Lecture 1: Introduction palaeontology
Palaeontology = the science of old/ancient beings.
Fossils = any evidence of past life
Taphonomy = from the moment a being dies to when it is fossilized and
found. Only a small proportion of the organisms (biocoenosis) are preserved.
Of which only a part is now exposed (thantocoenosisis). See diagram.
Kind of fossils:
- Body fossils: in amber (insects and spiders), ammonites, carboniferous plants, complete
skeletons, bones and teeth, feather imprints and soft tissue preservation.
- Trace fossils: crawling traces, footprints, trackways, coprolite (fossilized shit)
Fossil information hidden within
- Histology: e.g. tree rings
- Stable isotopes
- Molecular fossils (paleoproteomics): e.g. proteins say something about DNA, of which only
the last part of history has DNA preserved (1/2 million years and proteins 1 million years).
Use of fossils:
- Taxonomy: ordering and naming fossil groups.
o Eukaryotes: have a nucleus: animals, plants, fungi and protists
o Archeans: have no nucleus and a single cell membrane
o Bacteria: have no nucleus
Classification based on clades ( = a group consisting of an ancestor and all its descendants
(branch on the tree of life))
o Monophyletic group: consisting of all the descendants of a common ancestor
o Paraphyletic group: shared common ancestor, but not all the descendants included
o Polyphyletic group: grouped together, but do not share an immediate common
ancestor (homoplasy)
- Stratigraphy: erosion, transport, deposition.
Steno: principles of superposition, original horizontality, original lateral continuity and cross
cutting.
o Lithostratigraphy: defines lithological units on basis of observable rock characteristics
o Biostratigraphy: uses fossils in correlating lithostratigraphical units.
- Paleoenvironmental reconstruction: paleobiology, evolution, where do they live, what do
they eat etc. “the present is the key to the past”
, Geological time scale
Chronostratigraphic units: division of rock based on time (Upper and Lower)
Geochronologic units: division of time during which each chronostratigraphic units was formed (Early
and Late)
Lecture 2: Time, biodiversity and enviroment
An ideal GSSP would:
- Be accesible to research
- Be extensive enough to ensure future access
- Be easily related to other exposures worldwide
- Contain a radiometrically datable bed at the boundary
- Include well defined markers at the stage boundary that can be applied worldwide
Dating:
1. Biostratigraphy: relative age: FO en LO, index
fossils
2. Magnetostratigraphy: ~ abolute age: flipping
north and south pole
3. Radioistopes: abosolute age: natural radioactivity
preserved in sediment. If you know the ratio
between two isotopes, you know the age by use
of the half-life
4. Cyclostratigraphy: ~absolute age: eccentricity:
cycles vs ellips, obliquity: angle of earth and
precession: seasonality → insolation curve
Palaeontology = the science of old/ancient beings.
Fossils = any evidence of past life
Taphonomy = from the moment a being dies to when it is fossilized and
found. Only a small proportion of the organisms (biocoenosis) are preserved.
Of which only a part is now exposed (thantocoenosisis). See diagram.
Kind of fossils:
- Body fossils: in amber (insects and spiders), ammonites, carboniferous plants, complete
skeletons, bones and teeth, feather imprints and soft tissue preservation.
- Trace fossils: crawling traces, footprints, trackways, coprolite (fossilized shit)
Fossil information hidden within
- Histology: e.g. tree rings
- Stable isotopes
- Molecular fossils (paleoproteomics): e.g. proteins say something about DNA, of which only
the last part of history has DNA preserved (1/2 million years and proteins 1 million years).
Use of fossils:
- Taxonomy: ordering and naming fossil groups.
o Eukaryotes: have a nucleus: animals, plants, fungi and protists
o Archeans: have no nucleus and a single cell membrane
o Bacteria: have no nucleus
Classification based on clades ( = a group consisting of an ancestor and all its descendants
(branch on the tree of life))
o Monophyletic group: consisting of all the descendants of a common ancestor
o Paraphyletic group: shared common ancestor, but not all the descendants included
o Polyphyletic group: grouped together, but do not share an immediate common
ancestor (homoplasy)
- Stratigraphy: erosion, transport, deposition.
Steno: principles of superposition, original horizontality, original lateral continuity and cross
cutting.
o Lithostratigraphy: defines lithological units on basis of observable rock characteristics
o Biostratigraphy: uses fossils in correlating lithostratigraphical units.
- Paleoenvironmental reconstruction: paleobiology, evolution, where do they live, what do
they eat etc. “the present is the key to the past”
, Geological time scale
Chronostratigraphic units: division of rock based on time (Upper and Lower)
Geochronologic units: division of time during which each chronostratigraphic units was formed (Early
and Late)
Lecture 2: Time, biodiversity and enviroment
An ideal GSSP would:
- Be accesible to research
- Be extensive enough to ensure future access
- Be easily related to other exposures worldwide
- Contain a radiometrically datable bed at the boundary
- Include well defined markers at the stage boundary that can be applied worldwide
Dating:
1. Biostratigraphy: relative age: FO en LO, index
fossils
2. Magnetostratigraphy: ~ abolute age: flipping
north and south pole
3. Radioistopes: abosolute age: natural radioactivity
preserved in sediment. If you know the ratio
between two isotopes, you know the age by use
of the half-life
4. Cyclostratigraphy: ~absolute age: eccentricity:
cycles vs ellips, obliquity: angle of earth and
precession: seasonality → insolation curve
