From Invertebrates Vertebrates. Phylum Chordata Most of the Chordates are vertebrates in the...

From Invertebrates Vertebrates

Phylum Chordata

• Most of the Chordates are vertebrates in the Subphylum: VERTEBRATA

• A few are “Invertebrate Chordates”

Phylum Chordata… at some point during their life cycle, the

organisms have:1. NOTOCHORD: Long firm rod – that

becomes the backbone.2. HOLLOW DORSAL NERVE CORD:

Above the notochord – this becomes the brain and spinal cord.

3. GILL SLITS: (pharyngeal slits): Often disappear.

MOST also have ...

A. Tail at some stage (post anal tail)

B. Two sets of “paired” appendages (arms & legs for example)

C. Closed Circulatory System (ventral heart)

D. Gills or Lungs for breathing

Before we get to “Chordata”

• There are a few groups of organisms that are “in-between”

• They are NOT true Invertebrates

• They are NOT Vertebrates – (as we are most familiar with) ...

Phylum Chordata• They are the “Invertebrate Chordates” *• Importance because they have a

common ancestor• SUBPHYLUM:

– Cephalochordata – Lancelets *– Urochordata – Tunicates *– Vertebrata – You

Cephalochordata

Cephalochordata - Lancelets

1. Scale-less, fishlike marine animal

2. Live in the bottom of the sea

3. Filter-feeders

Amphioxis

Urochordata – Tunicates (“Sea Squirts”)

• A tunicate is built like a barrel / filter feeders

• The name, "tunicate" comes from the firm, but flexible body covering, called a tunic.

• Spend most of adult lives attached to docks, rocks, or the undersides of boats (sessile)

Evolutionary clue …

• One clue that tunicates are related to vertebrates is found in the tunicate larva, or tadpole.

• It looks like a tiny tadpole, and has a nerve cord down its back.

• Similar to the nerve cord found inside of all vertebrates.

• … mature quickly, usually in just a few hours.

• The tadpoles do not feed at this stage, they do not have a mouth

• Their sole job is to find a place to live.

• When ready to settle, a sticky secretion helps them attach head first to the spot they have chosen.

• They then reabsorb the tail to build new structures needed for their adult way of life.

Tunicate Tadpoles …

Subphylum: Vertebrata

General Characteristics

• Usually 2 sets of paired appendages

• Closed Circulatory System

• Ventral Heart

• Gills or Lungs for Breathing

• Notochord is replaced by a backbone (or vertebral column) which encloses and protect the nerve cord (spinal cord)

Subphylum: Vertebrata

#1 – The Fishes

#1 – The Fishes• Gills: Obtain oxygen from water get rid of

CO2

• Most have “single loop” blood circulation

• Have a backbone (some notochord)

• A two chambered heart

• Most have external fertilization

• Gill Covering = Operculum

The Fish = Fishes

• Modern Fish are divided into three classes:– Class: Agnatha (jawless fish)

• Lampreys and Hagfish

– Class: Chondrichthyes (cartilaginous fish)

• Sharks, skates, rays

– Class: Osteichthyes = (bony fish)

• Lungfish, Trout, Bass, Salmon, Perch

Hagfish

• http://dsc.discovery.com/videos/nasty-by-nature-hag-fish-slime.html– Video showing the slime of hagfish

Class: Agnatha – Jawless Fish

• Characteristics– Primitive / No jaws – Cartilaginous skeleton – Scale-less skin – Oral sucker in place of

jaws – Predators and filter

feeders – Anti-coagulating saliva – fresh and salt water

• Lake Trout with wounds from Lamprey

A final note on Lampreys

Can you eat them?

Eat Lamprey?

• For centuries, river lampreys have been considered a delicacy in Europe

• King Henry I of England, in a fit of royal gluttony, is said to have died from a "surfeit of lamprey."

• The unappetizing appearance of the eel-like fish has so far not made this a big seller in this country.

• FYI: Lamprey goes for = $25 / pound

NEWS OF THE DAY

NEWS OF THE DAY

• https://www.youtube.com/watch?v=PQr-ghyLPzs

Class: ChondrichthyesSharks, Rays, Skates

• Characteristics:– Cartilaginous skeleton – Skin covered with

denticles, not scales – Five to seven gill slits

per side – No swim bladder – Internal fertilization – Spiral valve intestines

Spotted Eagle Ray

Skate

Scalloped Hammerhead

Scalloped Hammerhead Shark

• The strangely shaped head of this shark helps to allow some lift as it swims.

