Paleo EXAM 3

physiological controls on distributions of organisms and their traces

• groundwater profile

• meidum: grain size, density, saturation

• nutrients: type OM in water or sediment

• salinity

• hydrology: amount of freshwater input

• turbidity: water condition/circulation

• temperature

• oxygenation: based on circulation and OM content

marine ichnofacies are associations of recurring __ ___ and ____ facies

trace fossils

sedimentary

Who made marine ichnofacies

Adolf Seilacher

Teredolite ichnofacies

• occurs w coal swamps

• made by clams that bore into wood

medium controlled inchofacies

trypanties teredolites, glossifungities

Inchnofacies are named after particular traces but they dont have to be ____

present

glossifungites inchonfacies

traces are gravel/sand filled

burrows were filled/compacted

psilonichnus inchofacies

back shore deposits/lagoons

sandy/coastal beaches

skolithos ichnofacies

shifting sands

cruziana ichnofacies

sublittoral/deeper

on shelf

more mud/resources

Zoophycos ichnofacies

limited

slow sed rates

nereites ichnofacies

very limited

very slow sed rates

For ichnofacies, the overall coniditions control animals _____ that are there

behavior

As _____ decreases, organism ____ and ____ decreases. Burrow depth and mixing _____

Oxygen

diversity, abundnace

decreases

3 zones of tiering

Mixed zone, transitional zone, historical zone

Mixed zone

totally bioturbated by shallowest and deepest burrowing animals

all types of sediment processes

Transitional zone

bioturbated to varying degree

decreasing in % of bed disruption downward

Historical zone

No longer effeccted by sediment proccessing and disruption

Burrows help predict morphology of organism ____

body

____ ____(600-550 MA): glimpse into metazoan life of late ___-____

edicara Biota

Pre-cambrian

have to be ______ to make trace fossils

multicellular

trace fossil evidence preserves ___ ___

animal behavior

oldest trace fossils

1 Ga from India and 1.8-2 Ga from australia

Doushantuo formation embryos shows ___ ____

cell division

molecular clock evidence used to estimate dates of ___ ___ events

lineage splitting

____ _____is chemical associated with phylum found in rock samples

Biomarker evidence

biomarkers of ____, desmospongiae, found in rocks earlier than ____

sponges

edicarian

3 main groups of metazoan body plans

porifera, cnidaria, bilateria

Parazoans/the sponges body plan:

• groups of cells in ___ ___ separated by ___-____ material

• cells not organized into ____ or ____

• 2 layers, jelly-like

• organs, tissues

diploblastic animals

cnidaria and ctenophora

Disploblastic layers

• outer ectoderm

• inner endoderm

• separated by mesoglea

triploblastic animals

the remaining metazoans

triploblastic characterisitcs

3 layers of cells

• outer ectoderm

• middle mesoderm

• inner endoderm

Bilateral symmetry

Protostomes

• clevage

• coelom

• larva

• spiral, determinate

• schizocoelus

• trochophore larva (blastopore=mouth)

Dueterostomes

• clevage

• coelom

• larva

• radial, indeterminate

• enterocoelous

• dipleurula larva (blastopore=anus)

Protostomes 1: Spiralia/Lophotrochozoa

trochophore larva OR lophophore feeding apparatus

Protostomes 2: ecdysozoa

molt their exoskeleton as they grow

Dueterostomes: develop the ____ before developing the ____

anus

mouth

_____ from Newfoundland, fossil from precambrian

aspidella

Edicara Member: seires of ____ and ____ of pelagic to intertidal environments

siltstones

sandstones

Classification of edicara biota:

_____: concentric or radial (w or w/o symmetry)

____: without or with a head

radiata

bilateria

Charnwood forest

charnia masoni, edicara fossil

who made classification of edicara biota and why

Fendokin

considered it best not to force edicara biota into modern groups