C H A P T E R PREFACE Part I: PHYLOGENY AND GEOGRAPHIC RADIATION Tree of Ursid Ancestry 1. THE EARLIEST BEARS * Miacids - the Eocene Progenitor * Miocene Ancestors Ursavus, Protursus, 2. AGRIOTHERINAE * Indarctos, and Agriotherium * Ancestors of the Tremarctinae and Ursinae 3. TREMARCTINAE * Spectacled Bears Tremarctos o North America: Florida cave bear o South America: Andean spectacled bear * Short-Faced Bears Arctodus o North America a. Lesser short-faced bear b. Giant short-faced bear o South America: 3 species 4. URSINAE * Ursus minimus and U. abstrusus * Asian and American black bears * Etruscan and cave bears * Brown/grizzly bear * Polar bear * Sun and sloth bears 5. AILUROPODINAE * Panda Bears * Panda Coons - procyonids 6. TAXONOMIC CHALLENGES: genetic vs. epigenetic determination of skull morphology Part II: THE EVOLUTIONARY ENVIRONMENT 7. GEOGRAPHY, CLIMATE, AND BIOTA * Continental drift * Climatic change o Temperature and moisture o Seasonality: Pleistocene vs. Holocene * Sea level fluctuation * Travel barriers and routes o Water o Deserts and grasslands o Ice and mountains * Biota o Mammoth steppe and other grasslands o Vegetative diversity and distribution o Habitat carrying capacity o Animals of possible significance to bears * Megafaunal extinctions o Types of species that became extinct o Causes of extinction 8. HABITATS COLONIZED * Arboreal and terrestrial * Tropical and subtropical * Temperate and arctic * Caves Part III: ADAPTATIONS & ECOLOGICAL RADIATION 9. PELAGE 10. SENSES 11. HANDS, FEET & CLAWS 12. FOOD HABITS * Herbivory * Myrmecophagy * Omnivory * Carnivory 13. SKULL & DENTITION 14. BODY SIZE * Evolutionary trends and fluctuations * Local variation among European cave bears * Differences among extant species 15. DEFENSE AGAINST ENEMIES Part IV. INTER-URSID RELATIONS AND EXTINCTION 16. INTER-URSID RELATIONS AND EXTINCTION * Coexistence * Competition and extinction SUMMARY & CONCLUSIONS Preface.htmlTree%20of%20Ancestors.html1%20Primordial%20Bears.html2%20Agriotherinae.html3%20Tremarctinae.html4%20Ursinae.html4%20Ursinae.html4%20Ursinae.html4b%20Cave%20bears.html4c%20Grizzly%20%26%20brown%20bears.html4c%20Grizzly%20%26%20brown%20bears.html4c%20Grizzly%20%26%20brown%20bears.html5%20Ailuropodinae%20-%20Pandas.html6%20Taxonomic%20Challenges.html7%20Geography,%20Climate%20%26%20Biota.html8%20Habitats%20Colonized.html8%20Habitats%20Colonized.html8%20Habitats%20Colonized.html11%20Hands,%20Feet%20%26%20Claws.html12%20Food%20Habits.html13%20Skull%20%26%20Dentition.html14%20Body%20Size.html15%20Defense%20Against%20Enemies.html16%20Inter-Ursid%20Relations%20%26%20Extinction.htmlSummary%20%26%20Conclusions.htmlshapeimage_3_link_0shapeimage_3_link_1shapeimage_3_link_2shapeimage_3_link_3shapeimage_3_link_4shapeimage_3_link_5shapeimage_3_link_6shapeimage_3_link_7shapeimage_3_link_8shapeimage_3_link_9shapeimage_3_link_10shapeimage_3_link_11shapeimage_3_link_12shapeimage_3_link_13shapeimage_3_link_14shapeimage_3_link_15shapeimage_3_link_16shapeimage_3_link_17shapeimage_3_link_18shapeimage_3_link_19shapeimage_3_link_20shapeimage_3_link_21shapeimage_3_link_22shapeimage_3_link_23shapeimage_3_link_24
Note:  This book was written in 1992 for publication in hardcopy.  Unfortunately, job demands forced me to shelve the project.  During the intervening 16 years, there has never been time to update it.  So I am publishing it online as the most thorough review available of literature up to 1992, encompassing almost 200 sources.  Hopefully, this synthesis will still save any student of bear evolution a great deal of time getting to know the older literature.  
 
I am also adding a bit of new material here and there within existing chapters, as well as putting in new chapters.  The sections being modified are clearly marked in blue or red (e.g., “under construction”) so there should be no confusion about what can be safely cited.  
 
You likely know how Wikipedia advances through input by any interested reader.  I would like to do something similar here.  If you have ideas on revising this manuscript, for instance by adding newer information or topics I have not yet addressed, feel free to email your submissions to me at bearcommunication@hotmail.com.  Brief suggestions may be incorporated into the existing text.  Longer essays will likely be added to the website as a separate webpage, accessed through a hotlink.  In either case, you will be credited in a footnote.
 
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