SEM images of some of the
palynomorphs in the samples. Generally the pollen spectra agree
with the local vegetation. However, the spectra include aquatic
pollen types, suggesting the hyraxes visited water pools, and
some
other types, such as fern spores, suggesting moist environments.
Various dung-related palynomorphs, especially fungal spores
(e.g.,
Sordariaceae, Chaetomium, Glomus, and others), and
endoparasite, Trichuris, eggs, also from dung origin.
Water-
related pollen types thought to be from drinking water from
springs, about 100 m away from the site, indicating wetter
conditions earlier in 20th century. Changes in relative abundance
of forest edge pollen types (Buddleja, probably
Buddleja
salviifolia, and Leucosidea, probably Leucosidea
sericea) and grassland types are related to occurrence of wet
and dry spells. Pollen changes are interpreted as reflecting
environmental changes, rather than hyrax diet changes [though
won't
these be linked?]. These changes are also related to land use,
especially grazing pressure and fuel gathering, and fire control.
(06/08/2005).
- Davis, O. K., and R. S. Anderson 1987
- Pollen in Packrat (Neotoma) Middens: Pollen Transport
and the Relationship of Pollen to Vegetation.
Palynology 11:185-198
.
AEU SCI QE 993 P18 Examined four types of
midden materials, from modern (present) middens, including
samples
of packrat faecal pellets. All samples from SW USA. Good pollen
recovery from midden material and well-preserved. Some pollen
probably from airborne sources, that is, beyond the foraging
range
of the packrats. However, airborne pollen types are present in
lower percentage in midden samples than in those of other sample
types. Large number of taxa recovered from samples (e.g., 28
types
in samples from Owl Canyon, Colorado). Faecal pellets contain a
greater proportion of pollen of zoophilous types than midden
samples. Some pollen probably arrives at the site through plant
material brought in by the packrats. Considerable pollen may
adhere
to plant material. Question if some pollen may be brought in on
fur
of packrats. Used these data to compare pollen spectra with
surrounding vegetation. Concluded that samples do represent local
vegetation variability although considerable variation between
small samples from within the same midden. Probably need to use
larger samples. Used these data to examine fossil packrat midden
samples from two sites (one each in Colorado and Arizona). Midden
samples vary in age from about 14,000 yr BP to almost present.
Samples from Organ Pipe Cactus National Monument (Arizona) show
transition from Late Pleistocene to Holocene, reflected in
reduction of pollen from pinyon-juniper woodland and increased
abundance of pollen from Sonoran Desert plants (many of which are
insect-pollinated, so shows local presence). At Owl Canyon
(Colorado), pollen shows probable arrival of pinyon pine only
within the last few hundred years. Note that they have analyzed
54
packrat middens. (21/07/2005).
- Davis, O. K., and R. S. Anderson 1988
- Pollen in Packrat (Neotoma) Middens: Pollen Transport
and the Relationship of Pollen to Vegetation: Reply.
Palynology 12:226-229
.
AEU SCI QE 993 P18 Refutes and disputes the
criticisms raised by Van Devender (1988) of their 1987 paper. In
particular, emphasises that sample to sample variability in
pollen
concentrations is important in interpretation of the assemblages.
Believe that this represents variable depositional processes.
Note
that macrofossil analyses are usually semi-quantitative and
difficult to relate to vegetation. Not all pollen from a taxon
necessarily from plants in immediate vicinity of midden, some
from
further sources. Notes that macros may also give misleading
impression of abundance of plants in local vegetation
(?collecting
bias by packrats). Disagree that pollen data may not provide
species level information, dependent partly on availability of
reference material. Pollen and macros should be seen as
complementary techniques. (21/07/2005).
- Elias, S. A., and T. R. Van Devender 1990
- Fossil Insect Evidence for Late Quaternary Climate Change in
the Big Bend Region, Chihuahuan Desert, Texas.
Quaternary Research 34:249-261
.
AEU SCI QE 696 Q24 Examined insect
assemblages from packrat middens at 5 localities (Baby Vulture
Den,
Ernst Tinaja, Maravillas Canyon, Terlingua, and Tunnel View).
