Are Animals eukaryotic or prokaryotic?

Unicellular or multicellular?

1.spiral determinant cleavage(plane of cell devision is diagonal to embryonic axis)

2. determinant- developmental fate determined early

3. coelum forms from blocks of mesoderm that are adjacent to blastopore, mouth develops from blastopore

1. radial indeterminant( plane of cell devision is parrallel or perpendicular to embryonic axis)

2. indeterminant- cell retains ability to develop into a complete embryo

3. coelum forms from mesoderm that buds from archentron mouth develops second, anus develops first from blastopore

like a spindle

fat at the center and tapered towards the ends

1. nutrients

2. gases

3. wastes

Hydrostatic

Exoskeletons

Endoskeletons

Skeletal system in which the skeleton is a hard outer encasement on the surface of the animal that is secreted by the epidermis and is made of calcium carbonate.

in arthropods can be a cuticle made out of chitin.

1. use of appendages to push water

2.use of tubes to force water

3.use of fins

4. undulation of tails

Describe Flying as a type of Land locomotion?

What adaptation have been made in these animals?

Gravity is a major challenge

Adaptations: Wings shaped like airfoil, small size, air-filled spaces in bones, loss of teeth(birds), loss of urinary bladder(birds)

1. New predator prey relationships generated diversity through the nervous system

2.Rise in atmospheric oxygen provide opportunities for animals with high metabolic rates and larger bodies to thrive

3.HOX gene complexes evolved providing developmental flexibility

They have no-backbone

make up 95% of animals

All phylum level clade include invertabrates

What clade did all sponges formerly belong to?

What clades do they belong to now?

Porifera(paraphyletic)

Silicea and calcarea

They are sedentary

most are marine

have no tissues

are asymmetrical

What is the mode of nutrition for the sponges?

How is this accomplished?

Suspension feeders.

Water is drawn through pores into a canal system, then cavity called the spongocoel. Water then flows out trough the osculum

How many cell layer do sponges have? 

What are the name(s) of the cell layer(s)?

2

the epidermis and the choanocytes

Digests food passed from choanocytes, and passes nutrients to other cells.

Makes fibers, spicules of mesohyl

can differentiate into any other sponge cell

1. choanocytes, amoebocytes produce gametes by meosis

2. sperm leaves in water flow, end up on plankton

3. egg remaining in canal system, gets fertilized by sperm drawn into sponge

4. zygote develops into larva, disperses in plankton

Describe the processes of Asexual reproduction in sponges.

2 processes

Fragmentation: waves tear sponges and since amoebocytes can differentiate into any cell type then the fragment can colonize any acceptable habitat

Gemmules: Sponges that live in freshwater ponds and intertidal zones are subject to drying up. gemmules are packets of choanocytes and amoebocytes(and spicules) in a dessication- resistant coat. when conditions are back in the gemmules favor the sponge will begin to colonize again

1.Have true tissues

2. radial symmetry

3. Endoder gives rise to the gastrodermis

4. Ectoderm gives rise to the epidermis

5. have a gelatinous mesoglea

1. cylindrical shape

2. sessile with exceptions

3. mouth "up"

4. feeding tentacles around mouth

5. have a mouth that is ring shaped

What are the characteristics of the medusa form of cnidarians?

(5 Characters)

1.bell-shaped

2. motile: drift or contract

3. mouth "down"

4. tentacles ring margin of bell

5. can be propelled by forcing water out of bell

1. Gastrovascular cavity acts as hydrostatic skeleton

2. Contractile fibers(composed of microfilaments) in epidermis, gastrodermis, and tentacles

3. Network of nerons( diffuse, no brain)

4.contraction of fibers can cause change in shape.

5. most have alternation of stages

What are the characteristics of the Platyhelminthes?

(8 Characters)

1. flatworms: dorsoventrally flattened

2. free living aquatic or terrestrial, or endoparasitic

3. microscopic to 20 meter long

4. Triploblastic, acoelomate

5. most have branched gastrovascular cavity with one opening(incomplete digestive tract).

6. no circulatory system

7. gas exchange, excretion across body surface

8. protonephridia sytem maintains solute balance

What type of clade is Turbellaria?

What clade does it belong to?

A class level clade

belongs to Phylum level clade Platyhelminthes

What are the characteristics of Organisms in the clade Turbellaria?

