Post on 11-Jan-2016
Todd A. Radenbaugh, PhDResearch FellowCanadian Plains Research Center
Paleontology in Decline:Making Fossils Live Again
Geological Society of America16-19th,October, 2005
Salt Lake City, UT
Evolution Under Siege
On May 5, 1925, biology teacher John Scopes was arrested for teaching Darwin's theory of evolution in violation of
Tennessee state law.
August 11, 2005
NEW Monkey Trials
http://www.theonion.com
Pennsylvania school board's
decision to teach both intelligent
design and evolution
Apr 2004
New Mexico Schools C
ould Enter
Battle Over 'In
telligent D
esign'
(The Washington Post)
By Martha Raffa
ele, Page A07,
October 09, 2005
Geologist wanted:Posted January, 2005 from:
COLLEGE OF ARTS AND SCIENCES- Dr. R Hawkins, Dean.
Geology: Ph.D. required. Teaching Introductory Geology, Paleontology, and History of Life.
Contact:Liberty University1971 University Boulevard, Lynchburg, Virginia 24502
434-582-2000
New Vision of the Future?
Compatibility with a young-earth creationist position required…
http://www.liberty.edu/Administration/HumanResources/index.cfm?PID=4353
Making Paleontology Relevant
Paleontology courses need to be made more relevant in geology and environmental science departments’ curricula.
• The economy is dependent on fossil fuels.• Anthropogenic forced climate change, habitat loss, and alteration of natural selection pressures has caused extinctions and extensive changes.
No longer concentrate on only morphology and taxonomy.
Paleontology in Virginia
Virginia Universities – Bachelor Programs
Public (n=15)Geology Programs = 5 (33%)Geology Classes = 12 (80%)
Paleo Classes = 7 (47%) College of William and Mary (2)
George Mason UniversityJames Madison University
Old Dominion University (2)Radford University (2)
University of Mary WashingtonVirginia Tech (2)
Private (n=22)Geology Programs = 1 (5%)Geology Classes = 12 (55%)
Paleo Classes = 2 (9%)Virginia Wesleyan College
Washington and Lee
Most Geology classes are Taught in Environmental Studies Departments
37 Virginia Universities – Bachelor Programs
Department Type #
Geology
Paleo classes
6
6
Environmental and Earth Sci.
Paleo classes
16
3 (19%)
Other (Physical sciences, Science survey, etc.)
Paleo classes
3
0
None
Paleo classes
12
0
0
2
4
6
8
10
12
14
16
Geol Paleo
Geology
Env. /EarthSci
Other
No Geol
Retooling Paleontology
• Link recent environmental change to its geologic history• Use evidence from paleoecology and glean lessons for society and economy.
Make room for Paleo and macroevolution classes in the environmental science curricula
Two examples
1. Ediacaran Fauna Reconstruction
• To show different ecological rules of assembly
2. Comparisons between Modern and Paleozoic Ecospace Use
• Extinctions - past and present
Two examples of how to use paleontological theory relevant to today’s environmental science programs:
Ediacaran Fauna Example
650 to 540 Million years ago frond-like forms, jellyfish-like imprints, and trace fossils. Perhaps evolved as nutrient supplies increased in
shallow waters causing a radiation of trophic links in food webs
Photo Credit: http://www.ucmp.berkeley.edu/vendian/critters.html
Garden of Ediacara
A time when today’s rules of ecological assembly did not apply.• No major predators
• Few mobile fauna
• Dominated by suspension feeding
Ediacaran Fauna Clay reconstructions
Ediacaran Fauna
Complete reconstructions of students
Ecospace Example
From Bambach (1983)
Megaguild: Summation of the guilds occupied by a species or group of species.