Samples span >36,000 yr BP to present. Recovered 79 taxa from 23
families. Most identifications to species level (35) were from
beetles. 18 beetles are indicator taxa, either temperate
(grasslands) or desert indicators. Assemblages fall into two
zones:
earlier zone (25,000 - 12,000 yr BP) contains more temperate
taxa,
later zone (12,000 - present) contains more desert indicators,
after 2,500 yr BO the assemblage contains only desert taxa.
Discusses ecological implications of some specific taxa
(carabids,
dung beetles, spider beetles, darkling beetles, seed beetles, and
weevils). Environmental implications are a shift from a cooler,
moister conditions of Wisconsinan to hotter drier conditions
through the postglacial. Contains SEM images (p. 258) of some
taxa.
Discusses vegetation record from Maravillas Canyon and Rio Grande
Village region. Pattern is similar but vegetation changes seem
to
lag behind insect changes suggesting some plants (e.g., pinyon
pine) persisted after shift to more arid conditions.
(17/03/2002).
- Hadly, E. A. 1999
- Fidelity of Terrestrial Vertebrate Fossils to a Modern
Ecosystem.
Palaeogeography, Palaeoclimatology, Palaeoecology
149:389-
409
.
AEU SCI QE 500 P15 Lamar Cave, Wyoming, in
Yellowstone National Park. Attempt to see if fossil community
accurately reflects the living community. Used modern fauna of
YNP
as a comparison. Cave shows 16 stratigraphic levels, down to
bedrock. Samples recovered from pit in midst of deposit (no
archaeological materials). Most of deposit is woodrat midden
(Neotoma cinera). Lowest level dates to 2000 - 2800 yr BP.
Other contributors to deposit are carnivores (wolves and
coyotes);
ungulate bones (mainly distal limb bones) show carnivore damage.
Assemblage may be biased by collecting preferences of woodrats;
their remains constitute 11% of fauna (constant over time).
Collecting range of predators may also vary; deposits show
evidence
of prey deposited by both hawks (diurnal) and owls (nocturnal).
Pellets and scat are collected by the woodrats and brought to
cave.
Comparison with scats/pellets from modern samples shows cave
deposit is a composite and not dominated by any one carnivore
type.
Levels accumulated at different rates (300 years to 1400 years
for
lowest level). Shows that even already demarcated levels may span
considerable times. Hence, is it legitimate to consider all fauna
from one level as an assemblage? Assemblage from the cave shows
species richness more comparable to modern fauna than the scat
samples (carnivores are selective). Also, a greater chance of
encountering rare taxa with a time-averaged assemblage. Assumes
that assemblage represents area within about 5 km radius of site
(range of collecting agents). Considered as a whole, assemblage
shows 67% of (non-flying) species within YNP. Individual levels
may
be only 5% in contrast. But assemblage represents about 93% of
species from vegetation communities immediately around site.
Showed
that larger sample sizes result in greater number of taxa
identified. Mammals found that characterize the modern sagebrush
grassland (especially small mammals). These are abundant even in
small sample sizes, showing that an adequate characterization of
nearby habitats can be made even from small samples.
(14/04/2002).
- Hebda, R., B. G. Warner, and R. A. Cannings
1990
- Pollen, Plant Macrofossils, and Insects from Fossil Woodrat
(Neotoma cinerea) Middens in British Columbia.
Géographie physique et Quaternaire
44:227-234
.
AEU SCI G1 R452 Reports on results from two
sites in southcentral British Columbia. Oregon Jack Creek (e of
Lillooet) dated at 1150±80 yr BP (WAT-1764) and Bull Canyon
(w
of Williams Lake) dated at 700±80 yr BP (WAT-1765). Both
sites
in dry interior with Douglas fir an important vegetation
component.
Pollen samples dominated by AP (especially Cupressaceae -
Juniperus) but abundant NAP (especially Artemisia).
Pseudotsuga pollen seems under-represented with respect
to
abundance in present local vegetation and strong occurrence in
macrofossil assemblage. Macros are mainly from tree and shrub
taxa,
mostly from plants within about 50 m of midden sites. Abundant
Pseudotsuga menziesii, Juniperus scopulorum and
Artemisia. Beetle remains (4 genera) recovered from OJC
midden. Pollen assemblage shows better presentation of dry
habitat
taxa than usually found in lake core samples. Authors conclude
that
woodrat midden research has considerable potential in this area.
