Phylum - Chordata
•Characteristics - have a
notochord and a dorsal nerve
cord at some point in their life
•A dorsal nerve cord is a tube
of nervous tissue just above
•A notochord is a firm tissue
mass along the dorsal side.
•Subphylum Urochordata: includes
tunicates, colonial drifting salps, and
•Larvaceans are tadpole-like
planktonic organisms thought to
resemble the theorized ancestor of
includes 25 species of lancelet.
Small filter feeders resemble
vertebrates, except they lack
•Subphylum Vertebrata: A
notochord has developed
into a spinal cord protected
by vertebrae (spine) and a
head with a brain.
Eddie and the Hagfish
Lampreys & Paddlefish
Class Agnatha: jawless fish.
Species include lampreys and hagfish.
Represent the ancestor of bony fish / sharks.
Subphylum Vertebrata - Class: Agnatha
4. Why are lampreys and hagfish important fish in evolution?
5. What characteristics does phylum Chordata have?
6. What are the characteristics of subphylum vertebrata?
7. What animals are in class Agnatha?
8. What happened to the notochord in vertebrates?
5 - 8
includes sharks, rays and
•Sharks and rays share a
•Characteristics - jawed
fish, that lack a swim
bladder, and have
5 - 9
•Sharks have a sense
of smell that detects
•Sharks have a
“conveyor belt” of
multiple rows of
•The new teeth
swing into place
as old teeth wear
out and fall away.
5 - 10
Sharks and rays have lateral lines – that detect
water motion and vibrations.
Sharks and rays have organs called ampullae of
Lorenzini which you can see as visible pits near their
snouts used to detect the electrical current created
by muscles and nerves of other animals.
Class: Chondrichthyes Inside Natures Giants - The
Great White Shark Part 1
•Fewer, but more mature
•Most fertilize eggs
Males deposit sperm in
the female via a pair of
organs called claspers.
Females lay egg cases
that develop for up to six
•A few shark species are ovoviviparous – the eggs
hatch within the mother’s body.
They give birth to live young rather than egg
Lemon Shark Gives Birth
The Great White
Shark Part 2
•Shark size ranges from hand-sized to the
whale shark – the largest fish.
•Whale sharks can reach 14m/46 feet.
•Basking sharks can reach 10m/33 feet.
•Megamouth sharks can reach 6m/20 feet.
•All three are filter feeders that consume
Shark Cage Diving for Tourists
Shark Cage Diving
Sharks & Rays Review 1
1. What type of animals are in class chondrichthyes?
2. List three characteristics of sharks & rays.
3. What is the ampullae of lorenzini for?
4. What are lateral lines for?
5. What is special about shark teeth?
7. Which gender of sharks has claspers?
8. What are two ways sharks give birth?
9. What is the largest fish in the world?
10. List three things you found most interesting about
sharks or rays.
The Great White Shark Part 3
Many sharks are in danger of
going extinct due to human
Sharks are typically not
dangerous to humans – we
don’t taste good to them.
5 - 18
Sharks in Peril
Swims With Whiite Sharks
2. Shark Fin Soup
Sharks in Peril
3. Sport Fishing
Sharks in Peril
Shark Fishing TX
•Rays, skates and guitarfish
•Ray anatomy is suited to life on
sandy bottoms or midwater.
•Adapted to midwater are the
eagle ray and manta ray.
•Pectoral fins have become
“wings” that stretch forward
over the gills and are fused to
the sides of the head.
5 - 22
•No longer need a tail for
swimming, (the tail has
become a defensive whip in
•Rays literally fly through the
•The largest rays are mantas
with wingspans exceeding 8
meters (26 feet).
•Like the largest shark, the
mantas feed on plankton. The Secret World of
Sharks and Rays
Sharks & Rays Review - 2
1. What animals are in class chondrichthyes?
2. What are two differences b/w fish and sharks/rays?
3. What are lateral lines for?
5. Why do people cut the fins off sharks?
6. What is the tail of the ray used for?
7. What is the largest ray?
8. At what depth in the water do most rays live in?
9. What do the largest rays feed on?
10. What are three things reducing the shark
Quiz next time
Sharks in Peril
5 - 25
Title: Sharks in Peril
• Write an essay that includes the three topics listed below.
Your essay should be persuasive in protecting the world’s
sharks that are left. Typed, double space, Vocabulary
will be checked.
• Shark nets
• Shark fin soup
• Shark sport fishing
• Introduction paragraph (1)
• Paragraph per topic discussed (3)
• Conclusion paragraph (1)
• 5 paragraphs all together (typed)
HW: Essay – due in four days
•Characteristics: jawed fish with
•Most have scales.
•Most control buoyancy using
oxygen gas exchanged to and
from blood circulation to a
(This allows many species to
hover nearly motionless in
•Most bony fish reproduce externally.
•The female lays her eggs, the male immediately
•Produce a vast number of off-spring with only a few
expected to survive to maturity.
•Most open-ocean and schooling fish
have a lighter underside and dark
topside for concealment.
•Bony fish living in reefs and on the
bottom use survival strategies more
diverse and include
concealment and armor instead of
•For this reason, you see far more
diversity in color,
shape, and size among reef and
•Important in worldwide
sardines, and anchovies.
•pollack, haddock, whitings, etc…
•A sixth of the world’s fish
•Alaskan pollack, the haddock and
whitings are important fisheries.
•Historically, worldwide fisheries
have influenced politics and caused
•Important fish in California
Return of the
Schools of Fish
Do other animals do this?
- Next slide
1. What does “osteo” mean?
2. Swim Bladder
4. Lateral line
5. Open Ocean
6. What are most fish color shading that live in the open
7. What are two defenses reef fish use?
8. What are some concerns regarding salmon?
9. What are two important fish that people eat a lot?
10. List three interesting things about bony fish.
• Phylum Chordata
• Subphylum Vertebrata
• Class Osteichthyes – bony fish
• Class Chondrichthyes – cartilaginous
10 FC on Osteichthyes - Fish
Question on one side, answer on the other
No ridiculous answers
Top card is just a title card with your full name,
period, title and date