Changing Life Over Time Activities

Changing Life Over Time Activities

© 2002 American Geological Institute. http://www.agiweb.org

Contents: All Activities and Investigations
Activity 1 
Activity 2 
Activity 3 
Activity 4 
Activity 5 

Preparing a display to educate the community about biological changes in the area. Students learn about the evidence for changing life and the factors that can cause biological changes over time. 
Students will:

• Understand how biological changes are tied to all of the Earth systems. 
• Participate in scientific inquiry and construct logical conclusions based on evidence. 
• Appreciate the value of Earth science information in improving the quality of life, globally and within the community. 

Activity 1  --  The Fossil Record and Your Community

To learn more about this topic, visit the following web sites:
 

1.  Food Chains and Food Webs

• Energy Flow and Food Web, Louisiana State University 

This page includes an overview of an entire powerpoint presentation plus annotated notes along side about food webs.  In addition, part of the notes focus on a case study involving sea otters in the Northern Pacific. 
http://zooplankton.lsu.edu/web_2008/energy_flow_web/energy_flow.htm
• Food Chains and Webs, Marietta College 

This college web site provides information on the the food chain and the complexity of food webs. Information on the relationship to biomass and trophic levels is also explored.
http://www.marietta.edu/~biol/102/ecosystem.html#FoodChainsandWebs4

2.  What is a Fossil?

• Fossils and Rocks, Fossils, Rocks and Time, USGS 

A section in this online publication, this page provides a little background to how studying fossils became an important part of understanding geologic time. 
http://pubs.usgs.gov/gip/fossils/fossils-rocks.html
• Fossil Encyclopedia, Royal Tyrrell Museum 

This is a useful resource, especially if you are interested in a very specific species as well as brief descriptions of groups of species.
http://www.tyrrellmuseum.com/encyclo/b.html

3.  Fossilization

• Fossilization and Preservation, Paleontology Laboratory Manual - University of Arizona 

This page is part background reading and part directions for a lab examining how a particular fossil has been preserved.
http://www.geo.arizona.edu/geo3xx/308/cha1.html

4.  Fossiliferous Rocks

• Mazon Creek Fossils, Illinois State Museum 

The plants and animals found in concretions recovered from the Francis Creek Shale are some of the most exciting and important fossils that have been found in the state of Illinois. These fossils are known as the Mazon Creek fossils, because they were originally found along Mazon Creek in northeastern Illinois. This exhibit shows some of the more interesting and dramatic types of fossils recovered from these remarkable deposits. 
http://www.museum.state.il.us/exhibits/mazon_creek/index.html

To complete the Inquiring Further section of this activity: To learn more about taphonomy and forensic science, visit the following web sites:

• A Brief Introduction to Taphonomy, Colby College 

This articles details what, how, and why different organisms are fossilized.
http://www.colby.edu/~ragastal/Taphonomy.htm
• Taphonomy and Preservation, SUNY Cortland 

The text includes a similar to other discussions, the page also features a table that summarizes different taphonomic indicators and their paleoenvironmental implications.  At the bottom of the page, there is a link to a separate article about preservation.
http://paleo.cortland.edu/tutorial/Taphonomy%26Pres/taphonomy.htm 
• Career Brochure, American Academy of Forensic Sciences 

Learn about different careers in the forensic sciences.
http://www.aafs.org/employ/brochure1.htm
• Young Forensic Scientists Forum (YFSF) 

The Young Forensic Scientists Forum (YFSF) is a group within the American Academy of Forensic Sciences (AAFS) that is dedicated to the education, enrichment and development of emerging forensic scientists and future leaders of the field.
http://www.aafs.org/yfsf/index.htm
To learn more about common geological settings for preservation, visit the following web sites:
• Preservation and Bias in the Fossil Record, University of California at Davis 

Considering that "Hardly any substances were selected for their properties after death," it is remarkable what we know about organisms that lived millions of years ago.  Find out more about why the depositional setting that is the organism's final resting place is important if the organism is to become part of the fossil record.
http://www-geology.ucdavis.edu:8000/~gel3/biases.html

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Activity 2  --Biomes

To learn more about this topic:
 