Paper contains some useful SEM images of macrofossils (including
Lappula).
- Jackson, S. T., J. L. Betancourt, M. E.
Lyford,
S. T. Gray, and K. A. Rylander 2005
- A 40,000-year Woodrat-midden Record of Vegatational and
Biogeographical Dynamics in North-eastern Utah, USA.
Journal of Biogeography 32:1085-1106
.
AEU SCI G 1 J855 Sites on north side of
Uinta
Mountains, on Utah/Wyoming border, at Dutch John Mountain.
Present
vegetation is woodland characterized by pinyon pine (Pinus
edulis) and juniper (Juniperus osteosperma). Sixty
midden sites examined; twenty-six also examined for pollen, and
48
dated. Dates spanned 375 to 35,170 C14 yr BP. Dates fall into
three
groups: Wisconsinan, late Pleistocene/early Holocene, and
mid-late
Holocene. Wisconsinan middens (4) had fewest taxa but was
dominated
by macros representing montane conifers, predominantly Pinus
flexilis, Juniperus communis, and Pseudotsuga
menziesii. Most plants grow at higher elevations today. Late
glacial samples (8) show greatest number of taxa. Greater number
and variety of shrub and woody taxa. Indicative of moister
conditions. Vegetation represents juniper woodland, with
indications of warmer and drier conditions just prior to the
Holocene, signalled by occurrence of Juniperus osteosperma
macros. Holocene group (33 middens) are characterized by
Juniperus osteosperma. Some species from the late glacial
disappear and new taxa (notably cactus, Opuntia) occur,
reflecting a drying trend. Pinyon macros appear after 775 yr BP
and
Ephedra viridis after 500 yr BP. Both trends in these taxa
also appear in the pollen data. Pinyon does not occur much
further
north than Dutch John Mountain, implying it is near its current
range limit. Data provide evidence of plant migration history.
Paper concludes with a lengthy and useful discussion of regional
vegetational and climatic history in the light of these findings,
including a summary for individual species (Pseudotsuga
menziesii, Pinus flexilis, Juniperus
scopulorum,
Picea pungens, and Juniperus horizontalis). Notes
that not all climate trends are apparent in the midden record.
For
example, the cold Younger Dryas interval is not evident here.
(17/06/2006).
- Jennings, S. A., and D. L. Elliott-Fiske 1993
- Packrat Midden Evidence of Late Quaternary Vegetation Change
in
the White Mountains, California-Nevada.
Quaternary Research 39:214-221
.
AEU SCI QE 696 Q24 Extracted plant
macroremains from eight middens from six sites. Span the range
from
about 19,000 - 2000 yr BP. None of the plant taxa recovered from
the oldest midden are present in area today. Assemblage is
dominated by Juniperus osteosperma (Utah juniper). This
indicates a depression of 600 m of woodland's lower boundary. By
early Holocene, midden yielded more shrub and desert taxa,
similar
to those in area today, and Pinus monophylla (singleleaf
pinyon pine). Youngest midden contains more xeric taxa. Holocene
samples are more similar to each other and to present vegetation
than to the Late Pleistocene sample. Results of stable isotope
(deuterium) values may indicate that warmer conditions were
prevalent by early Holocene.
- Nowak, C. L., R. S. Nowak, R. J. Tausch, and
P.
E. Wigand 1994
- A 30 000 Year Record of Vegetation Dynamics at a Semi-arid
Locale in the Great Basin.
Journal of Vegetation Science 5:579-590
.