• The eyes are greatly separated which increases depth perception. Small pits on the underside of the head are sensitive to electrical fields and help to locate prey under the sand.

• They grow to about 12 feet.

Teeth – continually replace themselves.

Skate or Ray

• Skate:– Pelvic fin = 2 lobes– Tail Thick – no spine– 2 Dorsal fins on tail

(usually)– Thorn-like scales

called: “Bucklers”– Oviparous: “Mermaid

Purse”

• Ray:– Pelvic fin = 1 lobe– Tail slender – usually

with stinging spine– No dorsal fin (usually)– No bucklers– Usually larger than

skate– Viviparous: live

bearing

Class: Osteichthyes – Bony Fish

• Characteristics:– Skeleton made of bone – Lateral line – Two chambered heart / Ectothermic– Operculum (bony covering over the gills)– Swim bladder (adjusts buoyancy)– Paired fins

Characteristics Continued …

– Marine and fresh water species– Gills used for respiration – No external ears – No eye lids– External fertilization– Oviparous = lays eggs

Swim Bladder

AmphibiansClass: Amphibia

“Double Life”

Examples

• Frog / Toad – Salamander / Newt

• Mudpuppy / Hellbender

• Caecilian

Traits of Amphibians

• Their skin is smooth and slimy, often porous, moist skin with many glands (toads have several poison glands)

• Amphibians are cold-blooded / ectothermic

• Often have complex life cycle: egg, tadpole, adult (metamorphosis)

• Some species fertilize eggs externally, some internally.

Traits continued

• Usually have gills as larvae, and lungs as adults.

• Double loop circulation:– Heart:

• Larvae = 2 chambers• Adult = 3 chambers

– 2 Atria / 1 Ventricle (pumping section)– Most can breathe through the skin.

Single Loop Circulation Double Loop Circulation

Frog Vs Toad

• Smooth, soft, moist skin

• Large Tympanum (especially male)

• Slender Body• Long Legs / Speedy

swimmers• Clumps of eggs laid

in water

• Thick, dry skin, often bumpy

• Small tympanum• Plump body• Short legs / slow

moving• Strands of eggs laid

in water

Is a newt a salamander?

• Yes, but a salamander is not always a newt. Confused? The word "salamander" is the name for an entire group, or scientific order, of amphibians that have tails as adults. This includes animals commonly known as newts and sirens. Most of the animals in the salamander order look like a cross between a lizard and a frog. They have moist, smooth skin like frogs and long tails like lizards. The term "newt" is sometimes used for salamanders that spend most of each year living on land. Other names salamanders go by include olm, axolotl, spring lizard, water dog, mud puppy, hellbender, triton, and Congo eel….

– Courtesy of San Diego Zoo

Questions…

1. What is cutaneous respiration?1. Breathe through the skin

2. What does “TETRAPOD” mean?1. 4 Legs

3. What does “CAUDATA” mean?1. Long Tail (Salamanders / Newts)

1. What does “GYMNIOPHONA” mean?1. Limbless (Caecilians)

2. What does “ANURA” or Salienta mean?

1. Tail-less (Frogs and Toads)

• http://video.nationalgeographic.com/video/weirdest-newt

No not this kind… ha, ha!

Mudpuppy Anatomy

Mudpuppy Eggs

Frog Dissection

Dissection Intro

1. Heart has 3 chambers– 1 ventricle– 2 atrium

2. Fat Bodies: Yellow, fat-like purpose to feed the frog during hibernation – larger in female – to help nourish eggs

3. Kidneys (flat & reddish-brown) – filter blood

4. Frogs have no ribs5. Nictitating membrane is attached at the

bottom of the eye6. Eustachian tubes lead to the tympanum7. Glottis leads to the lungs8. Gullet leads to the esophagus stomach9. Liver has 3 lobes10.Pylorus is a valve at the lower part of the

stomach – it holds the food in the stomach until it is digested enough to enter the small intestine.

11.Pancreas secretes digestive enzymes and adjust insulin levels (in humans)

12.Mesentery is a clear tissue that holds the organs in place.

13.Pericardium – clear covering over the heart

Amplexus

• 1. Place the preserved frog in a dissecting tray

Mouth Anatomy Open your frog's mouth very wide, cutting the angles of the

jaw if necessary.