(4 Characters)

1. most are free-living marine: planarians are freshwater

2. body not devided

3.skeletal muscles below epidermis allows undulations

4. cilia on ventral surface help in crawling.

What are the characteristics of organisms in the clade Cestoda?

(6 Characters)

1. endoparasites of invertabrate intestines.

2. Have a scolex with hooks and suckers for attatchment.

3.no mouth or gastrovascular cavity

4. nutrients are absorbed across body wall

5. have a devided body

6. Proglottids contain mainly reproductive organs: shed from posterior end

What type of clade is Trematoda?

What clade does it belong to?

A class level clade

Phylum level clade Platyhelminthes

What are the characteristics of organisms in the clade trematoda?

(7 characters)

1. Are endoparasites

2. Have suckers

3. undevided bodies filled mainl with reproductive organs

4. wide range of hosts

5. complex life cycles- sexual and asexual stages, multiple hosts

6. Sexual reproduction in definitive host

7. Asexual reproduction in one or more intermediate hosts

Class level clade

belongs to Phylum Level Clade Platyhelminthes

What are the key morphological characteristics of organisms under the clade Mollusca?

 (7 Characters)

1. Soft bodied

2. Most have hard shell

3. Most are aquatic, some intertidal, and one group in moist terrestrial

4. Diverse modes of nutrition(herbivores, Carnivores, Detritovores, Suspension Feeders)

7.Most are dioecious

What is the body plan of organisms in the clade Mollusca?

12 features

1.foot which is a muscular organ used for locomotion

2.nerve cords extend from nerve ring encircling the esophagus into the foot

3.a viceral mass 

4.have a true ceolum

5.have a complete digestive tract

6.Have a nephridium 

7.Have open circulatory system

8.have a mantle 

 9.Have a mantle cavity

10.Have a visceral mass

11.Have Gills 

12. Have a radula 

1.secretes shell

2. Forms mantle cavity

3. encloses visceral mass

The gills are contained in the mantle cavity

the mantle cavity recieves digestive wastes and excretory products that are then washed out

Class level Clade

Belong to the Phylum level clade Mollusca

What are the Key morphological feature of organisms in the clade Polyplacophora?

(7 characters)

1.Live in marine or intertidal habitats

3. No head

4. Dorsal shell made of 8 plates

5. Broad flat foot for crawling, gliding

6. Abrading radula:scrape algae

7. Are herbivores

Class Level Clade

Belong to the Phylum Level Clade Mollusca

What are the Key morphological characteristics of Organisms in the Clade Gastropoda?

(6 characters)

1. Most marine some terrestrial

2. Shell in one piece and often coiled

3. Aquatic species have gills

4.In terrestrial have vascularized parts of mantle to function in gas exchange

5. Undergo torsion in embryonic development

6. Have a head

Class level clade

belongs to Phylum level clade Mollusca

Herbivores: The radula is ribbon like with teeth

Predators: drills that bore through shells of prey

Cone snails- eject venomous radular teeth

What are the Key morphological Characteristics of organisms in the clade Bivalvia?

(3 Characters)

1.Shell has 2 hinged valves: adductor muscles close

2. no head, no radula

3. photosensitive eyes on some

1. water comes into inccurent siphon formed by mantle folds

2. Water moves across gills in mantle cavity

3. gills have cilia and mucus to trap food and gas exchange

4. food is moved to mouth by palps

5. filtered water exits the excurrent siphon

1. Sedentary

2. Burrowers

3. swimmers

Do not move

in areas of high energy waves they attatch to their substrate by protein threads

A class level clade

Belong to the phylum level clade Mollusca

What are the key morphological characteristics of organisms in the clade cephalopoda?

(7 Characters)

 1. Active predators

2. enlarged head

3. Mantle that covers visceral mass

4.Foot joined with head

5.Tentacles with suction disks

6. closed circulatory system

7. most have lost their shell

propolsion

Water is drawn into the mantle cavity, then forced out through excurrent siphon

What are the key morphological characteristics of organisms in the clade Annelida?