Collected samples from a restricted area
in
order to assess local-scale changes. 20 midden samples, spanning
30,000 - 1,000 yr BP. Study shows that many taxa have occupied
the
areas continuously for most of this interval. Painted Hills site,
in Virginia Mountains, northwest Nevada. Main site (18 samples)
spanned 26,000 yrs. Obtained 20 C14 dates for
chronologic control. Main tree taxon (Juniperus
osteosperma)
appears throughout the record and is still present in the area
today. Similarly, most shrub taxa also appear throughout the
record
and are present in the area today, although a few taxa have
distributions that at present are at higher elevations than the
site. There is a similar pattern for graminoids and herbs, but
herb
taxa show a greater proportion of taxa that are not present in
the
area today. In addition, several taxa were found in the area
after
an exceptionally wet year (following a prolonged drought) and
were
not found in the fossil record. Suggests that drought may be an
important control. Statistical examination of the data shows that
there were significant changes at the Pleistocene/Holocene
transition and also in the Late Pleistocene (20,000 - 30,000 year
interval). Site is within 0.5 km of Lake Lahontan's highstand and
can be tied to changes documented by lake levels. Changes in taxa
in middens reflect mesic-xeric intervals. Cooler and moister
conditions reflected in more mesic taxa. Late glacial and early
Holocene saw the greatest diversity of arboreal taxa (trees and
shrubs). Dramatic drop in Lake Lahontan signals change to drier
conditions in the Late Pleistocene. Also reflected in plant taxa.
Modern vegetation appears to have become established from the
mid-
Holocene onwards, showing prolonged interval of relative
stability.
Changes are not so dramatic as those seen in other areas, perhaps
because of topographic diversity (and hence abundance of
microhabitats). May also represent high genetic diversity within
species, allowing tolerance of variety of conditions (genetic
plasticity). Species appear to have remained in place despite
significant climate change. This forms a contrast with other
areas
and leads to some significant questions as to why the difference.
(02/07/2006).
- Pearson, S. 1999
- Late Holocene Biological Records from the Middens of
Stick-Nest
Rats in the Central Australian Arid Zone.
Quaternary International 59:39-46
.
AEU SCI QE 696 Q229 Examines pollen from
stick-nest rat (Leporillus apicalis and Leporillus
conditor - now extinct in Australia) middens. Middens are
prevalent in caves and rock shelters in arid areas and most are
less than 3000 years old (older middens found in the Flinders
Range). Compared pollen spectra from middens with modern pollen
spectra. Most data (117 samples) reported from a midden at
Umbeara
Station (Northern Territory). Spectra dominated by shrub and forb
pollen. Scats contained large amounts of perennial shrub pollen.
Stratigraphy in middens may be complex; layers may be mixed.
Interpretations of ecological change need to be cautious because
of
coarse temporal resolution of midden samples. Potential as
sources
of palaeoecological information may be limited.
- Scott, L. 1989
- Pollen Analysis and Palaeoenvironmental Significance of
Quaternary Faecal Deposits in Africa.
In Environmental Quality, edited by E. Spanier, Y.
Steinberger and M. Luris, pp. 65-71. Environmental Quality and
Ecosystem Stability: Vol IV-B. ISEEQS Pub. Jerusalem,
Israel
.
Review article. Sites for pollen analysis
are rare in arid Africa. Animal middens can yield
palaeoenvironmental information. Hyrax (Procavia) are
widespread and their midden accumulations, held together by dried
urine in arid environments, include plant material and faecal
pellets. Plant material can be used for C14 dating. Some midden
deposits date to mid-Holocene. Midden deposits show previously
moister conditions in some areas and also impact of recent
pastoral
and agricultural practices. Midden-derived pollen spectra appear
to
be a good reflection of surrounding vegetation, as indicated by
modern samples. Dassie rats (Petromus) only live in Namib
desert and therefore their middens have more limited potential.
Hyaena coprolites from caves have also been analyzed for pollen
-
mostly brown hyaena (Hyaena brunnii) in southern Africa,
striped hyaena (Hyaena hyaena) in northern Africa and
Middle
East. Tend to yield small amounts of pollen, perhaps because of
oxidation (or diet??). Possible that bat guano may be useful and
yield pollen too. (11/05/2002).
- Scott, L. 1994
- Palynology of Late Pleistocene Hyrax Middens, Southwestern
Cape
Province, South Africa: A Preliminary Report.
Historical Biology 9:71-81
.
Middens from hyrax (Procavia
capensis) found in Pakhuis Pass, Cedarberg Range, now
occupied
by fynbos vegetation (xeric shrubs, succulents and ericoids).
