What are the major evolutionary feats shared by all 3 phyla

What are the major evolutionary feats shared by all 3 phyla( Platyhelminthes, Nematoda, and Annelida)? What are the implications of these evolutionary feats? What two additional evolutionary feats are exhibited by Nemotoda? And 2 feats by Annelida?

Solution

Answer:

The major evolutionary feats shared by Platyhelminthes, Nematoda and Annelida are:

1. Level of Organization- Organ system level of organization

The organisms possesses distinct organ systems which marks the evolution of organ systems in animals.

2. Symmetry - Bilateral

This is often a result of moving in one direction, thus having a “head” end.

3. Triploblastic

They share common body wall organization, consisting of 3 layers. Three germ layers are evidence of slowly adapting layers of developmental control during embryogenesis as cells specialized for greater efficiency.

Two additional evolutionary feats exhibited by Nematoda are:

1. Coelom- Pseudocoelomate

2. Digestive system -Complete

Two feats of Annelida are:

1. Segmentation - Presented

2. Circulatory system -Present