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Quaternary Environments Quaternary Environments Non-Marine Biological Non-Marine Biological Evidence Evidence

Quaternary Environments Non-Marine Biological Evidence

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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

Macrofossil SeedsMacrofossil Seeds

Needle Cross SectionNeedle Cross Section

Macrofossil DiagramMacrofossil Diagram

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

Phytolith MorphologyPhytolith Morphology

Poaceae Zea luxuriens PhytolithPoaceae Zea luxuriens Phytolith

Poaceae Paspalum lividum PhytolithPoaceae Paspalum lividum Phytolith

Asteraceae Lipochaeta sp. PhytolithAsteraceae Lipochaeta sp. Phytolith

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

Wood AnatomyWood Anatomy

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

©Tom Kloster 2001: http://www.splintercat.org/JeffParkRidge/ParkRidgeImages/

©Tom Kloster 2001: http://www.splintercat.org/JeffParkRidge/ParkRidgeImages/

http://patti.tensegrity.net/album/moraine/display/trees.html

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

Treeline Fluctuations, SwedenTreeline Fluctuations, Sweden

Dahl and Nesje 1996

Vegetation Zones with ElevationVegetation Zones with Elevation

Vegetation Zones with ElevationVegetation Zones with Elevation

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

Packrat Midden Packrat Midden LocationsLocations

Davis: http://www.geo.arizona.edu/palynology/geos462/28packrats.html

Packrat MiddenPackrat Midden

Packrat MiddenPackrat Midden

Packrat Midden from University of Arizona (has Giant Sloth Bones)

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

Beetle MorphologyBeetle Morphology

Reconstructed Paleotemperature Reconstructed Paleotemperature Based on Insect Remains, UKBased on Insect Remains, UK

Mutual Climate RangeMutual Climate Range

Chironomid Percentage DiagramChironomid Percentage Diagram