Middens found in a cave site, which may also have been occupied
by
people in the past (thus possibly explaining gaps in the midden
record). Seven middens yielded 16 pollen samples and 15
C14 samples, and 2 samples for macros. Also modern
samples from region were analyzed. Middens span 19,700 years to
1,270 yr BP, with gaps between 13,000 - 8,200 and 4,700 - 1,700
yr
BP. Midden pollen spectra show two zones. Zone A (older than
14,000
yr BP) shows LGM vegetation with more ericoid and Stoebe-
type pollen, possibly reflecting cooler conditions. Zone B, since
13,000 yr BP, has more woody and succulent pollen types. Increase
in AP may reflect slightly warmer climate after LGM. Moisture
conditions are more difficult to deduce. Mixture of plant types
may
indicate changing seasonality, with more even moisture
distribution. Modern pollen spectra show very little AP. Implies
region had more woody vegetation in Holocene than at present
Results suggest type of fynbos vegetation has been present since
LGM. (03/09/2006).
- Scott, L. 1994
- Past Vegetation Changes in Mountainous Areas in South Africa
as
Revealed by Pollen Analysis of Hyrax Middens.
In Proceeding of the XIIIth Plenary Meeting AETFAT, Malawi,
Vol. 2, edited by J. H. Seyani and A. C. Chikuni, pp. 1007-
1014
.
Looked at three sets of hyrax
(Procavia sp.) middens for pollen. Clarens midden (spans
last 30 years) from a grassland area. Pollen spectra here show
marked fluctuations in AP/NAP, probably related to variable woody
vegetation from stock grazing and town development with possibly
a
rainfall signal, reflecting rapid recovery of understorey
vegetation in relatively wet years. Two middens near Blydefontein
in semi-arid karoo are 300 and 1200 years old. Both show
reduction
in grass and increase in shrubby vegetation in last 300 years,
suggesting increased aridity and temperatures. Record appears in
agreement with 18O-derived temperature estimates from
stalagmites in Cango Caves. Finally, investigated a hyrax midden
at
Pakhuis Pass, Cedarberg, in fynbos vegetation area, dated 19,700
years old (oldest midden identified in Africa so far). Compared
pollen spectra with those from two modern hyrax midden samples
from
the same area. Midden spectra show more similarity to spectra
from
higher elevation sites, suggesting cooler dry conditions in last
glacial. (03/09/2006).
- Scott, L., and C. B. Bousman 1990
- Palynological Analysis of Hyrax Middens from Southern Africa.
Palaeogeography, Palaeoclimatology, Palaeoecology 7:367-
379
.
AEU SCI QE 500 P15 Hyrax (Procavia)
middens are primarily dung accumulations, consolidated with dried
urine (unlike packrat middens, which are mostly collected nest
material). Pollen in hyrax middens probably from pollen rain and
perhaps some diet additions. Two hyrax middens sampled from semi-
arid Karoo region, near Neupoort, at Blydefontein Basin. Research
associated with Later Stone Age archaeology project, focused on
Meerkat Shelter. Meerkat midden may span 300 years, and
Oppermanskop midden up to 1130 years, based on C-14 dates. Six
surface samples collected for comparison. Pollen assemblages
dominated by NAP, especially Gramineae and Compositae, However,
grass pollen appears reduced in upper midden levels compared to
Compositae and Chenopodiaceae pollen. Pollen record also obtained
from alluvial sequence at Upper .
- Scott, L., and B. Cooremans 1992
- Pollen in Recent Procavia (Hyrax), Petromus
(Dassie Rat) and Bird Dung in South Africa.
Journal of Biogeography 19:205-215
.
AEU SCI G 1 J855 Compared pollen
assemblages
from midden samples with those from surface samples from various
vegetation zones in South Africa, mostly distinguished on the
basis
of varying aridity. Examined 23 Procavia dung samples, 4
Petromus dung samples, 1 bird guano sample, and 21 modern
surface samples. Appears that most dung samples may be from
contemporary (active) middens, rather than ancient ones, though
the
age of the samples is not discussed and this point is not clear.
Pollen spectrum from the bird guano is very different and
distinct,
with large amounts of Poaceae pollen. This may be because the
sample is old or because the birds (types unknown) are making use
of different vegetation zones. Used factor analysis and
multidimensional scaling to compare dung and modern samples.
Although a few outliers, the dung and modern samples from the
same
vegetation zones group together closely, reflecting the modern
vegetation. Concluded that dietary preferences of the animals is
not a major factor in influencing pollen spectra, i.e., the dung
samples are good indicators of contemporary vegetation.