Internal

#42

#43

#44

#45

#39

#40#40

#41

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#49

#50

Phylum = Chordata

Subphylum: Vertebrata Class: Reptilia

Examples

• Snakes

• Lizards (gecko, skink, chameleon)

• Turtles

• Tortoises

• Alligators

• Crocodiles

Reptilia = Four Orders

1. Testudines or Chelonia = Turtles

2. Rhynchocephalia = Tuatara (primitive lizard-like reptile) – only one species survives (in New Zealand)

3. Squamata = Lizards, Snakes & Worm Lizards (see pg. 305 Zoology book)

4. Crocodilia = Alligators & Crocodiles

Characteristics

1. Skin SCALED – has to be “shed” to grow

2. Ectothermic = Cold Blooded

3. Most have claws

4. Eggs laid on land = Amniotic Egg

5. Internal Fertilization

6. Heart = 3 Chambers (Crocodiles = 4)

Turtles Vs Tortoises

Plastron Vs Carapace

Amniotic Egg

Snakes

• Carnivores with a hinged jaw, most smell with the tongue – take molecules out of the air to the roof of the mouth called “Jacobsen’s Organ”

• Venom:– Hemotoxin = Affects the circulatory system –

destroys RBC’s (red blood cells)– Neurotoxin – Shuts down the nervous

system.

Parthenogenesis

• The production of offspring without fertilization by a male

• It is rare in vertebrate species – Info …Most zoos keep only females, with

males being moved between zoos for mating– Why is this potentially not a good idea…?

Autotomy

• “Tail Loss” (self amputation) to escape predators

• Tail, Leg – etc.– Common among lizards

Snakes

• Identifying a Crocodile

• Identifying an Alligator

The average alligator grows to about 14 feetCrocodiles can reach 19 feet or more

Komodo Dragon

•On the Indonesian islands of Komodo

•There are only an estimated 1,000 to 5,000 living today.

•Reaching lengths of up to 3 m or more

Phylum = Chordata

Class: Aves = Birds

Evolved from Reptiles

Jurassic Period – 150 million years ago

Birds - Examples

• Pigeon• Penguin• Canada Goose• Hummingbird• Great Blue Heron• Robin• Cardinal• Owl

Characteristics

1. They have feathers = modified scales

2. Bones are “Pneumatic” - nearly hollow = lighter weight – with reinforced struts

3. Specially designed beak & feet for their way of life

4. Four chambered heart

5. Warm Blooded or Endothermic

6. Internal Fertilization

7. Oviparous = Egg Laying

8. Two Legs / Two Wings

9. Uropygial gland = Preen Gland (oil gland) – for waterproofing feathers (all contained in the pygostyle)

10. Wishbone = furcula

Uropygial gland

11. PRECOCIAL = Young are active a soon as they hatch. They can walk, swim feed themselves. (Many eggs) Examples: Ducks, Geese, Killdeer

12. ALTRICIAL = “Few” eggs; Hatch quickly, need parental care. Examples: Robins, pigeons, woodpeckers, hawks.

13. “Anting” – some birds pick up ants in bill – and rub over feathers – some ants give off “Formic Acid” – toxic to mites.

Relationships

• Monogamous birds:– About 90 % of all birds are monogamous. – one male mating with one female and forming

a "pair bond." That bond may last for a single nesting, one or more breeding seasons:

• Robins, Tree Swallows, Mourning Doves

– Or for life• albatrosses, swans, geese, eagles, and some owls

and parrots

Polygamy

• Polygamy occurs in two forms in bird societies: – Polygyny: one male with several females

• Red-winged black birds, house wrens, meadowlarks

– Polyandry: one female with several males• Spotted Sandpiper and Wilson's Phalarope • This is quite rare

Navigation & Migration

• Navigation: (how do birds navigate?)– Birds can use the sun, the stars, the earth's magnetic

field, & odors to find their way home. – Once they're very close to home they probably also

notice local landmarks and geography.

• Migration: (why do they migrate?)– Because during winter food, water, a sheltered place

to nest are difficult to find.– Food and water supply disappear (or freeze), plant

cover can vanish, and competition with other animals can increase.