(5 Characters)

1. Marine, freshwater, damp terrestrial habitats

2. Nutritional modes: Carnivores, suspension feeders, detritivores, and ectoparasites

3.Coelum partitioned by septa into somites or segments

4.Eucoelomate

5. Exhibit metamerism

A Class Level Clade

 Belongs to Phylum Level Clade Annelida

1.Cuticle of chitin

2. Chaete- integumentary bristle of chitin

 3.underneath epidermis have circular muscle then longitudinal

4. Have a coelum

5. Dorsal blood vessel that runs length

6. Pair of ganglia connected to ventral nerve cord

7. enlarged ganglia

8. complete digestive system

1. soil sucked in by the muscular pharynx and is transported to the crop via the esophagus

2.the crop then transports the soil to the gizzard which physically reduces the soil

3.The soil is then transported to the intestines for chemical digestion and absorption

To extract nutrients

through infoldings of the intestine

They are hermaphroditic and usually exchange sperm.

1.The clitellum usually produces a slime tube that earthworms move through

2. The slime tube picks up egg and sperm and forms a cocoon for the embryo

A class level clade

Belongs to the Phylum level clade Annelida

1. Internally similar to oligochaetes, except digestive tract not specialized to digest detritus

2. suspension feeder, carnivorous predators

3. Most marine, some freshwater, and some planktonic

4.Many chaete on a pair of paddle-like parapodia per segment

5. parapodia not jointed

6. some have appendages on head for sensing or prey capture

Class Level Clade

Belongs to Phylum Level Clade Annelida

1. mostly freshwater, some marine or terrestrial

2. predators or ectoparasites

3.ectoparasites have sucker that make incision in host with jaws or enzymatically digest hole

4. Secrete anesthetic and anticoagulant hirudin

5.Have pleats called annuli that allow expansion

6. Have enlarged side chambers of digestive tract to allow ingestion of large volumes of blood

What is the success of the diversity of arthropods attributed to?

( 3 succeses)

1.Fused body segment hard exoskeleton

2.specialized jointed appendages

3.change in sequence or regulation of existing HOX genes.

1.Eucoelomates

2. Cuticle that is flexible but not expandable and multilayered

1.Multilayered

2. Made of chitin in terrestrial species

3. Made of Calcium Carbonate in aquatic

4. Varies in thickness thinnest at joints thickest at points need protection

5. Anchoring surfaces for skeletal muscles

6. Provides support against gravity

7. molted to allow growth

8. newer cuticle produced beneath old

1. Consists of varying numbers of former segments

2. have specialized functions

3. Exoskeleton may or may not retain external evidence of segmentation

1.Walking

2.Swimming

3.Climbing

4.Defense

5.Food Aquisition

6.Feeding

7.Reproduction

8.Sensation

9.Well developed sensory organs

1. clawlike appendages; pincers or fangs

2. 2 tagmata

3.no antennae

1.Cephalothorax with 6 pairs of appendages that includes pedipalps for sensing,feeding, and reproduction. 4 pairs of walking legs

2. Abdomen with no appendages

Class level clade

Subphylem cheliceroforme

1.Ectoparasitic

2. have piercing and sucking mouth parts

3. usually less than 1mm 

4. ticks feed on the blood of invertabrates

5. mites attack vertabrates, invertabrates, and plants

6. belong to the clade arachnida

1. deliver venom

2. have a pumping stomach to pour digestive juices over prey

3. liquified prey tissue is sucked in

1. Subdue

2. Dropline

3. Egg cover

4. Gift Wrap

5. ballooning

ordinal level clade

Class level clade Arachnida

Subphylem level clade cheliceriforme

1.pincer like pedipalps

2. inject venom through peircing end of the abdomen

Class level clade

Subphylem level clade Cheliceriforme

What are the key characteristics of Horshoe Crabs?

(3 Characters)

1. Marine burrowers

2. Book gills on abdomen

3. Living fossils

What are the key characteristics of the Myriads?

(3 Characters)

1. Terrestrial

2. contains Centipedes and millipedes

3. Head appendages consist of 1 pair of sensory antennae 3 pair mouth parts including jaw like mandibles

What are the characteristics of the millipedes?