(08/04/2007).
- Scott, L., and J. Vogel 1992
- Short-term Changes of Climate and Vegetation Revealed by
Pollen
Analysis of Hyrax Dung in South Africa.
Review of Palaeobotany and Palynology 74:283-291
.
AEU SCI QE 901 R45 Examined pollen from
modern hyrax midden near Clarens, at Rooiberg Shelter I, 16
samples
from midden in total. "Bomb" C-14 (from atmospheric nuclear
weapons
tests) used to calibrate samples to provide an estimate of age.
Determined that lowest level sample started accumulating in 1962-
1963. Also examined changing extent of woody vegetation on slopes
around midden through air photos. Both agree in showing increased
amounts of woody vegetation. Changes may be related to rainfall
or
grazing (i.e., decreased grass and more shrubs). Short-term
changes
in rainfall appear to be reflected in midden record, implying
that
such records may be useful for interpreting similar changes in
the
more distant past. (14/04/2007).
- Smith, F. A., and J. L. Betancourt 2003
- The Effect of Holocene Temperature Fluctuations on the
Evolution and Ecology of Neotoma (Woodrats) in Idaho and
Northwestern Utah.
Quaternary Research 59:160-171
.
AEU SCI QE 696 Q24 Uses faecal pellet size
to
estimate body size of bushy-tailed woodrats (Neotoma
cinerea) from five middens. Middens are mainly mid to late
Holocene in age, though one extends to around 11,000 yr BP.
Pellet
sizes compared to modern samples from N. cinerea and N.
lepida (desert woodrat). In modern populations, body mass
then
correlated to temperature, with larger body mass correlated to
cooler temperatures. These data then used to investigate Holocene
data. Infers a distinct thermal forcing in past populations,
possibly in response to possible heat stress. Adult woodrats are
territorial and do not move far from "home" sites. Juveniles
disperse to find new locales. Inferred pattern of temperature
changes match well with those derived from nearby tree ring
records. Consider that this analytical approach can yield
valuable
data, especially on a decadal scale, one that is often not
captured
by other types of proxy data.
- Smith, F. A., J. L. Betancourt, and J. H.
Brown
1995
- Evolution in Body Size in the Woodrat Over the Past 25,000
Years of Climate Change.
Science 270:2012-2014
.
AEU SCI Q 1 S41 Investigating whether body
size of woodrats has changed in response to climate change
(larger
size -> heat conservation -> colder climate). Used faecal pellet
sizes as a surrogate for body size. Assume that faecal pellet
widths should have decreased during and since deglaciation. Used
pellets from middens from locales inhabited by woodrat
(Neotoma
cinerea) in dry interior western US. Pellets were dated by
C14 either directly or by dates on associated
macrofossils. Method tested by checking with pellets from modern
individuals. Found the best relationship between body size and
July
(summer) temperature and strong relationship between body size
and
pellet size. Most complete postglacial data set from Fishmouth
Cave, Utah. Shows a good relationship - estimated body size
declined since last glacial event. "Corrected" data for
latitudinal
variation in other palaeo data sets in order to combine palaeo
data
from several sites to investigate body size variation. Combined
data sets show same pattern as that from Fishmouth Cave. These
data
suggest that changes in body size within populations happen quite
rapidly in response to temperature changes. Conclude that these
changes are due to population changes in place, rather than in-
migration of woodrats from other areas, because populations are
thought to be fairly sedentary. Note that need genetic studies
to
confirm this. (11/04/2009).
- Spaulding, W. G. 1990
- Comparison of Pollen and Macrofossil Based Reconstructions
of
Late Quaternary Vegetation in Western North America.
Review of Palaeobotany and Palynology 64:359-366
.
