Temporal sequences
1 / 33

Temporal Sequences - PowerPoint PPT Presentation

  • Uploaded on

Temporal Sequences. Maggie Koopman and Erik Hoffmann. 1.5 billion years. 0.0. Now!. Time is on my side. First hard parts. 1.0. First multicellular. 2.0. First eukaryotes. 3.0. First life!. 4.0. The beginning!. The Outcrop. Sometimes you have a lot to work with. The Outcrop.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Temporal Sequences' - cheryl

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Temporal sequences

Temporal Sequences

Maggie Koopman and Erik Hoffmann

Time is on my side

1.5 billion years



Time is on my side

First hard parts


First multicellular


First eukaryotes


First life!


The beginning!

The outcrop
The Outcrop

Sometimes you have a lot to work with...

The outcrop1
The Outcrop

...and sometimes you don’t!

The outcrop2

No crystalline rocks

2 meters = 10 yrs or 10 million?

The Outcrop

  • No absolute dating

  • Imprecise age calibration

Dooley et al., 2004

The outcrop3
The Outcrop


  • Stratigraphic gaps caused by non-deposition or erosion

  • The bigger the time window, the bigger and more frequent the gaps will be

Dooley et al., 2004

The outcrop4
The Outcrop


  • Prevents examination

    • vegetation

    • loose sediment/soil

    • snow/ice/permafrost

Dooley et al., 2004

Temporal sequences

2.5 Ma

100 km

Constant Motion

Modified from Tibert et al., 2003.

Temporal sequences

Schindel, 1982


  • Preservable hard parts only!

  • Morphological change only!

Limitations cont
Limitations cont.

  • Can’t detect fine changes.

  • Small directional changes followed by reversals show up as variability within the population

Geary et al., 2002

Temporal sequences

Punctuated Equilibrium

  • Long periods (relative to species durations) of morphological stasis coupled with brief periods of very rapid morphological change

  • Stasis does NOT mean nothing is happening

    • Changes in soft parts

    • Changes in tolerances/behaviors

    • Small directional morphological change followed by doubling back

Temporal sequences


  • Lineage (size, hard parts, frequency)

  • Location (range, availability)

  • Temporal resolution ((sub)stage level)

  • Character sets

  • Usefulness/Interest

Does the fossil record need to be complete
Does the fossil record need to be complete?

Can we work around the gaps?

Can we derive viable sequences from a spotty record?

Quality of the fossil record through time m j benton m a wills and r hitchin
Quality of the fossil record through timeM. J. Benton, M. A. Wills and R. Hitchin

What does this paper do
What does this paper do?

  • Offers evidence that the fossil record provides uniformly good documentation of past life.

  • Assesses the congruence between stratigraphy

    and phylogeny.

The congruence metrics
The Congruence Metrics

  • Valid techniques for comparing large samples of cladograms to try to estimate variations in congruence between the fossil record for different groups of organisms and for different habitats

  • RCI (relative completeness index)

  • GER (gap ratio index)

  • SCI (stratigraphic consistency index)

Depend on branching point estimates and calc. Of ghost ranges

Stratigraphic consistency index huelsenbeck 1994
Stratigraphic consistency index(Huelsenbeck 1994)

  • Fit of the record to the tree= proportion of the nodes that are stratigraphically consistent.

  • Significance of the fit= generate a null distribution for SCI under the hyp. That the statigraphic fit is not better than expected at random.

Temporal sequences



Fig 1 a/b Benton et al 1999

What causes poor matching of age and clade data bias in the metric
What causes poor matching of age and clade data? left) Bias in the metric

  • Difference in quality of trees

  • Difference in quality of fossil record

  • Stratigraphic problems

  • Taxonomy

  • Sampling density

Molecular clock divergence estimates and the fossil record of cetartiodactyla
Molecular Clock Divergence Estimates and the Fossil Record of Cetartiodactyla

Jessica M. Theodor

J. Paleontology 78 (1), 2004, p 39-44

Why this paper
Why this paper? of Cetartiodactyla

  • Ties molecular clocks to the fossil record

  • Introduces cetaceans and hippopotamids

Molecular clocks vs the fossil record
Molecular Clocks vs. the Fossil Record of Cetartiodactyla

  • Artiodactyla/Cetacea split – 60 Ma

    • Earliest fossil whales 53.5 Ma

    • Earliest fossil artiodactyls 55 Ma

  • Odontocete/Mysticete split – 34-35 Ma

    • Rare at 34 Ma, good record ~30 Ma

  • Hippopotamid/Cetacean split

    • Earliest fossil whales 53.5 Ma

    • Earliest fossil hippos 15.6-15.8 Ma

      • Anthracotheres - ~43 Ma

  • New study using one mitochondrial and one nuclear gene sequence

  • Temporal sequences

    Boisserie et al., 2005 of Cetartiodactyla

    Take home messages
    Take home messages of Cetartiodactyla

    • The fossil record is necessary to calibrate molecular clocks (and refute the bad ones)

    • The fossil record fills gaps in phylogenetic trees, allowing us to confirm evolutionary sequences

    References of Cetartiodactyla

    Benton, M.J., M.A. Wills, and R. Hitchin 2000, Nature. 403, 534-537

    Benton, M.J. 2001, Proceedings of the Royal Society of London B. 268, 2123-2130

    Boisserie, J.-R., F. Lihoreau, and M. Brunet 2005, Proceedings of the National Academy of Science 102 (5), 1537-1541

    Dooley Jr., A.C., N.C. Fraser, and Z.-X. Luo 2004, Journal of Vertebrate Paleontology. 24 (2), 453-463

    Geary, D.H., A.W. Staley, P. Muller, and I. Magyar 2002, Paleobiology. 28 (2), 208-221

    Gingerich, P.D. 1983, Science. 222, 159-161

    Gingerich, P.D. 1984, Science. 226, 995-996

    Gingerich, P.D. 2002, Cetacean Evolution

    Gould, S.J. 1984, Science. 226, 994-995

    Huelsenbeck, J.P. 1994, Paleobiology. 20 (4), 470-483

    Koch, C.F. 1978, Paleobiology. 4 (3), 367-372

    Levinton, J., L. Dubb, and G.A. Wray 2004, Journal of Paleontology. 78 (1), 31-38

    Lihoreau, F., and J.-R. Boisserie 2004, Journal of Vertebrate Paleontology 24 (Supp. 3), 83A

    Rose, K. 2001, Science. 293, 2216-2217

    Schindel, D. 1982, Paleobiology. 8 (4), 340-353

    Schopf, T.J.M. 1982, Evolution. 36 (6), 1144-1157

    Theodor, J.M. 2004, Journal of Paleontology. 78 (1), 39-44

    Tibert, N.E., R.M. Leckie, J.G. Eaton, J.I. Kirkland, J.-P Colin, E.L. Leithold, and M.E. McCormick 2003, in Olson, H.C. and R.M. Leckie, eds., Micropaleontologic Proxies for Sea-Level Change and Stratigraphic Discontinuities: SEPM Special Publication No. 75, 263-299

    Wills, M.A. 1999, Systematic Biology. 48 (3), 559-58