(4 Characters)

1. cylindrical body

2. numerous tagmata, each composed of 2 fused segments with 2 pairs of legs

3.herbivores

4. ancestors may have been early colonizers of land

1.dorsoventrally flattened body

2.carnivorous predators some with venom

3. segments with 1 pair of appendages

1. Contains insects and 6 legged wingless relatives

2.Thrive in all habitats except marine

3. 1st explosion with the evolution of flight

4. 2nd explosion with the evolution of angiosperms

5. 3 tagmata

6.mouth parts specialized for chewing, lapping, piercing, or sucking

7. have antennae

8. open circulatory system

9. cerebral ganglia in head

10.fused paired nerver cords and ganglia on ventral side

11.gas exchange- trachial tubules, or spiracles

1. are not appendages but extensions of the exoskeleton

2. 1 or 2 pairs

3. bees and wasps have 2 or more on each side hooked together and move as 1

4.Butterflys have 2 wings on each side that overlap and move as 1

5. Beetles and others have anterior wings that protect the wings underneath for flight

Nymphs resemble adults but smaller, have different body proportion, lack wings.

nymphs molt becoming more and more like the adult each time

1. most are marine or fresh water

2. 2 tagmata

3. typically highly specialized appendages on both tagmata

4. 2 pairs of atennae

5. gas exchage by gills or across integument

1. Cephalothorax

2. Abdomen

A class level clade

belongs to the Subphylem level clade Crustacea

Ordinal level clade

belongs to the class level clade malacostraca

1. mostly marine

2.shield shaped carapace

3.cuticle hardened by calcium carbonate

What are the key characteristics of the copepods and krill?

(3 characters)

1. are small

2. many are planktonic

3.very important food for other animals

1. are sessile

2. have a heavily calcified cuticle

3. often confused with molluscs

4. external appendages trap food from water

Radial indeterminate cleavage

mesoderm buds from archentron, forms coelum

blastopore forms anus

1. All marine with little tolerance to change in salinity

1. touch

2. changes in light and light intensity

3. temperature

4. orientation

5. the surrounding water

A class level clade

Belongs to the Phylem level clade Echinodermata

1. Star shaped, with central disk

2. crossed arms x shaped

3.mouth on underside

4. regenerate lost body parts

5. spines come from ossicles

6. gills are outpockets of coelum

7. complete digestive tract

1. water moves through madroporite in ring canal, into the ampula

2. muscles in the ampula contract, forcing water into the podium which lengthens

secrete adhesive compound and use deadhesive compounds to detatch and contract feet

allow them to crawl, capture prey, and hold their place

1. tube feet pule valves apart

2. they evert their stomach through their mouth 

3. secrete digestive enzymes onto prey

a class level clade

belongs to the Phylum level clade Echinodermata

What is the mode of nutrition of echinoideans?

What adaptations have they acqurired for this mode?

Herbivores

Chewing parts to gnaw on algae

What type of clade is Cnidoidea?

What clade does it belong to?

A class level clade

Belongs to the phylum level clade Echinodermata

What type of clade is Holothuroidea?

What clade does it belong under?

A class level clade

Belong to the phylum level clade Echinodermata

1. elongated

2. no spines

3. reduced embeded ossicles

4. 5 rows of tube feet

5. tube feet around mouth modified into feeding tentacles

6. Evisceration of digestive tract if attacked by prey that can be regenerated

1.notochord

2. dorsal hollow nerve chord

3. muscular post anal tail

4. Pharynx with slits or clefts

1.part of endoskeleton

2. in all chordata embryo

3. long flexible rod dorsal to digestive tract, ventral to chord

4.has fluid filled cells in fibrous sheath; hydrostatic skeleton

5. anchoring surface for trunk muscles 

6.Evolutionary precursor of vertebral column

7. in most vertebrates jointed skeleton develops around notochord

1. from ectoderm of embryo

2. forms a tube

3.Unique only to chordates

4. precursor of spinal cord and brain

What are the characteristics of the pharynx of chordates?

( 4 Characters)

1. pouches push outward to form grooves called clefts

2.clefts may form slit-like openings in body wall

3. soft and skeletal tissue between clefts are arches

4. In all chordate embryos

1. in non vertabrate chordates, function in suspension feeding

2. in jawed aquatic vertebrates, function for gas exchange; precursor gills in fish

3.In tetrapods, clefts do not form slits but develop into parts of ear and neck.

Contain skeletal elements and muscles that function for propulsion

is greatly reduced in many species

commonly know as branchiostoma(amphioxus)

1. live in marine environments

2. larvae in water column, adults in substrate

3.Larvae, adults have all 4 chordate characters

4. adults burrow, filter food through pharyngeal slits into atrium; food passed to digestive tract, water goes into atrium and out atriopore

5. Gas exchange mainly across body surface

6. Muscle segments allow undulations for swimming

1. Larvae live a few minutes but display all 4 chordate characteristics

2. larval pharynx non functional

3. Larva settle down and reabsorc notochord, and nerve chord, pharynx grows

4. adults become suspension feeders

5. often called sea squirts

What are the characteristics of the crainiates?

