L15 Animal Diversity1

8/12/2019 L15 Animal Diversity1

1/23

Animal diversity - a brief overview


2/23

Biological Classification

Example: Short-beaked EchidnaKingdom Animalia

Phylum Chordata

Class Mammalia

Order Monotremata

Family Tachyglossidae

Genus Tachyglossus

Species aculeatus


3/23

Kingdoms of Life

Eubacteria

Plantae

Fungi

Archaeobacteria

Protista

Animalia

Prokaryotes

Eukaryotes

True bacteria

Primary producers

External digestion

Ancient bacteria

Single cell

Consumers Viruses


4/23

Kingdom Animalia

Multi-cellular

Division of labour between individual cells or

groups of cells

CellsTissuesOrgans

GametesZygoteEmbryonic development

Diploid

30 phyla


5/23

Australias Biodiversity: a mega-diverse region

8% of the worlds total species diversity

>800,000 species

25,000 vascular plants

250,000 fungi

5,400 vertebrates (Phylum Chordata)

3,600 fishes, most endemic

850 birds, 45% endemic

700 reptiles, 89% endemic

357 mammals, 84% endemic (incl. 159 marsupials)

174 amphibians, 93% endemic

~520,000 invertebrates (the other 99%)

225,000 insects, many endemic


6/23

Beetle Diversity


7/23

Hidden Diversity


8/23

Phylum Porifera: Sponges

About 5000 species,most marine and

colonial

Filter feed on fineparticulate matter

drawn in with

water in through

pores

Skeleton used as

bath sponges Small calcareous sponges, Heron Island


9/23

Phylum Porifera: Sponges

Poorly differentiated tissues; no organs

No circulatory system

No nervous system

No respiratory or excretory system: gas

exchange and waste excretion by diffusion

Very simple digestive system: no mouth or gut


10/23

Phylum Cnidaria: jellyfish, sea wasps,

hydrozoans, sea anemones, corals

9000 species;marine orfreshwater

Medusa - free-floating,(pelagic) andbell shaped (eg

jellyfish)

Polyp - attachedtubular form (eg.a sea anemone)

Medusa of

Class

Scyphozoa -

jellyfish

Class Anthozoa -sea anemone


11/23

Nematocysts are a

diagnostic featureStinging organelles for

defence and capture

of prey

People often experience

stings (eg blue

bottle).

Stings from sea wasp

(box jellyfish) are

dangerous and often

fatal

Phylum Cnidaria


12/23

Class Anthozoa:

Corals

Sessile polyps that oftenlive colonially.

Feed by everting tentacles,catch zooplankton on

nematocysts.

Food passes betweenindividual polyps to

provide for whole colonyHard corals - polyps

embedded in skeleton ofcalcium carbonate


13/23

Phylum Cnidaria

Radial symmetry


Primitive nervous system: nerve net

No respiratory system: gas exchange by

diffusion

Simple digestive systemone-way

gastrovascular cavity


14/23

Phylum Platyhelminthes:

flatworms, tapeworms

and flukes12,700 species

Class TurbellariaFlatworms (free-living)

Class MonogeneaEctoparasitic flukes

Class Trematoda

Endoparasitic flukes(eg. liver fluke of sheep)

Class Cestoda

Tapeworms

(eg. pork tapeworm, hydatid cysttapeworm)


15/23

Phylum Platyhelminthes

Bilateral symmetry; dorso-ventrally flattened

Many are parasitic

Many are hermaphroditic


No respiratory system: gas exchange by diffusion

Simple nervous system / simple eyes

Simple digestive systemone-way gastrovascular

cavity


16/23

Phylum Nemertinea:

proboscis worms

900 species

Mostly marine species:

rocky crevices, in sand,

under rocks, algal mats

Have a unique eversible

anterior proboscis used

for catching prey

Elongated, anteriorlypointed

Range from few mm to ~30

metres in length

Many brightly coloured


17/23

Phylum Nemertinea

Bilateral symmetry; dorso-ventrally flattened

Limited closed circulatory system

Simple nervous system / simple eyes

No respiratory system

Through digestive systemmouth and anus

Primitive nitrogenous excretory system

Sexes separate


18/23

Phylum Nematoda: Roundworms

12,000 species, many

parasitic

Pseudocoelomate:possess fluid filledbody cavity

Found in virtually everyhabitat

Cylindrical, with tapered

ends

Thick collagen cuticle

Move by longitudinal

muscle contraction

Elephantiasis is caused by a

roundworm which blocks lymphatic

tissue, causing grotesque swelling in

affected regions


19/23

Phylum Nematoda: Roundworms

Bilateral symmetry; cylindrical

Pseudocoelomatepossess body cavity

Limited closed circulatory system

Rudimentary nervous system: aggregation of

nerve cells (brain), nerves running posteriorly,

nerve cells on cuticle (setae, papillae, amphids)

No respiratory system

Through digestive system


20/23

Phylum Annelida: Segmented worms

8700 species

Class Polychaeta (Marine bristle-worms)

Class Euclitellata

Sub-class Oligochaeta (Earthworms)

Sub-class Hirudinae (Leeches)

Earthworm


21/23

Phylum Annelida: Segmented worms

Coelomatepossess true body cavity

Segmentation and metamerism

Closed circulatory system (blood vessels)

Primitive respiratory systems

Nervous systembrain, ventral nervous cord

and ganglia in each segment

Through digestive system

Excretion through nephridial tubules


22/23

Phylum Annelida: Class Polychaeta

Marine bristle worms

Many setae per segment

Sedentary forms (tube-dwellers): filter organic

particles with tentaclesFree moving forms (surface,

pelagic, burrowers)

Pharynx can be evertedthrough mouth to catchprey

Rudimentary respiratory

system: gills on parapodia


23/23

Phylum Annelida: Class Euclitellata

Possess clitellumsecretes cocoon

for eggsLack parapodia

Sub-Class Oligochaeta (earthworms)

Few setae per segment Most are burrowing animals, feed on

vegetation or organic matter in soil,a few are carnivorous

Hermaphroditic

Sub-Class Hirudinae (leeches)

External parasites feeding on blood A giant AustralianEarthworm Digaster

L15 Animal Diversity1

Documents

Transcript of L15 Animal Diversity1