BDE 224: Invertebrate Diversity
Lecture One: Introduction
Definitions Eumetazoa: A clade which includes all major animal phyla except
sponges, and a few other groups of animals.
7 Main Characteristics ● Metabolism: The catabolic and anabolic processes in
of Living Taxa organisms. These are the breakdown and synthesis
processes.
● Responsiveness: Cephalization to interpret stimuli.
● Movement: Allow organisms to disperse.
● Growth: Organism's ability to increase body size.
● Differentiation: Cells able form different tissue types.
● Reproduction: Sexual and asexual.
● Respiration: Intake of oxygen, etc.
Eumetazoa Characteristics of eumetazoans include:
● True tissues organized into germ layers
● An embryo that goes through a gastrula stage.
The clade is usually held to contain at least Ctenophora, Cnidaria,
and Bilateria.
Structure of Eumetazoa:
● Cells
● Tissue
● Organs
● Organ system (animal)
Hierarchical System 1. Kingdom
2. Phylum
3. Class
4. Order
5. Family
6. Genus
7. Species
Recognizing Groups of Symmetry: Radial (typically diploblastic) or bilateral.
Animals
Body Cavity: GVC (find definition), acoelomate, pseudocoelomate,
coelomate.
Embryological Mode of Development: Protostomes (mouth
develops first) or deuterostomes (anus forms first).
Germ Layer: Diploblastic (two germ layers – ectoderm and
endoderm) or triploblastic (three germ layers – ectoderm, mesoderm
and endoderm).
,Protostomes vs Protostomes
Deuterostomes ● Mouth forms first
● Coelom formation (schizocoel)
● Spiral cleavage
● Polar lobe formation in some
● Mollusca, Annelida, Anthropoda
Deuterostomes
● Anus forms first
● Enterocoel
● Radial cleavage
● Absent polar lobe
● Echinodermata and Chordata
Diploblast vs
Triploblast
Image: https://qsstudy.com/biology/diploblastic-and-triploblastic-organization
Terms for Phylogenetic Note: Phylogenetic trees are hypothetical.
Trees
Clade: When groups share a recent ancestor they form groups
Apomorphy: A derived character
Synapomorphy: A SHARED derived character
Autapomorphy: A derived character present in one group
Plesiomorphy: A primitive character
Symplesiomorphy: A shared primitive character
Node: Point of branching
Monophyly: Single origin
Polyphyletic: Multiple origins
Cladogenesis: Formation of new clade
Homology: Characters that arise from shared ancestry
Ingroup: Group under study
Outgroup: Group that is sister to the ingroup and is used to polarize
the ingroup characters
Branch Length The branch length for phylogenetic trees relates to the distance
between species. There will generally be a distance scale provided.
2
, Image:
https://www.google.com/url?sa=i&url=https%3A%2F%2Fusers.ugent.be%2F~avier
str%2Fprinciples%2Fphylogeny.html&psig=AOvVaw1gabR56Nqoshyk141FHGF8&
ust=1616090715536000&source=images&cd=vfe&ved=0CAIQjRxqFwoTCLD07pv
1t-8CFQAAAAAdAAAAABAD
Variables and Values These are used to determine the relation between the values.
on Nodes
Bootstrapping: Random resampling of a given point
Posterior Probability: No. of times the node is retrieved in the
given no. of trees.
3
, Lecture Two: Tree Topology
Definitions Topology: The study of geometrical properties and spatial relations
unaffected by the continuous change of shape or size of figures.
Groups Ingroup: Group under study
Outgroup: Sister to ingroup
Image: https://en.wikipedia.org/wiki/Outgroup_(cladistics)
Monophyly Monophyletic groups come from a common ancestor and
non-monophyletic groups do not.
Use the term “non-monophyletic” when describing groups.
Image: https://www.mun.ca/biology/scarr/Taxon_types.htm
Deep vs Shallow
Species
Different Species Same Species
● Deeper evolutionary ● Shallow evolutionary
questions questions
● Large number of phyla ● Rapid gene changes
nuDNA mtDNA
4
Lecture One: Introduction
Definitions Eumetazoa: A clade which includes all major animal phyla except
sponges, and a few other groups of animals.
