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Invertebrates 2 More Fun facts about: •  Protostomes

–  Lophotrochozoa –  Ecdysozoa

•  Nematodes (briefly) •  Arthropods

– Crustaceans – Chelicerates –  Insects

•  Deuterostomes •  Echinoderms •  Chordates (tomorrow)

July 2, 2019

Animals Porifera Metazoa

ANCESTRAL PROTIST

Ctenophora Eumetazoa

Deuterostom

ia

Bilateria

Lophotrochozoa Ecdysozoa

Cnidaria

Acoela

Hemichordata

Echinodermata

Chordata

Platyhelminthes

Syndermata

Ectoprocta

Brachiopoda

Mollusca

Annelida

Nematoda

Arthropoda

Sponges

Cnidarians

Echinoderms

Chordates

Brachiopods

Annelids

Molluscs

Arthropods

Ediacaran Cambrian PROTEROZOIC PALEOZOIC

Time (millions of years ago) 635 605 575 545 515 485 0

We will concentrate on these seven phyla

Where are humans in this

tree?

For each major group, think about:

• A familiar example • What is the general body plan?

–  i.e. Does it have a Head? Muscles? Bilateral symmetry?

• How does it eat? • How does it move? • How does it reproduce?

Figure 33.UN04

Porifera Cnidaria Lophotrochozoa Ecdysozoa Deuterostomia

The Ecdysozoa

Why do ecdysozoans molt?

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Phylum Nematoda C. elegans in the lab

https://www.youtube.com/watch?v=zjqLwPgLnV0

Phylum Arthropoda

CRUSTACEANS

Jointed appendages can have many shapes and functions

Figure 23.30 Two Segmented Body Plans (Part 1)

Crustacea Chelicera

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Figure 33.33

Heart Brain

Eyes

Poison gland

Pedipalp Chelicera

Book lung

Sperm receptacle

Gonopore (exit for eggs)

Silk gland

Spinnerets

Anus

Ovary

The Insects

By far the most species-rich group of animals!

Figure 33.35

Abdomen Thorax Head

Heart Cerebral ganglion

Mouthparts Ventral Nerve cords

Ovary

Vagina

Anus

Archaeognatha (bristletails; 350 species)

Zygentoma (silverfish; 450 species)

Winged insects (many orders; six are shown below)

Complete metamorphosis Incomplete metamorphosis Hemiptera (85,000 species)

Coleoptera (beetles; 350,000 species)

Diptera (151,000 species) Orthoptera

(13,000 species)

Hymenoptera (125,000 species)

Lepidoptera (120,000 species)

Proboscis

Insect life cycles

Insect mouthparts

Chewing Piercing

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Insects are the only invertebates that fly

Figure 33.UN05

Porifera Cnidaria Lophotrochozoa Ecdysozoa Deuterostomia

Phylum Echinodermata: Sea star (top left), brittle star (top right), sea urchin (bottom left), sea cucmber (bottom right), Echinoderm larvae are bilaterally

symmetrical

Echinoderms Echinoderms Short digestive tract

Stomach Anus

Spine Gills

Radial nerve

Gonads

Tube feet Water Skeleton

Ring canal

Digestive glands

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Figure 33.UN06a Figure 33.UN06b

Echinoderm Diversity