Climate and Biomes
• Biomes, Exploring the Environment 

Scientists have divided the broad spectrum of climates and ecological communities found on Earth into biomes in different ways - some with many divisions, some with only a few.  This site focuses on some of the common biomes with photos that accompany separate descriptions of each.
http://www.cotf.edu/ete/modules/msese/earthsysflr/biomes.html
• Arctic Tundra 
• Deciduous Forest 
• Desert  
• Taiga 
• Tropical Rainforest 
• Tropical Savannah 
• Mission Biomes, Earth Observatory, NASA 

http://earthobservatory.nasa.gov/Laboratory/Biome/
Topics covered on this page include:
• Tundra 

http://earthobservatory.nasa.gov/Laboratory/Biome/biotundra.html
• Shrubland 

http://earthobservatory.nasa.gov/Laboratory/Biome/bioshrubland.html
• Rainforest 

http://earthobservatory.nasa.gov/Laboratory/Biome/biorainforest.html
• Grassland 

http://earthobservatory.nasa.gov/Laboratory/Biome/biograssland.html
• Desert 

http://earthobservatory.nasa.gov/Laboratory/Biome/biodesert.html
• Temperature Deciduous Forest 

http://earthobservatory.nasa.gov/Laboratory/Biome/biotemperate.html
• Coniferous Forest 

http://earthobservatory.nasa.gov/Laboratory/Biome/bioconiferous.html
• Biomes for Teachers! University of Richmond 

This page includes links to other sources of background information, a slide show of biomes, activities, and lesson plans.
http://www.richmond.edu/~ed344/webunits/biomes/teacher.html
To complete the investigation, each student group will need:
• Internet access - 

To find scientific information about most common plants and animals in your biome, visit the following web sites:
• Exploring the Environment 
• Arctic Tundra Animals 

http://www.cotf.edu/ete/modules/msese/earthsysflr/tundraA.html
• Arctic Tundra Plants 

http://www.cotf.edu/ete/modules/msese/earthsysflr/tundraP.html
• Deciduous Forest Animals 

http://www.cotf.edu/ete/modules/msese/earthsysflr/dforestA.html
• Deciduous Forest Plants 

http://www.cotf.edu/ete/modules/msese/earthsysflr/dforestP.html
• Desert Animals 

http://www.cotf.edu/ete/modules/msese/earthsysflr/desertA.html
• Desert Plants 

http://www.cotf.edu/ete/modules/msese/earthsysflr/desertP.html
• Taiga Animals 

http://www.cotf.edu/ete/modules/msese/earthsysflr/taigaA.html
• Taiga Plants 

http://www.cotf.edu/ete/modules/msese/earthsysflr/taigaP.html
• Tropical Rainforest Animals 

http://www.cotf.edu/ete/modules/msese/earthsysflr/rforestA.html
• Tropical Rainforest Plants 

http://www.cotf.edu/ete/modules/msese/earthsysflr/rforestP.html
• Tropical Savannah Animals 

http://www.cotf.edu/ete/modules/msese/earthsysflr/savannahA.html
• Tropical Savannah Plants 

http://www.cotf.edu/ete/modules/msese/earthsysflr/savannahP.html
• Introduction to Biomes, Radford University 

Each of the pages below outlines the animals and plants that live in that particular biome. 
http://www.runet.edu/~swoodwar/CLASSES/GEOG235/biomes/intro.html
• Tundra 

http://www.runet.edu/~swoodwar/CLASSES/GEOG235/biomes/tundra/tundra.html
• Boreal Forest or Taiga 

http://www.runet.edu/~swoodwar/CLASSES/GEOG235/biomes/taiga/taiga.html
• Deciduous Forest 

http://www.runet.edu/~swoodwar/CLASSES/GEOG235/biomes/savanna/savanna.html
• Tropical Evergreen Forest 

http://www.runet.edu/~swoodwar/CLASSES/GEOG235/biomes/rainforest/rainfrst.html
• Tropical Savannah 

http://www.runet.edu/~swoodwar/CLASSES/GEOG235/biomes/savanna/savanna.html
• Desert Scrub 

http://www.runet.edu/~swoodwar/CLASSES/GEOG235/biomes/desert/desert.html
• Temperate Grasslands 

http://www.runet.edu/~swoodwar/CLASSES/GEOG235/biomes/tempgrass/tempgras.html
• Mediterranean Scrub 

http://www.runet.edu/~swoodwar/CLASSES/GEOG235/biomes/medit/medit.html
• Characteristics of the Earth's Terrestrial Biomes, Okanagan University College 

