ANIMAL DIVERSITYDIVERSITY
Where are We?
What makes an Animal? Eukaryotic Heterotrophic Multicellular Diploid Are motile at some stage of the Life Cycle
Evolutionary History in Development
Why is embryonic development important in our understanding of evolution? Evolutionary Developmental Biology (“Evo-Devo”) – Comparisons of developmental characters in different organisms can often reveal ancestral relationships – Excellent characters for use in building phylogenies Ernst Haeckel 1892
Development
Videos Development of the Blastula Gastrulation
Blastopore Mouth: protostomes Anus: deuterostomes
Triploblastic Development Protostomes (“mouth first”) Deutero stomes (“mouth second”) Blastopore= mouth Blastopore= anus
Body Plan: Symmetry
Symmetry Radial SymmetryBilateral Symmetry
Symmetry Practice
Tissues Parazoa - group of organisms without true tissues Eumetazoa - group of animals with true tissues
Germ Layers Diploblastic – Endoderm + ectoderm Triploblastic – Endoderm + mesoderm + ectoderm
Triploblastic Animals - Body Cavities
Red = ectoderm Yellow = endoderm Blue = mesoderm
Lophotrochozoa Trochophore larvae Lophophore Used for filter feeding
Ecdysozoa
Today’s Lab Work through all stations (use flowchart!) Identify unknowns in tank Show me your tree!
Flow Chart True Tissues? Parazoa Eumetazoa yes no Number of Germ Layers? two three Diploblastic Triploblastic Fate of blastopore? mouth anus Protostome Deuterostome Which clade? Lophotrochozoa Ecdysozoa Trochophore larvae or lochophore (or neither) ? Asymmetry Radial symmetry Bilateral symmetry Acoelomate, Pseudocoelem, or Coelem Coelom