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Quaternary EnvironmentsQuaternary EnvironmentsNon-Marine Biological EvidenceNon-Marine Biological Evidence
Proxy RecordsProxy Records
Macrofossil EvidenceMacrofossil Evidence PackratsPackrats Tree-line fluctuationTree-line fluctuation
Microfossil EvidenceMicrofossil Evidence PollenPollen
InsectsInsects
Macrofossil EvidenceMacrofossil Evidence
Quantitative analysis of Quaternary plant Quantitative analysis of Quaternary plant macrofossils began in 1957 (West 1957)macrofossils began in 1957 (West 1957)
Seeds, fruits (orchids to coconuts), cones, Seeds, fruits (orchids to coconuts), cones, sporangiasporangia
Leaves, needles, budsLeaves, needles, buds WoodWood
PaleoscatologyPaleoscatology
ScatScat Procedure Procedure
BlendBlendScreenScreen
Coprolites AnalysisCoprolites Analysis Can identify food sources and diseaseCan identify food sources and disease
CuticlesCuticles
Waxy coating that has distinct morphologyWaxy coating that has distinct morphology Stomata: control gas exchangeStomata: control gas exchange Trichomes (leaf hairs)Trichomes (leaf hairs) Cork cells (provide leaf support)Cork cells (provide leaf support) Silica cells (support, discourage foliavores)Silica cells (support, discourage foliavores)
PhytolithsPhytoliths Production
Silica is deposited in the secondary plant wall of some plants, particularly grasses and occasionally in wood.
Phytoliths most abundant in grasslands and steppes. Disperal
Large fragments move short distances (fragile) small fragments (silt sized) may be distributed by wind.
Preservation Resistant to oxidation, but the silica can be dissolved
by ground-water movement
PhytolithsPhytoliths
Identification Many plants don't produce phytoliths: only a partial
indication of plants in area Non-related species produce the same types :
dumbbells, saddles, bowls, boats, bottoms Some Taxonomic categories can be recognized:
panicoid, festucoid, chloroid A few forms are diagnostic to species level: e.g.,
maize
Phytolith MethodsPhytolith Methods
Oxidize sample (boil in HOxidize sample (boil in H22OO22)) Wet sieve (phytoliths silt size)Wet sieve (phytoliths silt size) Flotation (tetrabromoethane, ZnBr2) phytoliths Flotation (tetrabromoethane, ZnBr2) phytoliths
have specific gravity of 1.5-2.3, quartz 2.65have specific gravity of 1.5-2.3, quartz 2.65
Wood AnatomyWood Anatomy
Can identify wood to the species or genus Can identify wood to the species or genus levellevel Cell structureCell structure PitsPits TracheidsTracheids PoresPores Resin ductsResin ducts
TreelineTreeline
Upper TreelineUpper Treeline Temperature controlledTemperature controlled Dating wood from tree above current treelineDating wood from tree above current treeline Arctic brown paleosols beneath recent Arctic brown paleosols beneath recent
SpodosolsSpodosols Lower TreelineLower Treeline
Moisture controlledMoisture controlled Packrat MiddensPackrat Middens
KrummholzKrummholz
Prostrate stunted vegetationProstrate stunted vegetation Protected by snow packProtected by snow pack Can grow above present treelineCan grow above present treeline Technically a different genetic species of a plant Technically a different genetic species of a plant
that has stunted growth, but broadly used for that has stunted growth, but broadly used for environmentally stunted treesenvironmentally stunted trees
Flagged leaders standing out Flagged leaders standing out from a Krummholz mattfrom a Krummholz matt
Problems with Treeline StudiesProblems with Treeline Studies
Incomplete fossil record (highest elevation trees Incomplete fossil record (highest elevation trees may not have been found)may not have been found)
Elevation of mountain summits restrict how high Elevation of mountain summits restrict how high treeline could be recordedtreeline could be recorded
Present treeline is hard to determinePresent treeline is hard to determine Disturbances can affect tree line (fire, grazing, Disturbances can affect tree line (fire, grazing,
avalanches, wind abrasion, insects)avalanches, wind abrasion, insects) Lag time in response to climate changesLag time in response to climate changes
Advance faster than retreatAdvance faster than retreat
Treeline may be affected by isostatic upliftTreeline may be affected by isostatic uplift
Changes in Major Vegetation Zones for Changes in Major Vegetation Zones for 22,000 years in Nevada22,000 years in Nevada
Packrats (Neotoma)Packrats (Neotoma)
First used in Quaternary Paleoecology First used in Quaternary Paleoecology introduced by introduced by Phillip WellsPhillip Wells (Wells and (Wells and Jorgensen, 1964), a zoologist doing vegetation Jorgensen, 1964), a zoologist doing vegetation reconnaissance on the Nevada Test Site.reconnaissance on the Nevada Test Site.
Collect all vegetation around the middenCollect all vegetation around the midden Preserved by amberat (urine)Preserved by amberat (urine) Also bring in pollenAlso bring in pollen
Macrofossils and Pollen from Packrat Macrofossils and Pollen from Packrat MiddensMiddens
Davis: http://www.geo.arizona.edu/palynology/geos462/28packrats.html
Problems with PackratsProblems with Packrats
Collected material may not represent a random Collected material may not represent a random representation of surrounding environmentrepresentation of surrounding environment
Different species have different preferencesDifferent species have different preferences Discontinuous depositsDiscontinuous deposits BioturbationBioturbation
Creosote Distribution From Packrat MiddensCreosote Distribution From Packrat Middens
Davis: http://www.geo.arizona.edu/palynology/geos462/28packrats.html
Insect StudiesInsect Studies
Organisms usedOrganisms used Coleoptera (Beetles) most commonColeoptera (Beetles) most common Diptera (Flies)Diptera (Flies) Hymenoptera (Wasps and Ants)Hymenoptera (Wasps and Ants)
Found in sedimentary deposits such as lake Found in sedimentary deposits such as lake beds or peatbeds or peat
Based on exoskeleton morphologyBased on exoskeleton morphology Little lag in assemblage changesLittle lag in assemblage changes
InsectsInsects Study of late Quaternary beetle faunas began with Study of late Quaternary beetle faunas began with
J.V. Matthews (1975) North American J.V. Matthews (1975) North American G.R. Coope's (1977) study of British deposits G.R. Coope's (1977) study of British deposits S.A. Elias (1985) western U.S.S.A. Elias (1985) western U.S.
Production Production More species of beetles than of all other animals. More species of beetles than of all other animals.
DispersalDispersal Taphonomy poorly studied, but fossils are interpreted as local, Taphonomy poorly studied, but fossils are interpreted as local,
however, many beetles can fly and their remains are present in however, many beetles can fly and their remains are present in streams.streams.
Preservation Preservation Beetle carapaces are the most resistant of all insect fossils. Their Beetle carapaces are the most resistant of all insect fossils. Their
elytrae (chitinous wing covers) are particularly abundant, heads elytrae (chitinous wing covers) are particularly abundant, heads and legs also common.and legs also common.
IdentificationIdentification Beetles are probably the best studied insect group (taxonomically), Beetles are probably the best studied insect group (taxonomically),
and their preserved remains useful in identificationand their preserved remains useful in identification
Reconstructed Paleotemperature Reconstructed Paleotemperature Based on Insect Remains, UKBased on Insect Remains, UK