Here is another article that provides descriptions of the animals and plants in different biomes.
http://www.geog.ouc.bc.ca/physgeog/contents/9k.html
To complete the Inquiring Further section of this activity:
To learn more about herbivores and carnivores, visit the following web site:
• The Energy Pyramids, World Builders 

Check out this site with an energy pyramid for several different biomes.  Click on a "K Calorie Pyramid" link under each biome (for example, Hot Desert at http://www.world-builders.org/lessons/less/biomes/desert/hot-despy.html) to see the number of calories the carnivores must obtain from the herbivores to survive.
http://www.world-builders.org/lessons/less/biomes/introbiomes.html
To learn more about Alaskan animal adaptations to climate, visit the following web site:
• Alaska Wildlife Notebook Series, Alaska Department of Fish and Game 

Read about Alaskan big game, marine mammals, small game, birds, furbearers, fish, shellfish, amphibians, or reptiles.
http://www.state.ak.us/adfg/notebook/notehome.htm

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Activity 3  --  Your Community and the Last Glaciers

To learn more about this topic:

1.  Pollen and Spores
• Fossil Groups: Spores and Pollen, USGS 

By analyzing pollen from well-dated sediment cores collected at critical sites, it is possible to obtain high-resolution records of vegetation change with decadal-scale resolution and to document community changes over the last few centuries and millennia.
http://geology.er.usgs.gov/paleo/sporepollen.shtml
• List of Palynology Educators, University of Arizona 

Find a scientist who studies pollen near you!  Check out links to individual web sites organized by region.
http://www.geo.arizona.edu/palynology/web_acad.html
2.  Paleoclimate
• Weather, Climate, and Paleoclimate, NOAA Paleoclimatology Program 

What is paleoclimatology?  How do we measure paleoclimate? What can paleoclimatology tell us about climate change relevant to society in the future?  Find out the answers to these interesting questions. 
http://www.ngdc.noaa.gov/paleo/globalwarming/paleo.html
• Paleoclimate, Goddard Institute for Space Studies, NASA 

Learn about current research at the Goddard Institute for Space Studies that centers upon the use of global climate models (GCMs) to generate simulations of past climates. 
http://www.giss.nasa.gov/research/paleo/
3.  The Response of Biomes to Climate Change
• EPA Global Warming: State Impacts, Environmental Protection Agency 

Find out how climate change will affect your state forests and ecosystems.
http://www.epa.gov/globalwarming/impacts/stateimp/index.html
• Or learn about impacts in different regions: 
• Polar Regions 

http://www.epa.gov/globalwarming/impacts/polarregions/index.html
• Mountains 

http://www.epa.gov/globalwarming/impacts/mountains/index.html
• Forests 

http://www.epa.gov/globalwarming/impacts/forests/index.html
• Rangelands 

http://www.epa.gov/globalwarming/impacts/rangelands/index.html
• Deserts 

http://www.epa.gov/globalwarming/impacts/deserts/index.html
• Non-tidal Wetlands 

http://www.epa.gov/globalwarming/impacts/wetlands/index.html
• Coastal Zones 

http://www.epa.gov/globalwarming/impacts/coastal/index.html
Part B: Your Community Biome: Pleistocene to Present
To complete the investigation, each student group will need:
• Internet access: to view information about pollen distribution from the Late Pleistocene to the present, visit the following web sites: 
• Animated Maps of Vegetation Change, University of Oregon 

The Quaternary Environments group at Brown in collaboration with Professor Patrick Bartlein of the Department of Geography at the University of Oregon have mapped the changing spatial distributions of pollen percentage for over 50 taxa from 21,000 calendar years ago to present. Maps of biomes derived from the pollen data and maps of multiple taxa were also include to show how the vegetation changed.  *Unfortunately, there is a gap in the data available on this site that covers most of the western United States.
http://www.geo.brown.edu/georesearch/esh/QE/QEHome.html 
• North America During the Last 150,000 Years, Oak Ridge National LaboratoryVegetation in North America has been continually changing over the last 150,000 years.  This page provides brief descriptions and maps that detail these changes in smaller units of time.  