(9 Characters)

1. have a head

2. have a brain, skull, and sensory organs

3. derived characters- increased genetic complexity and neural crest

4. higher metabolism

5. more extensive muscles, including digestive tract

6. heart with two or more chambers

7. red blood cells with hemoglobin

8. kidneys

9. aquatic species gill slits associated with muscles and nerves allow pumping of water through pharynx for gas exchange and suction feeding

originated during the cambrian explosion

Haikouella- lancelet-like fossil with large brain, small eyes, fish-like muscle segments, gills- not yet a craniate

Myllokunmingia- true craniate fossil from cambrium had a cranium,ear and eyes capsules

What are the characteristics of hagfishes(Myxini)?

(5 Characters)

1. least derived extant craniate lineage

2. skull of cartilage; small brain,eyes, and ears

3. lack jaws and vertebral column(notochord is retained)

4. Live in Marine environments and are bottom dwelling scavengers

5. have slime glands- can produce several liters of slime in less than 1 minute, coating gills of attacking fish

What are the characteristics of the vertebrates?

(5 characters)

1. more complex nervous system

2. more extensive skull

3. vertebral column

aquatic vertebrates

4. dorsal,ventral, anal fins for propulsion and steering

5. more efficient gas exchange in gills

How is the nerve cord protected in vertebrates?

what does the vertebral column provide?

1. notochord with cartilaginous pipe with pairs of projections

2.surving forms highly derived

3. larvae live in streams and are suspension feeders similar to lancelets.

4. larvae also called ammocoete

5. adults migrate to lakes or seas and are ectoparasites on fish

6. adults have a suctorial mouth that is round with rasping tongue, ingests blood and fluids

7. lack of paired fins

What are the characteristics of conodonts?

(3 Characters)

1. usually 3-10 cm in length

2. Mineralized barbed hooks in mouth

3. no Jaw

What are the characteristics of the Ostracoderms?

(4 Characters)

1. arose during Ordovician through Devonian periods

2.Paired fins and inner ear

3. No jaws but mineralized bone covering parts of body

4.Bony shield composed of tooth-like structures that are thousands of small teeth fused together

What may have provided the selective pressure for the dental mineralization?

transition from filter feeding to preying may have provided selective pressure for dental mineralization

What are the characteristics of Gnathostome vertebrates?

(4 characters)

1. "Jaw Mouth": have moveable jaws

2.Major evolutionary step that allowed feeding on energy-rich living tissue

3.appeared in mid-Ordivician-470mya

4.Extant gnathostomes include sharks through mammals

What are the derived characters of Gnathostomes?

(3 characters)

1. Hinged jaws

2. enlarged forebrain allowed better smell and vision

3. Duplication of Hox genes and other genes allowed further complexity

What type of clade are chondricythes?

What clade does it belong to?

A class level clade

Subphylem Vertebrata

Phylum Chordata

What are the characteristics of the Chondricthyes?

(4 Characters)

1. includes sharks, rays, and ratfishes

2. skeleton primarily cartilage but somewhat calcified/mineralized

3. Traces of bone in scales,teeth, and some skeletal elements

4. evolved from more mineralized ancestors

What are the characteristics of sharks?

(2 characters)

1. Have pectoral and pelvic fins

2. Have several rows of teeth (are scales around jaw)

What are the characteristics of Rays?

(4 characters)

1. Dorso-ventrally flattened body

2. wing-like pectoral fins

3. Benthic(on the bottom of aquatic habitats)

4. Jaws that crush molluscs and crustaceans

What are the characteristics of Ratfishes?

(2 Characters)

1. Deep-Dwelling organisms

2. Long tapering caudal fin

What type of clade is Osteichythyes?

What clade does it belong to?

Class level clade

Subphylum vetebrata

Phylum Chordata

What are the characteristics of Bony fishes?

(4 Characters)

1. skeleton mostly bone with some cartilage

2. breathe by drawing water over gills derived from pharynx and Pharyngeal slits

3. covered with bony scales and mucous glands

4. have a swim bladder

From what did the swim bladder evolve in bony fish?

What was its original function?

What type of clade is Actinopterygii?

What clade does it belong under?

