Scientists strive to develop clear rules for naming and grouping living organisms. But taxonomy, the scientific study of biological classification and evolution, is often highly debated. Members of a species, the fundamental unit of taxonomy and evolution, share a common evolutionary history and a common evolutionary path to the future. Yet, it can be difficult to determine whether the evolutionary history or future of a population is sufficiently distinct to designate it as a unique species. A species is not a fixed entity—the relationship among the members of the same species is only a snapshot of a moment in time. Different populations of the same species can be in different stages in the process of species formation or dissolution. In some cases hybridization and introgression can create enormous challenges in interpreting data on genetic distinctions between groups. Hybridization is far more common in the evolutionary history of many species than previously recognized. As a result, the precise taxonomic status of an organism may be highly debated. This is the current case with the Mexican gray wolf (Canis lupus baileyi) and the red wolf (Canis rufus), and this report assesses the taxonomic status for each.

Contents

• The National Academies of SCIENCES • ENGINEERING • MEDICINE
• COMMITTEE ON ASSESSING THE TAXONOMIC STATUS OF THE RED WOLF AND THE MEXICAN GRAY WOLF
• BOARD ON LIFE SCIENCES
• BOARD ON AGRICULTURE AND NATURAL RESOURCES
• Preface
• Acknowledgment of Reviewers
• Summary
  • GUIDING PRINCIPLES
  • USING GENETICS AND GENOMICS TO DISCERN TAXONOMY
  • THE TAXONOMIC STATUS OF THE MEXICAN GRAY WOLF
  • THE TAXONOMIC STATUS OF THE RED WOLF
• 1. Introduction
  • PURPOSE OF THE STUDY
  • WHAT IS A WOLF?
  • EVOLUTION AND TAXONOMY
  • THE KEY ISSUES IN RECOGNIZING SPECIES AND SUBSPECIES
  • ORGANIZATION OF THE REPORT
  • REFERENCES
• 2. Guiding Principles for Identifying Species and Subspecies
  • WHAT IS A “SPECIES”? WHAT IS A “SUBSPECIES”?
  • UNDERSTANDING “SPECIES” IN LIGHT OF HYBRIDIZATION
  • ESTABLISHING GUIDELINES FOR DETERMINING TAXONOMIC STATUS
  • A FRAMEWORK FOR ESTABLISHING TAXONOMIC DESIGNATIONS
  • REFERENCES
• 3. Using Genes and Genomes to Identify Species and Subspecies
  • INDIVIDUAL NUCLEAR GENES
  • MITOCHONDRIAL DNA
  • GENOMES
  • REFERENCES
• 4. Is the Mexican Gray Wolf a Valid Subspecies?
  • A BRIEF TAXONOMIC HISTORY OF THE MEXICAN GRAY WOLF
  • IS THERE EVIDENCE FOR DISTINCTIVENESS OF MEXICAN GRAY WOLF POPULATIONS FROM OTHER NORTH AMERICAN CANIS POPULATIONS?
  • IS THERE EVIDENCE FOR CONTINUITY BETWEEN THE HISTORICAL MEXICAN GRAY WOLF LINEAGE AND THE PRESENT MANAGED POPULATIONS?
  • SYNTHESIS OF FINDINGS
  • REFERENCES
• 5. Is the Red Wolf a Valid Taxonomic Species?
  • A BRIEF TAXONOMIC HISTORY OF THE RED WOLF
  • IS THERE EVIDENCE THAT THE HISTORICAL POPULATION OF RED WOLVES WAS A DISTINCT LINEAGE?
  • IS THERE EVIDENCE FOR DISTINCTIVENESS OF CONTEMPORARY RED WOLVES FROM GRAY WOLVES AND COYOTES?
  • IS THERE EVIDENCE FOR CONTINUITY BETWEEN THE HISTORICAL RED WOLF POPULATION AND THE PRESENT MANAGED POPULATIONS?
  • SYNTHESIS OF FINDINGS
  • REFERENCES
• Glossary
• Appendix A. Open Session Meeting Agendas
• Appendix B. List of Webinars and Solicited Expert Input
• Appendix C. Biographical Sketches of Committee Members and Staff

Suggested citation:

National Academies of Sciences, Engineering, and Medicine. 2019. Evaluating the Taxonomic Status of the Mexican Gray Wolf and the Red Wolf. Washington, DC: The National Academies Press. doi: https://doi.org/10.17226/25351.

Digital Object Identifier: https://doi.org/10.17226/25351

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