*The graphics are a little fuzzy, but the text descriptions are very useful.
http://www.esd.ornl.gov/projects/qen/nercNORTHAMERICA.html
• Internet access: to view information about distribution of animals from the Late Pleistocene to the present, visit the following web sites: 
• FAUNMAP: An electronic database documenting late Quaternary distributions of mammal species, Illinois State Museum

http://www.museum.state.il.us/research/faunmap/aboutfaunmap.html *The Faunmap site is currently under construction and the interactive capabilities are not working (as of 7/30/02). In the meantime, you can use a subset of the data to look at fauna found in the Los Angeles area from 40,000 years-present. http://mapserver.museum.state.il.us/faunmapweb/LosAngeles.html
To complete the Inquiring Further section of this activity:

To learn more about carbon-14 dating techniques, visit the following web sites:
• Radiocarbon Dating, Radiocarbon WebInfo 

The information on this page answers the following questions: How was radiocarbon dating developed?  How does radiocarbon dating work?  What kind of things can you date using radiocarbon?  How did Libby test his method and find out if it worked correctly?  How much sample material do you need to date using radiocarbon?  How much does it cost to date using radiocarbon dating?  What are the oldest things that can be radiocarbon dated?  What is the youngest thing that can be radiocarbon dated? And more.
http://www.c14dating.com/k12.html
• Radiometric Dating, Georgia Perimeter College 

This discussion includes the principles of radiometric dating as well as explaining how Carbon-14 dating works.
http://www.dc.peachnet.edu/~pgore/geology/geo102/radio.htm
To learn more about late Pleistocene extinctions, visit the following web sites:
• Late Pleistocene Extinctions, Illinois State Museum 

This brief overview addresses whether human hunting or environmental changes were to blame for the Late Pleistocene extinctions.  Plus it answers whether or not North American animals went extinct at this particular time in geologic history.
http://www.museum.state.il.us/exhibits/larson/LP_extinction.html
• The Three Main Hypotheses, American Museum of Natural History 

For two days in April 1997 three hundred scientists, journalists, policy makers and people  like yourself gathered at the American Museum of Natural History to participate in the spring symposium titled "Humans and Other Catastrophes."
Three main hypotheses surfaced as to the source of the extinctions at the end of the Pleistocene: Overkill, Disease, and Climate.  Read about each theory and see which one you agree with.
http://www.amnh.org/science/biodiversity/extinction/Day1HypothesesFS.html

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Activity 4  --  The Mesozoic-Cenozoic Boundary Event

To learn more about this topic:
 
1.  The Extinction Event at the End of the Mesozoic
• A Blast from the Past, National Museum of Natural History 

http://www.nmnh.si.edu/paleo/blast/index.html
This site offers several pages about the mass extinction at the end the Cretaceous period (at the end of the Mesozoic Era) and the beginning of the Tertiary Period (early Cenozoic Era) including the following:
• K/T Boundary 
• The Asteriod Hypothesis 
• The Core 
• References and Related Links 
• Interview with Dr. Brian Huber - Dr. Huber is a micropaleontologist from the National Museum of Natural History and member of the Ocean Drilling Program expedition team that recovered the deep-sea core featured in the exhibit. 
• See more links below for Part A of this investigation. 
2.  The Causes of Extinction
• Chicxulub and the Cretaceous Tertiary Boundary, NASA/UA Space Imagery Center's Impact Cratering Series 

This site is under construction but it already has detailed information.  In addition to a description of the asteroid hypothesis, the homage links browses to information about local and global effects of the impact, plus a glossary under the Students and Teachers button.
http://www.lpl.arizona.edu/SIC/impact_cratering/Chicxulub/Chicx_title.html
• Cretaceous Tertiary Boundary - Reading List, Lamont Doherty Earth Observatory, Columbia 

Interested in finding more resources about the K/T Boundary, check out this reading list.  It is worth noting that most of the list is of particular scientific papers.
http://www.ldeo.columbia.edu/eesj/casestudies/EESJktbound.html

Part A: Changes in Climate and Life at the End of the Mesozoic Era
To complete the investigation, each student group will need:

• Internet access: to view information about paleoclimate before and after the Cretaceous-Paleogene boundary, visit the following web sites:  
• Cretaceous: Tectonics and Paleoclimate, Museum of Paleontology 

