II Animal Diversity a Lophotrochozoans 1 Platyhelminthes a

II. Animal Diversity a. Lophotrochozoans 1. Platyhelminthes a. Diversity - Planarians (free-living)

II. Animal Diversity a. Lophotrochozoans 1. Platyhelminthes a. Diversity - Planarians - Tapeworms - parasitic

II. Animal Diversity a. Lophotrochozoans 1. Platyhelminthes a. Diversity - Planarians - Tapeworms - parasitic - Flukes – parasitic Complex life cycles

II. Animal Diversity a. Lophotrochozoans 1. Platyhelminthes b. body plan - bilateral - nerve net cephalized – nerve ring

II. Animal Diversity a. Lophotrochozoans 1. Platyhelminthes b. body plan - bilateral - nerve net cephalized – nerve ring - ‘acoelomate’ – deep tissues…

II. Animal Diversity a. Lophotrochozoans 1. Platyhelminthes b. body plan - bilateral - nerve net cephalized – nerve ring - ‘acoelomate’ – deep tissues… - pharynx and convoluted gut: convoluted gut serves to distribute nutrients to “deep” tissues…acts as a ‘vascular’ (distributive) system… so the gut is called a “gastrovascular” cavity.

II. Animal Diversity a. Lophotrochozoans 2. Lophophores - a diverse group of worm-like animals that have the same feeding structure – a “lophophore” - complete gut

II. Animal Diversity a. Lophotrochozoans 3. Spiralians – wormy or segmented a. Annelida – segmented worms

II. Animal Diversity a. Lophotrochozoans 3. Spiralians – wormy or segmented a. Annelida – segmented worms 1. Diversity - polychaetes - oligochaetes - leeches

II. Animal Diversity a. Lophotrochozoans 3. Spiralians – wormy or segmented a. Annelida – segmented worms 2. Body Plan - coelomate - segmentation – allows for specialization of body parts and refined locomotion

II. Animal Diversity a. Lophotrochozoans 3. Spiralians – wormy or segmented a. Annelida – segmented worms 2. Body Plan - coelomate - segmentation – allows for specialization of body parts and refined locomotion - neural ganglia, closed circulation, excretory system

II. Animal Diversity a. Lophotrochozoans 3. Spiralians – wormy or segmented b. Mollusca – reduced segmentation; shells 1. Diversity - chitons

II. Animal Diversity a. Lophotrochozoans 3. Spiralians – wormy or segmented b. Mollusca – reduced segmentation; shells 1. Diversity - chitons - snails

II. Animal Diversity a. Lophotrochozoans 3. Spiralians – wormy or segmented b. Mollusca – reduced segmentation; shells 1. Diversity - chitons - snails - bivalves

II. Animal Diversity a. Lophotrochozoans 3. Spiralians – wormy or segmented b. Mollusca – reduced segmentation; shells 1. Diversity - chitons - snails - bivalves - cephalopods

II. Animal Diversity a. Lophotrochozoans 3. Spiralians – wormy or segmented b. Mollusca – reduced segmentation; shells 2. Body Plan

II. Animal Diversity a. Lophotrochozoans 3. Spiralians – wormy or segmented b. Mollusca – reduced segmentation; shells 2. Body Plan - reduction of segmentation (fusion) - decephalization in sessile orgs

II. Animal Diversity Aside… Patterns 1. Digestion: - blind gut - complete gut, - sementation and specialized organs, - reduced segmentation

II. Animal Diversity Aside… Patterns 2. Cephalization: - nerve net – radial symmetry (no head) - bilateral symmetry - head - increased cephalization – senses forward - complex brain (cephalopods)

II. Animal Diversity b. Ecdysozoans - exoskeleton that must be shed for growth; either a thin flexible CUTICLE, or a more rigid exoskeleton with chitin.

II. Animal Diversity b. Ecdysozoans - Phylogeny

II. Animal Diversity b. Ecdysozoans - exoskeleton that must be shed for growth; either a thin flexible CUTICLE, or a more rigid exoskeleton with chitin. - This is also a very diverse assemblage of Phyla; we are only going to consider a few.

II. Animal Diversity b. Ecdysozoans 1. Nematoda - molt four times, resecreting their cuticle each time

II. Animal Diversity b. Ecdysozoans 1. Nematoda - molt four times, resecreting their cuticle each time - complete digestive tract

II. Animal Diversity b. Ecdysozoans 1. Nematoda - molt four times, resecreting their cuticle each time - complete digestive tract - some cephalization with anterior neural ganglion

II. Animal Diversity b. Ecdysozoans 1. Nematoda - molt four times, resecreting their cuticle each time - complete digestive tract - some cephalization with anterior neural ganglion - free living and parasitic

II. Animal Diversity b. Ecdysozoans 1. Nematoda - molt four times, resecreting their cuticle each time - complete digestive tract - some cephalization with anterior neural ganglion - free living and parasitic - human parasites: trichinosis, filariasis, elephantiasis, Ascariasis (two foot intestinal worms)

II. Animal Diversity b. Ecdysozoans 2. Onchyphora and Tardigrada: thin chitinous exoskeleton; flexible; unjointed legs

II. Animal Diversity b. Ecdysozoans 2. Onchyphora and Tardigrada: thin chitinous exoskeleton; flexible; unjointed legs