AEU SCI QE 901 R45 Article written partly
in
response to comments by Hall (1986). Comparison of data from
macrofossil assemblages from packrat (Neotoma spp.)
middens
and pollen records at two locales: Colorado Plateau middens and
Chuska Mountains pollen record (SW USA), and Mojave Desert
middens
and Tule Springs pollen record. For the first case, the late
glacial vegetation history involved shifts in main vegetation
zones
and compositional changes. Pollen reconstructions (for ca. 19,500
-
25,000 yr BP) show a shift in elevation of arboreal forest
downslope and consequent expansion of alpine vegetation with
limber
pine at higher elevations than ponderosa pine. Midden data show
some taxa (e.g., limber pine) extended to lower elevations than
pollen-based reconstructions suggest. In the second comparison,
focussing on the 14,500 - 8,000 yr BP interval, again the midden
data show some vegetation zones (e.g., juniper woodland) and some
taxa (e.g., limber pine) were more extensive. Middens are assumed
to report local occurrence of a species and, when the same taxon
appears in many middens, this suggests it may be widely
distributed. Notes that middens and pollen records are showing
data
on different scales. Also notes that differences between the data
types will increase when the records being compared are further
apart.
- Thompson, R. S., L. Benson, and E. M. Hattori
1986
- A Revised Chronology for the Last Pleistocene Lake Cycle in
the
Central Lahontan Basin.
Quaternary Research 25:1-9
.
AEU SCI QE 696 Q24 Presents radiocarbon
dates
from packrat middens below the highest level of Lake Lahontan,
hence providing limiting dates. Middens intact and hence never
inundated. Dated materials from middens that had macrofossil taxa
that no longer occur in the area. Dates obtained from
Juniperus cf. occidentalis remains (twigs, leaves).
Dates show Lake Lahontan dropped below level of middens by at
least
12,070 yr BP.
- Van Devender, T. R. 1988
- Pollen in Packrat (Neotoma) Middens: Pollen Transport
and the Relationship of Pollen and Vegetation: Discussion.
Palynology 12:221-229
.
AEU SCI QE 993 P18 Detailed point by point
criticism of Davis and Anderson's (1987) paper from the
perspective
of macrofossil analysis. Contends that pollen data may show
variation in local vegetation near the site, rather than regional
vegetation differences. Does not agree that small sample size and
sample variability are linked - thinks that conclusion of high
variability is not supported. Considers that the pollen and
macros
evidence should be compared for the fossil midden samples. Notes
that some taxa present as macros are not identified in pollen
spectra. Believes this is partly due to poorer taxonomic
resolution
of pollen compared to macros. Notes that some of the pollen
types,
especially for cactus, would include pollen from many different
species with different ecologic requirements. Considers that the
pollen data alone can be misleading and does not provide useful
palaeovegetational reconstructions. (21/07/2005).
- Van Devender, T. R., and J. I. Mead 1978
- Early Holocene and Late Pleistocene Amphibians and Reptiles
in
Sonoran Desert Packrat Middens.
Copeia 1978:464-475
.
AEU BARD QL 1 C78 Provides a taxonomic list
(with accession numbers and C14 dates) of faunal
remains
from packrat middens. Bones may be in packrat midden either
because
rats intentionally collect them (e.g., for construction
material),
or because they are remains of animals living in or near the
nests,
or because they were brought to caves by raptors. Includes data
on
22 middens with 31 C14 dates. Total of 31 taxa listed,
representing 27 species, with others identified at family or
genus
level. Families represented include: Bufonidae (Toads),
Pelobatidae
(Spadefoot Toads), Testudinidae (Tortoises), Gekkonidae (Geckos),
Iguanidae (Lizards, 9 records), Telidae (Whiptail Lizards),
Boidae
(Boas), Colubridae (Snakes, 10 records),Crotalidae (Vipers, 3
records), and Leptotyphlopidae (Thread Snakes). Notes that most
of
these taxa are found in the region today but in desert scrub
habitats. Plants from the packrat middens show considerable
vegetation change (e.g., from more mesic woodlands to desert
scrub)
whereas the herpetofauna has been more stable. A few taxa were
found only in Holocene samples. Shows that winters were probably
not colder than today in late Pleistocene, otherwise some of
these
taxa would not have been able to persist in the region through
the
full glacial. Unclear why some species are now only restricted
to
deserts, as discussed especially with reference to Uta
(Side-blotched Lizards). (01/08/2009).
- Van Devender, T. R., R. S. Thompson, and J.
L.
Betancourt 1987
- Vegetation History of the Deserts of Southwestern North
America: The Nature and Timing of the Late Wisconsin-Holocene
Transition.
In North America and Adjacent Oceans During the Last
Deglaciation, edited by W. F. Ruddiman and H. E. Wright Jr,
pp.