A description of the paleoclimate in the Late Cretaceous
http://www.ucmp.berkeley.edu/mesozoic/cretaceous/crettect.html
• Late Cretaceous Climate versus Paleocene Climate, Paleomap Project 

Compare climate maps of the Late Cretaceous to the early Paleogene (Paleocene).
The entire list of climate maps is available at http://www.scotese.com/climate.htm
• The Paleocene, National Museum of Natural History 

The paleoclimate plus flora and fauna that dominated the early Paleogene
http://www.mnh.si.edu/anthro/humanorigins/faq/gt/cenozoic/paleocene.htm
• Internet access: to view information about organisms living before and after the Cretaceous-Paleogene boundary, visit the following web sites: 
• Cretaceous Period: Life, Museum of Paleontology 

The flora and fauna of the Late Cretaceous 
http://www.ucmp.berkeley.edu/mesozoic/cretaceous/cretlife.html
• The End-Cretaceous (K-T) Extinction, Hooper Virtual Paleontology Museum 

Species effected by the catastrophic event that resulted in the mass extinction at the K-T boundary
http://hannover.park.org/Canada/Museum/extinction/cretmass.html
• Paleocene Mammals of the World, Museum of Paleontology 

The first 10 million years of the age of mammals
http://www.paleocene-mammals.de/

To complete the Inquiring Further section of this activity:

To learn more about hypotheses to explain the Mesozoic-Cenozoic boundary event, visit the following web sites:
• Cretaceous-Tertiary Boundary: Evidence for Catastrophe, Rochester University 

Two very prominent theories are the collide impact theory and the volcanic theory; the former is discussed here.
http://www.earth.rochester.edu/ees201/Larson/larsona1.html
To learn more about other mass-extinction events in Earth's history, visit the following web sites:
• Mass Extinctions, Hooper Virtual Paleontological Museum 
Read a short discussion about mass extinctions in general.  At the bottom of the page, select between two different menus to find descriptions of mass extinctions through the Phanerozoic and PreCambrian Eons.
Main Page: http://hannover.park.org/Canada/Museum/extinction/massextinc.html
Mass Extinctions of the Phanerozoic: http://hannover.park.org/Canada/Museum/extinction/extincmenu.html
Mass Extinctions of the Precambrian and Vendian: http://hannover.park.org/Canada/Museum/extinction/venmass.html
• Extinctions, About.com 

Interested in just browsing through different links on mass extinction.  Try the selection under the Extinction section on About.com.
http://geology.about.com/cs/extinction/

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Activity 5  --  How Different Is Your Community Today from that of the Very Deep Past?

To learn more about this topic:
 
1.  Biodiversity and Climate Change
• Biodiversity and Climate Change: Impacts on biodiversity, Biodiversity and Climate Change Programme-United Nations Environment Programme World Conservation Monitoring Centre 

Shifts in distribution of plants and animals, barriers to movement, changing patterns of precipitation and evaporation, and other topics are explored at this site. It also provides a list of sensitive ecosystems ordered by biome, ecosystem, or landscape type, key climatic variables, and implications for biodiversity.
http://www.unep-wcmc.org/climate/impacts.htm
• Biodiversity: buffer against climate change, Environmental News Network 

This article sites a specific research study at the University of Minnesota called BioCON that explores the way plant communities will respond to environmental changes which are believed to be occurring on a global scale.  Go to the project homepage at http://www.lter.umn.edu/biocon/
http://www.enn.com/news/enn-stories/2001/05/05102001/biodiversity_43462.asp

  To complete the Inquiring Further section of this activity:
To learn more about extinctions, visit the following web sites:

• Ask the Experts, Scientific American 

Get three different opinions about mass extinctions when three geologists answered the following questions:  what ever happened to the theory of periodic mass extinctions, which stated that major extinctions occur every 26 million years? Is it widely accepted? And when was the last such extinction--have there really been two of them since the dinosaurs died off 65 million years ago? 
http://www.sciam.com/askexpert/geology/geology2.html
• Also check out the links to sites about mass extinctions in Activity 4. 
To learn more about originations, visit the following web sites:
• Extinctions and Originations, Rice University 

These lecture notes are clear out of context (of the lecture) and address how originations are connected to mass extinctions.
http://www.ruf.rice.edu/~queller/Bios334/lectures/15_Extinctions_and_origins.html