Feathers

Phylum: ChordataSubphylum: Vertebrata

Class: Mammalia = The Mammals

Examples

• Skunk• Kangaroo• Human• Mouse• Bat• Dog• Squirrel• Dolphin

Characteristics

1. Mammals are warm blooded or endothermic

2. MOST are VIVIPAROUS = live birth

3. Female has mammary glands which produce milk to feed the young

4. Several kinds of teeth = “Heterodont” (bite, chew, grind)

Mammal Teeth

Rodent Teeth

5. Diaphragm – separates the chest cavity from the abdomen.

6. Four chambered heart

7. Skin: Most have sweat glands “sudoriferous glands” (not all have enough to cool themselves – human do)

8. Most have hair or “Pelage” – or a furry coat (protection, insulation, etc.)

Three Orders: Classified by how they reproduce

• MONOTREMES = Egg Laying Mammals– Oviparous = lays eggs – but obtains milk from

mother (not true nipples)• Examples:

– Duck-billed Platypus– Spiny Anteater / Echidna – lives over 50 years

• Monotremes – have cloaca that the intestine, urinary bladder all empty into.

– https://www.youtube.com/watch?v=yHjdIXN9v2g

Marsupials = Pouched Mammals

• Pouch is called “marsupium”– Examples:

• Kangaroo: https://www.youtube.com/watch?v=UpsnREY-6no • Koala• Wallaby• Wombat• Opossum

– Females re-mates on the day of giving birth or very soon after

– If newborn in pouch survive, newly conceived fetus goes into a “suspended” state = “embryonic diapause”

Placental Mammalshave a placenta

• Examples:– Shrews– Bats– Sloth– Rats– Rabbits– Wolves– Whales

– Dolphins– Manatee– Hippo– Zebra– Elephant– Gorilla– Human

Placental Mammals

• The embryo is fed via the umbilical cord and attachment to the mother’s uterus.

• The allantois and the yolk sac become the umbilical cord removing waste and feeding the embryo (fetus). Together with part of the chorion – they make up the placenta.

Amphibian eggs – Reptile eggs – Placental Mammal

Mammal Dentition

Mammalian Teeth

• Molars / Premolars: Grinding

• Canines: Tearing / Ripping

• Incisors: Cutting

• “Heterodont” = teeth specialized for different functions

Animal Relationships

Animal Relationships

• Intraspecific interactions are interactions among organisms of the same species

• Interspecific interactions are interactions among organisms of different species

• Symbiosis – Any relationship that involves two (or more)

species living together and interacting = predation, parasitism, commensalism, mutualism, etc.,

• but usually means mutualism

Symbiosis• Predation: When a larger animal eats

other, smaller animals. Lions may eat antelope, and wolves may eat deer. – Predator = Hunter (the one doing the hunting)– Prey = Hunted (the one captured!)

• Mutualism: A relationship between two species where both benefit.

Predator Vs Prey

Hunter or Hunted

Predator Vs Prey

Commensalism

• A relationship between two species that is beneficial to one but the other one is not helped nor harmed.– Often a “tough call” between Mutualism or

Commensalism…

Parasite• When a smaller organism feeds on a

larger, weakening or killing it.• This is a relationship where one organism

benefits and the other is harmed. • Often the host is not killed outright.

Because a parasite lives in/on the body of its host and needs the host to remain alive, it is usually advantageous for the parasite to not kill its host.

Parasites (ticks)

Parasites

Fungus on Insects

Coevolution

• Coevolution is the mutual evolutionary influence between two species (the evolution of two species totally dependent on each other).

• Each of the species has a major influence of the survival of the other, so they evolve together.

• Coevolution is an extreme example of mutualism

Coevolution

• Yucca moths & yucca plants – Yucca flowers are a

certain shape so only that tiny moth can pollinate them.

– The moths lay their eggs in the yucca flowers and the larvae (caterpillars) live in the developing ovary and eat yucca seeds.

Coevolution examples

• Acacia ants & acacia trees – Acacias are small, Central

American trees.– They have large, hollow

thorns. – The acacia ants live in the

thorns. – The plant makes a substance

used by the ants as food. – The ants defend the tree by

stinging any animal that comes near the plant.

– The ants also prune off seedlings of any other plants that sprout under “their” tree

Coevolution

• Coevolution is often seen in a number of species of flowering plants that coevolved with specific pollinators (insects, bats, etc). The pollinator gets a reward such as nectar.

• The common snapdragons that many people plant in their gardens are just the right shape & size for a bumblebee to pollinate & open up!

The EndYou did it!

Congratulations!