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Topic outline

 
  • Time: 5 hours
    Level: Advanced

 
 

Introduction

  • Introduction Resource
  • This unit is concerned with macroevolution – the patterns and processes of evolution above the species level.
 

1 Systematics and the reconstruction of phylogeny

  • 1.1 Introduction Resource
  • To the lay person, it might seem surprising that there is any problem with the recognition of higher taxa. The very existence of long-established vernacular names for inclusive groupings of species (e.g....
  • 1.2 Taxa and relationships Resource
  • Until the mid-20th century, inferences about evolutionary relationships between species were generally based upon as wide a range of evidence as could be mustered. Evolutionary systematics is the name...
  • 1.3 Relationships between species Resource
  • Using the idea of blood relationships in people as an analogy, can you think of two distinct types of relationship between species?
  • 1.4 Grades and clades Resource
  • If species are grouped together because they show a similar extent of accumulated anagenetic change with respect to their ancestors, then the taxa so formed constitute grades. In Figure 1, morphological...
  • 1.5 Clades and mammals Resource
  • Are the mammals a clade?
  • 1.6 Clades and reptiles Resource
  • Are the reptiles a proper clade?
  • 1.7 Homologies Resource
  • If homologies could be recognised as such, then the relationships between species could be inferred from their shared homologies. Unfortunately, however, homologies and analogies cannot always be unambiguously...
 

2 A first approach to systematics

 

References and Acknowledgements

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