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Resources

: Web Sites:

• Learning from the Fossil Record, Museum of Paleontology, University of California 

http://www.ucmp.berkeley.edu/fosrec/index.html
• Evolution and the Fossil Record, American Geological Institute 

http://www.agiweb.org/news/evolution/
• Paleontological Research Institute 

http://www.priweb.org/
• The Paleontological Society 

http://www.paleosoc.org/
• Natural Museum of Natural History, Smithsonian 

http://www.mnh.si.edu/
• American Museum of Natural History 

http://www.amnh.org/
• The Field Museum 

http://www.fmnh.org/

Maps:

• Geologic maps: State and local: 
• The United States Geological Survey National Geologic Map Database contains information on how and where to obtain geologic maps. (http://ngmdb.usgs.gov/) 
• Your state Geological Survey - find your state survey on-line at Association of American State Geologists (http://www.kgs.ukans.edu/AASG/AASG.html). 
• Download state geologic maps at About.com's site.  (http://geology.about.com/science/geology/cs/geomapsusstates/) 
• Reading Geologic Maps - informative review on how to read and interpret geologic maps.  (http://geology.about.com/science/geology/library/weekly/aa100800a.htm) 

 
• Geologic maps: Regional (two or more states): 
• The on-line bookstore of the American Association of Petroleum Geologists (http://bookstore.AAPG.org; 918-584-2555) 
• Topographic maps: Local 
• The United States Geological Survey MapFinder allows you to order 7.5 minute maps online for $4 per map plus $5 s/h per order. (http://edc.usgs.gov/Webglis/glisbin/finder_main.pl?dataset_name=MAPS_LARGE) 
• The United States Geological Survey maintains a list of Map Dealers.  Click on your state to obtain a list of retailers who sell maps. (http://mapping.usgs.gov/esic/map_dealers/) 
• The United States Geological Survey National Geologic Map Database site on How to find topographic maps (http://ngmsvr.wr.usgs.gov/Other_Resources/rdb_topo.html) 
• TopoZone site allows you to download topographic maps (including USGS maps) for free, at various scales (from 1:100,000 to 1:24,000).  (http://www.topozone.com/) 
• MapServer offers free online viewing of topo, nautical and aeronautical charts plus high altitude digital ortho quads (nav photos). (www.maptech.com and www.mapserver.maptech.com) 
• General Map Resources: 
• An excellent list of map resources available online can be found on the Central Michigan University Resources for Earth Science and Geography Instruction web site.  Included are links to sites to make maps, as well as links to free downloadable outline maps, satellite imagery, GPS, and GIS databases. (http://personal.cmich.edu/~franc1m/locamap.htm) 
• "Maps" - USGS Earth Science Information Center, includes general map information, from how to read maps to how to obtain them.  Also includes links to further information regarding topographic, thematic, planetary maps, and more. (http://ask.usgs.gov/maps.html) 
• National Geographic (maps and videos): 1-800-962-1643 (http://www.nationalgeographic.com/maps/index.html) 
• "Maps of the United States" - USGS fact sheet, contains a series of depictions of the United States, along with information on how to obtain additional US maps. (http://www.usgs.gov/fact-sheets/maps-us/index.html) 
• "Maps of the World" - USGS fact sheet, contains a series of world maps, including outline maps, seismicity maps, and political maps.  Also contains information for ordering more specific world maps. (http://www.usgs.gov/fact-sheets/maps-world/maps-world.html) 
• "National Atlas Maps" - USGS site of a variety of US maps that are available online, including shaded relief maps, aquifer maps, and further information on how to order maps not available online.  (http://www-atlas.usgs.gov/atlasmap.html?) 

Videos: Books:

• Suggested Readings, Evolution and the Fossil Record, AGI and The Paleontological Society. 

http://www.agiweb.org/news/evolution/readings.html

Magazines:

• Geotimes.  Published by the American Geological Institute, this magazine reviews current issues in the Earth Sciences and can serve as a valuable supplemental resource for teachers and students alike.  Visit the web site for online articles and information about obtaining a one-year subscription (40% discount for AGI Member Society members; 65% discount for students). 

(http://www.geotimes.org/current/)
• Excellent sources of high-school level articles are in both National Geographic (which often has maps), and Science News 

(describing the most recent and interesting events in scientific research.) 

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