323-352. The Geology of North America Volume K-3. Geological
Society of North America, Boulder, Colorado, USA
.
This detailed review is based on research
on
plant macroremains from packrat middens. Many middens have been
recovered from full glacial time, as well as postglacial. Plant
macroremains indicate plant distribution changes related both to
temperature and precipitation variations. Many assemblages show
groupings of plant taxa unlike vegetation types today. Authors
consider that the evidence supports the Gleasonian view of
individualistic response of plant species to environmental
change.
Reference list is useful as a starting place for work on this
topic.
- Wells, P. V. 1966
- Late Pleistocene Vegetation and Degree of Pluvial Climatic
Change in the Chihuahuan Desert.
Science 153(No. 3739):970-975
.
AEU SCI Q 1 S41 Reports on newly-found
middens in Chihuahuan Desert of west Texas. Notes the floristic
peculiarities of the area at present with disjunct species on
adjacent mountains. Coniferous forests on peaks the Chihuahuan
Desert (Chisos Mountains) are similar to those of the southern
Rockies or northern Sierra Madre. How did these species get
there?
One possibility if migration across the now-desert lowlands
during
pluvial (= glacial) intervals of Pleistocene. Evidence from
packrat
middens shows that this did not happen, because the lowlands
remained relatively arid during this time, though still moister
than present. Remains from middens include Pinyon Pine (Pinus
centroides remota), Juniper (Juniperus pinchotii),
Algerita (Berberis trifolia), Live Oaks (Quercus
grisea and Quercus pungens) and Prickly Pear
(Opuntia
macrocentra). However, the middens also yield xerophytes
including Lechuguilla (Agave lecheguilla), Roundflower
Catclaw (Acacia roemeriana) and Sotol (Dasylirion
leiophyllum). Locations of middens at present are too arid
to
support woodlands. The presence of pinyon pine in middens
suggests
woodland was about 800 m lower than present in the pluvial.
Suggests that pinyon-juniper-oak woodland was probably continuous
in the lowlands, which would have displaced the desert shrub
vegetation or this vegetation may have continued to occur in a
few
restricted drier locales within woodlands. Basically, Wells is
suggesting a non-analogue vegetation type. He notes that at
present
some desert species are found at comparatively high elevations
within woodlands, on south-facing drier slopes. This is also
shown
by the mix of desert and woodland taxa in middens. The desert
vegetation may have become segregated relatively recently, as
indicated by one woodrat midden dated to about 4200
C14
yr BP. Fully glacial (ca 18,000 C14 yr BP)
midden
at higher elevation (1200 m) lacks Douglas Fir, Aspen, deciduous
Oak, Maple and Cypress, as does a second midden dated at 36,000
C14 yr BP. Indicates that xerophilous vegetation
probably extended to high elevations in full glacial times.
However, these more mesic taxa are found in the Chisos Mountains
now, so if they are not a remnant, then how did they get there?
Suggests that mesophytic species (e.g., Douglas fir) are either
a
remnant from the Tertiary flora (which seems unlikely) or are a
result of long-distance transport of propagules from other
isolated
occurrences. Proposes bird dispersal as the most likely mechanism
(following Darwin's ideas). (01/08/2009).
- Wells, P. V., and C. D. Jorgensen 1964
- Pleistocene Wood Rat Middens and Climatic Change in Mojave
Desert: A Record of Juniper Woodlands.
Science 143(No. 3611, March 13 1964):1171-1174
.
AEU SCI Q 1 S41 Reports on wood rat middens
in Frenchman Flat area of southern Nevada. Juniper (Juniperus
osteosperma) is not present in the area today, and of only
restricted occurrence on regional mountain ranges and uplands.
Juniper twigs and seeds from 9 wood rat middens gave
C14
dates spanning 7800 to 40,000 yr BP. Wood rats (Neotoma
lepida) are present in area today. Suggests juniper-pinyon
woodland was about 600 m lower during much of this interval.
Implies conditions likely less arid than present. This is a
classic
paper and one of the foundation papers of midden studies. Notes
the
climatic inferences from these studies, the localized collecting
by
the wood rats, and hence the importance of these macrofossil
records as a corrective to the regional pollen records.
(24/04/2009).
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