7 Main Characteristics ● Metabolism: The catabolic and anabolic processes in
of Living Taxa organisms. These are the breakdown and synthesis
processes.
● Responsiveness: Cephalization to interpret stimuli.
● Movement: Allow organisms to disperse.
● Growth: Organism's ability to increase body size.
● Differentiation: Cells able form different tissue types.
● Reproduction: Sexual and asexual.
● Respiration: Intake of oxygen, etc.
Eumetazoa Characteristics of eumetazoans include:
● True tissues organized into germ layers
● An embryo that goes through a gastrula stage.
The clade is usually held to contain at least Ctenophora, Cnidaria,
and Bilateria.
Structure of Eumetazoa:
● Cells
● Tissue
● Organs
● Organ system (animal)
Hierarchical System 1. Kingdom
2. Phylum
3. Class
4. Order
5. Family
6. Genus
7. Species
Recognizing Groups of Symmetry: Radial (typically diploblastic) or bilateral.
Animals
Body Cavity: GVC (find definition), acoelomate, pseudocoelomate,
coelomate.
Embryological Mode of Development: Protostomes (mouth
develops first) or deuterostomes (anus forms first).
Germ Layer: Diploblastic (two germ layers – ectoderm and
endoderm) or triploblastic (three germ layers – ectoderm, mesoderm
and endoderm).
,Protostomes vs Protostomes
Deuterostomes ● Mouth forms first
● Coelom formation (schizocoel)
● Spiral cleavage
● Polar lobe formation in some
● Mollusca, Annelida, Anthropoda
Deuterostomes
● Anus forms first
● Enterocoel
● Radial cleavage
● Absent polar lobe
● Echinodermata and Chordata
Diploblast vs
Triploblast
Image: https://qsstudy.com/biology/diploblastic-and-triploblastic-organization
Terms for Phylogenetic Note: Phylogenetic trees are hypothetical.
Trees
Clade: When groups share a recent ancestor they form groups
Apomorphy: A derived character
Synapomorphy: A SHARED derived character
Autapomorphy: A derived character present in one group
Plesiomorphy: A primitive character
Symplesiomorphy: A shared primitive character
Node: Point of branching
Monophyly: Single origin
Polyphyletic: Multiple origins
Cladogenesis: Formation of new clade
Homology: Characters that arise from shared ancestry
Ingroup: Group under study
Outgroup: Group that is sister to the ingroup and is used to polarize
the ingroup characters
Branch Length The branch length for phylogenetic trees relates to the distance
between species. There will generally be a distance scale provided.
2
, Image:
https://www.google.com/url?sa=i&url=https%3A%2F%2Fusers.ugent.be%2F~avier
str%2Fprinciples%2Fphylogeny.html&psig=AOvVaw1gabR56Nqoshyk141FHGF8&
ust=1616090715536000&source=images&cd=vfe&ved=0CAIQjRxqFwoTCLD07pv
1t-8CFQAAAAAdAAAAABAD
Variables and Values These are used to determine the relation between the values.
on Nodes
Bootstrapping: Random resampling of a given point
Posterior Probability: No. of times the node is retrieved in the
given no. of trees.
3
, Lecture Two: Tree Topology
Definitions Topology: The study of geometrical properties and spatial relations
unaffected by the continuous change of shape or size of figures.
Groups Ingroup: Group under study
Outgroup: Sister to ingroup
Image: https://en.wikipedia.org/wiki/Outgroup_(cladistics)
Monophyly Monophyletic groups come from a common ancestor and
non-monophyletic groups do not.
Use the term “non-monophyletic” when describing groups.
Image: https://www.mun.ca/biology/scarr/Taxon_types.htm
Deep vs Shallow
Species
Different Species Same Species
● Deeper evolutionary ● Shallow evolutionary
questions questions
● Large number of phyla ● Rapid gene changes
nuDNA mtDNA
4
