Deuterostomes
By Levi Clancy for Student Reader on
updated
- Cladistics
- Binomial Nomenclature
- Caenorhabditis elegans
- Coliform Bacteria
- Darwinian Evolution
- Deuterostomes
- Drosophila melanogaster
- Echinoderms
- Evolutionary Chronometer
- Evolutionary Constraints
- Evolutionary agents
- Phylogenetics
- Phylum Annelida
- Phylum Cnidaria
- Phylum Platyhelminthes and Nemertea
- Phylum Porifera
- Reconstructing Phylogenies
- Taxonomic Units
The ancestors of deuterstomes are the extinct yunnanozoans. They had a large mouth, 6 pairs of external gills, and a lightly cuticularized segmented posterior body section. Later in detuerostome evolution, gills became internal and connected to the exterior via slits in the body wall. These gill slists were lost in the echinoderms. Deuterostomate animals include:
Echinodermata
Hemichordata
Chordata
The two major clades of deuterostomes are as follows:
Echinoderms & Hemichordates, which have a 3-part coelom and bilaterally symmetrical ciliated larva.
The chordates had a nonfeeding, tadpole-like larva and unique dorsal supporting structure.