Ecospace: ecological resources used by species based on adaptive morphologies (bauplan), space utilization, and food sources
Shallow Marine Megaguilds Through Time
Tiering and Bulldozing
-100
-50
0
50
100
C O S D M P P Tr J K T Q
Sed
imen
t-w
ate
r in
terf
ace (
cm
)
Max Above Max below
v
From Ausich and Bottjer 1982
Trace Fossil
Paleozoic Bulldozing – Changes in Ecological Rules of Assembly
Crab burrows
Gastropods Pelcypods
Irregular echinoids
Bulldozers Victims
Blastoid reconstruction
Bryozoans
Brachiopods
Sponges
Crinoids Columinals
EpS
SE
nS
DE
nS
SE
NS
D
DE
nSD
P/H
Oth
er
0
0.5
1
1.5
2
2.5
Imp
ort
ance
Val
ue
Magaguild
Recent
Mississippian
Ecospace Comparisons of a Modern and Late Paleozoic Assemblage
Megaguild KeyEpS = Epibenthic suspensionSEnS = Shallow endobenthic suspensionDEnS = Deep endobenthic suspensionSENSD = shallow endobenthic surface depositDEnSD = Deep endobenthic surface depositP/H = Predator or Herbivore
Ecosystem Stability
Assemblage restructuring.1. Changing resource use -> new organisms create or occupy new niches and guilds.2. Guild decline and species extinction -> Decline or loss of old niches and guilds.3. Speciation -> Vacant niches are filled by newly evolved species, some are similar to previous ones but new guilds cause different assemblage types (change in rules how species associations are structured).
Stable ecosystems: Persistence of similar niches and guilds within species
assemblages, and the same lineages occupy these niches and guilds for extended periods of geological time (3-7 m.y.).
Little selection pressure and speciation.
Are We Changing the Landscape?
What broad scale changes to biotic structure have occurred as a result of human activities similar to those in the fossil record?
Can human activities act as a selection force with the capacity to change the functional roles and assembly rules at the ecosystem level?
Estimation of Vegetation Changes Mixed Grassland Ecoregion of Saskatchewan
0 20 40 60 80 100
1990s
Circa 1880
Grassland
Woodland
Wetland
Cultivated
Sources:
Pre-1880 - Archibold and Wilson (1980)
1990s - Statistics Canada, 1986, 1991 and 1996 Agricultural Census and the South Digital Land Cover
Adapted form Bambach (1985)
Ecospace for Birds
Foraging MethodDabbler
Diver
Gleaner
Picker
Prober
Sallier
Stalker
Swooper
Foraging HabitatBrush/woodland
Grassland
Wetland
Other
Nesting HabitatCavity
Cliff
Ground
Floating Mat
Vegetation
DietSeeds
Omnivore
Aquatic-invertebrates
-vertebrates
-vegetation
Terrestrial-invertebrates
-vertebrates
-vegetation
Bird Assemblages Comparisons1990s
Present Absent
Present 108 2Circa 1900 Absent 25 0
Match Coefficient = 0.80
Total Species = 135
* Calculated using the Shannon-Weiner index : the relative abundance score was substituted for number of individuals.
Circa 1900 1990’s
Species Richness 110 133
Species Diversity* 1.89 2.11
Horn’s Index of Similarity* = 0.77
Guild and Habitat Trends
Guild Type Guild Habitat Trend Guild trendForaging Habitat Brushland/woodland + +0.69
Grassland - -0.29Wetland - -0.19Other + +0.35
Nesting Habitat Cavity + +0.81Cliff + +0.60Ground - -0.21Floating Mat - -0.24Vegetation + +0.44
**
*
**
***
Significance: ** p<0.01; *p<0.05 by Mann-Whitney test
Extinction rate 100 to 1,000 times more rapid than before human domination – one species every hour to minute• “…two-thirds of all species of plants, animals and organisms could be lost in the second half of the next century.” Peter Raven, 2003
Similar scale those in the fossil record.At this rate we may loose 20% of families or 55% of species in the next 100 years.
From Raup and Sepkoski 1992
Extinctions
Extinction Recovery
How long does it take to recover from a mass extinction event?
The origination rate peaks about 20 million years after the peak in extinction rates
From Sepkoski's 1998
Conclusions
Using paleoecology analogs, we can show that current trends are changing the landscape in terms of:
resource use regional species composition
Evolution’s influences on the biosphere, atmosphere, oceans, and solid earth making it a key topic in environmental science departments.
Paleontology tell us how ecosystem structure has changed, and how it might change.
Regional natural selection forces are diversifying and evolutionary changes as seen in the fossil record may be occurring.
Future?
If current declining trends towards paleontology continue,
there will be negative long-term consequences to science and society
in understanding our future.