A subclass level clade

Class Osteichthyes

1. Fish supported by bony rays

2. Most extant fish

3. originated in fresh water

What type of clade is Sarcopterygii?

What clade does it belong under?

Sub class level clade

Class osteichthyes

1. Lobe finned fishes

2. Rod-shaped bones surrounded by muscle in fins

3. include lung fishes and coelcanths

4. Extict lobe-finned fishes were the ancestors of the tetrapods

What are the derived characters of the tetrapods?

(3 Characters)

1. limbs

2. specialized vertebra in neck that allowed head to be lifted for air breathing

3. bones of pelvic girdle articulated with vertebral column that helped to counter gravity

What type of clade is Amphibia?

What clade does it belong under?

Class level clade

Phylum Chordata

1. live in water and land

2. Many have aquatic larval stage that undergoes metamorphosis to become a terrestrial adult

3. eggs have no shell

4. mucous-producing glands

What type of clade is Urodela?

What clade does it belong under?

Ordinal level clade

Class Amphibia

What are the characteristics of organisms in the clade urodela?

(3 Characters)

1.Includes salamanders

2. Tailed

3. 4 well-developed legs for crawling

What type of clade is Anura?

What clade does it belong under?

Ordinal level clade

Class amphibia

1. includes frogs

2.tailess

3. Strongly developed hind limbs

4. Hop for locomotion

What type of clade is Apoda?

What clade does it belong under?

Ordinal level clade

Class Amphibia

1. includes caercillians

2. legless

3. are burrowing creatures

What are the characteristics of the amniotes?

(2 Characters)

1. Includes reptiles,birds and mammals

2. organisms produce and amniotic egg

What type of clade is Reptillia?

What clade does it belong under?

A class level clade

Phylum Chordata

1. extant clade include turtles, crocodilians, birds, squamates(lizards and snakes), tuataras

2. epidermal scales made of keratin

3. birds also have feathers

4. lay shelled eggs on land

What type of clade are turles?

What clade do they belong under?

Ordinal level clade

Class Reptilia

Phylum Chordata

What are the characteristics of Turtles?

(3 Characters)

1. Have a boxlike bony shell fused to vertebrae and ribs

2. no teeth

3. enlarged scales on shell

What type of clade is Crocodilia?

What clade does it belong under?

Ordinal level clade

Class Reptilia

Phylum Chordata

What are the characteristcs of organisms in the clade Crocodilia?

(5 Characters)

1. include alligators and crocodiles

2. semi-aquatic predator

3. elongate jaws

4. numerous cone shaped teeth

5. large epidermal scales

What type of clade are the birds?

What clade do they belong under?

Ordinal level clade

Class Reptilia

Phylum Chordata

1.no urinary bladder

2. usually only 1 ovary

3. gonads small except during breeding season

4. no teeth

5. have a beak

6. efficient 4 chambered heart and efficient gas exchange system

7. acute vision

1. Are attatched with large pectoral muscles attatched to keel on sternum

2. shaped as airfoils

3. bones show pneumatism(air spaces)

Have shafts, barbs, barbules and hooks

1.Have no hooks

2. are close to the body

3. retain body heat from metabolism

When did feather evolve?

What were they probably used for?

Long before flight

Probably used for social display or cryptic coloration

What type of clade is Squamata?

What clade does it belong under?

Ordinal level clade

Class Reptiilia

Phylum Chordata

What are the characteristics of Squamates?

(3 characters)

1. includes snakes and lizards

2. most lizards have legs, snakes are legless

3. Lizards have external ear openings. snakes do not

What type of clade is Mammalia?

What clade does it belong under?

A class level clade

Phylum Chordata

What are the derived characters of mammals?

(6 characters)

1. mammary glands that produce milk

2. hair for retention of heat(endothermy)

3. efficient circulation with a 4 chambered heart

4.efficient gas exchange with a diaphram

5. large brain with learning during parental care

6. heterodonty(differentiated teeth)

1. Monotremes

2.Marsupials

3. Eutherians

What are the characteristics of the monotremes?

(2 characters)

1.Include platypus and echidnas

2.Are egg laying

What are the characteristics of Marsupials?

(2 characters)

1. Include opossums, Kangaroo, and Koalas

2. Have a pounch in which offspring develop after birth

What are the characteristics of Eutherians?

(2 characters)

1. include all placental mammals

2. Are viviparous meaning offspring complete embryonic development in the uterus